2022/05/17 更新

写真a

ツネダ サトシ
常田 聡
所属
理工学術院 先進理工学部
職名
教授
プロフィール
常田研究室は1996年4月に早稲田大学理工学部応用化学科内に誕生しました。その後,2007年4月の理工学部再編に伴い,理工学と医学分野との融合を図るミッションを持って,先進理工学部生命医科学科/大学院先進理工学研究科生命医科学専攻に移ることになり,新しく生まれ変わりました。また,2008年4月には,東京女子医科大学の隣接地に新設された先端生命医科学センター(通称TWIns)に研究場所を移しました。私たちは,新しい融合研究を推進するため,東京女子医科大学,順天堂大学医学部,産業技術総合研究所など多くの研究機関と積極的に共同研究を推進しています。私たちは,細菌が単一または複合状態でどのような機能を果たすかについて分子生物学的手法を用いて詳細に解明し,それらの機能を引き出す応用技術の開発を進めています。研究テーマは,機能解析手法の開発から分子メカニズムの解明,そして応用技術の開発に至るまで幅広いレンジで設定し,医療・健康・食品・環境分野へ貢献することを常に念頭に置いた実学的研究を展開しています。

兼担

  • 理工学術院   大学院先進理工学研究科

  • 附属機関・学校   グローバルエデュケーションセンター

学内研究所等

  • 2020年
    -
    2022年

    理工学術院総合研究所   兼任研究員

学歴

  •  
    -
    1994年

    東京大学   工学系研究科   化学生命工学専攻  

  •  
    -
    1994年

    東京大学   工学系研究科   化学生命工学専攻  

  •  
    -
    1994年

    東京大学   工学系研究科   化学生命工学専攻  

  •  
    -
    1991年

    東京大学   工学系研究科   化学工学専攻  

  •  
    -
    1989年

    東京大学   工学部   化学工学  

学位

  • 東京大学   博士(工学)

  • The University of Tokyo   Doctor of Engineering

経歴

  • 2012年
    -
    2014年

    早稲田大学環境保全センター 所長(兼務)

  • 2012年
    -
    2014年

    早稲田大学環境保全センター 所長(兼務)

  • 2007年
    -
     

    早稲田大学 教授

  • 1999年
    -
    2007年

    早稲田大学 助教授

  • 1999年
    -
    2007年

    早稲田大学 助教授

  • 1996年
    -
    1999年

    早稲田大学 専任講師

  • 1995年
    -
    1996年

    理化学研究所 基礎科学特別研究員

  • 1995年
    -
    1996年

    理化学研究所 基礎科学特別研究員

▼全件表示

所属学協会

  •  
     
     

    American Society for Microbiology (ASM)

  •  
     
     

    International Society for Microbial Ecology (ISME)

  •  
     
     

    International Water Association (IWA)

  •  
     
     

    日本イオン交換学会

  •  
     
     

    日本バイオフィルム学会

  •  
     
     

    日本水処理生物学会

  •  
     
     

    腸内細菌学会

  •  
     
     

    日本細菌学会

  •  
     
     

    日本免疫学会

  •  
     
     

    日本生物工学会

  •  
     
     

    環境バイオテクノロジー学会

  •  
     
     

    日本水環境学会

  •  
     
     

    化学工学会

▼全件表示

 

研究分野

  • 細菌学

  • 応用微生物学

  • 環境負荷低減技術、保全修復技術

  • バイオ機能応用、バイオプロセス工学

研究キーワード

  • 生物工学、微生物生態学

論文

  • Methanol tolerance and acclimation in the anammox process using a gel carrier

    Kazuichi Isaka, Toshifumi Osaka, Yuya Kimura, Nanami Iwasaki, Satoshi Tsuneda

    Biochemical Engineering Journal   165  2021年01月

     概要を見る

    The methanol tolerance level of the anammox process was investigated in continuous feeding tests. In the conducted pulse methanol addition tests of gel carrier-immobilized anammox bacteria, the nitrogen removal performance was not significantly affected at influent methanol concentrations of up to 30 mg L−1; however, irreversible inhibition occurred at 40 mg L−1. In the absence of methanol acclimation, the anammox process showed low methanol tolerance levels. Moreover, the stepwise addition of 5 mg L−1 of methanol resulted in no anammox inhibition even when the methanol concentration became 100 mg L−1. The effluent total organic carbon concentration did not increase with the increase in the influent methanol concentration; this indicates that methanol was consumed along with the nitrate or nitrite by heterotrophic denitrification. These results show that the increase in the methanol tolerance level was due to the increase in the methanol consumption ability during the anammox process because of the increased denitrifying bacteria and not because the anammox bacteria exhibited resistance to methanol. The microbial community analysis revealed the dominant species in the gel carriers (Candidatus Jettenia asiatica), existence of methylotrophic bacteria, and growth in the methanol-consuming bacterial population.

    DOI

  • CREB3L1 overexpression as a potential diagnostic marker of Philadelphia chromosome‐negative myeloproliferative neoplasms

    Soji Morishita, Hajime Yasuda, Saya Yamawaki, Hideya Kawaji, Masayoshi Itoh, Yoko Edahiro, Misa Imai, Yasushi Kogo, Satoshi Tsuneda, Akimichi Ohsaka, Yoshihide Hayashizaki, Masafumi Ito, Marito Araki, Norio Komatsu

    Cancer Science    2020年12月

    DOI

  • Nitrogen and Oxygen Isotope Signatures of Nitrogen Compounds during Anammox in the Laboratory and a Wastewater Treatment Plant

    S. Kotajima, K. Koba, D. Ikeda, A. Terada, K. Isaka, K. Nishina, Y. Kimura, A. Makabe, M. Yano, H. Fujitani, N. Ushiki, S. Tsuneda, M. Yoh

    Microbes and Environments   35 ( 4 ) 20031  2020年12月  [査読有り]  [国内誌]

    DOI PubMed

  • Genomic and Physiological Characteristics of a Novel Nitrite-Oxidizing Nitrospira Strain Isolated from a Drinking Water Treatment Plant

    H. Fujitani, K. Momiuchi, K. Ishii, M. Nomachi, S. Kikuchi, N. Ushiki, Y. Sekiguchi, S. Tsuneda

    Frontiers in Microbiology   11 ( 545190 ) 1 - 13  2020年09月  [査読有り]

    DOI

  • Enrichment of Comammox and Nitrite-Oxidizing Nitrospira From Acidic Soils

    Y. Takahashi, H. Fujitani, Y. Hirono, K. Tago, Y. Wang, M. Hayatsu, S. Tsuneda

    Frontiers in Microbiology   11 ( 1737 ) 1 - 16  2020年07月  [査読有り]

    DOI

  • Physiological and Genomic Characterization of a New “Candidatus Nitrotoga” Isolate

    K. Ishii, H. Fujitani, Y. Sekiguchi, S. Tsuneda

    Environmental Microbiology   22 ( 6 ) 2365 - 2382  2020年06月  [査読有り]

    DOI

  • Transcriptome Analysis of the Ammonia-Oxidizing Bacterium Nitrosomonas mobilis Ms1 Reveals Division of Labor between Aggregates and Free-Living Cells

    R. Isshiki, H. Fujitani, S. Tsuneda

    Microbes and Environments   35 ( 2 ) 1 - 9  2020年06月  [査読有り]  [国内誌]

    DOI PubMed

  • MazF Endoribonucleolytic Toxin Conserved in Nitrospira Specifically Cleaves the AACU, AACG, and AAUU Motifs

    R. Aoi, T. Miyamoto, A. Yokota, Y. Ota, H. Fujitani, S. Tsuneda, N. Noda

    Toxins   12 ( 5 )  2020年04月  [査読有り]

    DOI

  • Successful Enrichment of Low-Abundant Comammox Nitrospira from Nitrifying Granules under Ammonia-Limited Conditions

    H. Fujitani, M. Nomachi, Y. Takahashi, Y. Hasebe, M. Eguchi, S. Tsuneda

    FEMS Microbiology Letters   367 ( fnaa025 ) 1 - 8  2020年03月  [査読有り]

    DOI

  • Quantification of native mRNA dynamics in living neurons using fluorescence correlation spectroscopy and reduction-triggered fluorescent probes

    Hirotaka Fujita, Ryota Oikawa, Mayu Hayakawa, Fumiaki Tomoike, Yasuaki Kimura, Hiroyuki Okuno, Yoshiki Hatashita, Carolina Fiallos Oliveros, Haruhiko Bito, Toshio Ohshima, Satoshi Tsuneda, Hiroshi Abe, Takafumi Inoue

    Journal of Biological Chemistry   in press  2020年  [査読有り]  [国際誌]

  • Conditional Hfq Association with Small Noncoding RNAs in Pseudomonas aeruginosa Revealed through Comparative UV Cross-Linking Immunoprecipitation Followed by High-Throughput Sequencing

    K. Chihara, T. Bischler, L. Barquist, V. A. Monzon, N. Noda, J. Vogel, S. Tsuneda

    mSystems   4 ( 6 ) e00590-19  2019年12月  [査読有り]

    DOI

  • Draft genome sequence of Acidovorax sp. strain NB1 isolated from a nitrite-oxidizing enrichment culture

    Hiroto Ide, Kento Ishii, Hirotsugu Fujitani, Satoshi Tsuneda

    Microbiology Resource Announcements   8 ( 33 ) e00547-19  2019年08月  [査読有り]

  • Fluorescent Nucleic Acid Probe in Droplets for Bacterial Sorting (FNAP-Sort) as a High-Throughput Screening Method for Environmental Bacteria with Various Growth Rates

    Y. Ota, K. Saito, T. Takagi, S. Matsukura, M. Morita, S. Tsuneda, N. Noda

    PLOS ONE   14 ( 4 ) e0214533 - e0214533  2019年04月  [査読有り]

    DOI

  • Nitrosomonas europaea MazF Specifically Recognises the UGG Motif and Promotes Selective RNA Degradation

    T. Miyamoto, A. Yokota, Y. Ota, M. Tsuruga, R. Aoi, S. Tsuneda, N. Noda

    Frontiers in Microbiology   9 ( 2386 ) 1 - 10  2018年10月  [査読有り]

    DOI

  • Low-temperature culturing improves survival rate of tissue-engineered cardiac cell sheets.

    Katsuhisa Sakaguchi, Yuto Hinata, Yuki Kagawa, Kiyotaka Iwasaki, Satoshi Tsuneda, Tatsuya Shimizu, Mitsuo Umezu

    Biochemistry and biophysics reports   14   89 - 97  2018年07月  [査読有り]  [国際誌]

     概要を見る

    Assembling three-dimensional (3D) tissues from single cells necessitates the use of various advanced technological methods because higher-density tissues require numerous complex capillary structures to supply sufficient oxygen and nutrients. Accordingly, creating healthy culture conditions to support 3D cardiac tissues requires an appropriate balance between the supplied nutrients and cell metabolism. The objective of this study was to develop a simple and efficient method for low-temperature cultivation (< 37 °C) that decreases cell metabolism for facilitating the buildup of 3D cardiac tissues. We created 3D cardiac tissues using cell sheet technology and analyzed the viability of the cardiac cells in low-temperature environments. To determine a method that would allow thicker 3D tissues to survive, we investigated the cardiac tissue viability under low-temperature culture processes at 20-33.5 °C and compared it with the viability under the standard culture process at 37 °C. Our results indicated that the standard culture process at 37 °C was unable to support higher-density myocardial tissue; however, low-temperature culture conditions maintained dense myocardial tissue and prevascularization. To investigate the efficiency of transplantation, layered cell sheets produced by the low-temperature culture process were also transplanted under the skin of nude rats. Cardiac tissue cultured at 30 °C developed denser prevascular networks than the tissue cultured at the standard temperature. Our novel findings indicate that the low-temperature process is effective for fabricating 3D tissues from high-functioning cells such as heart cells. This method should make major contributions to future clinical applications and to the field of organ engineering.

    DOI PubMed

  • Stochastic expression of lactate dehydrogenase A induces Escherichia coli persister formation

    Naoki Yamamoto, Rino Isshiki, Yuto Kawai, Daiki Tanaka, Tetsushi Sekiguchi, Shinya Matsumoto, Satoshi Tsuneda

    Journal of Bioscience and Bioengineering   126 ( 1 ) 30 - 37  2018年07月  [査読有り]

     概要を見る

    Bacterial persisters are phenotypic variants that survive the treatment of lethal doses of growth-targeting antibiotics without mutations. Although the mechanism underlying persister formation has been studied for decades, how the persister phenotype is switched on and protects itself from antibiotics has been elusive. In this study, we focused on the lactate dehydrogenase gene (ldhA) that was upregulated in an Escherichia coli persister-enriched population. A survival rate assay using an ldhA-overexpressing strain showed that ldhA expression induced persister formation. To identify ldhA-mediated persister formation at the single-cell level, time-lapse microscopy with a microfluidic device was used. Stochastic ldhA expression was found to induce dormancy and tolerance against high-dose ampicillin treatment (500 μg/ml). To better understand the underlying mechanism, we investigated the relationship between ldhA-mediated persister formation and previously reported persister formation through aerobic metabolism repression. As a result, ldhA expression enhanced the proton motive force (PMF) and ATP synthesis. These findings suggest that ldhA-mediated persister formation pathway is different from previously reported persister formation via repression of aerobic metabolism.

    DOI

  • Skewed megakaryopoiesis in human induced pluripotent stem cell-derived haematopoietic progenitor cells harbouring calreticulin mutations

    Hiraku Takei, Yoko Edahiro, Shuichi Mano, Nami Masubuchi, Yoshihisa Mizukami, Misa Imai, Soji Morishita, Kyohei Misawa, Tomonori Ochiai, Satoshi Tsuneda, Hiroshi Endo, Sou Nakamura, Koji Eto, Akimichi Ohsaka, Marito Araki, Norio Komatsu

    British Journal of Haematology   181 ( 6 ) 791 - 802  2018年06月  [査読有り]

     概要を見る

    Somatic mutations in the calreticulin (CALR) gene have been found in most patients with JAK2- and MPL-unmutated Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs). It has recently been shown that mutant CALR constitutively activates the thrombopoietin receptor MPL and, thus, plays a causal role in the development of MPNs. However, the roles of mutant CALR in human haematopoietic cell differentiation remain predominantly elusive. To examine the impact of the 5-base insertion mutant CALR gene (Ins5) on haematopoietic cell differentiation, we generated induced pluripotent stem cells from an essential thrombocythaemia (ET) patient harbouring a CALR-Ins5 mutation and from a healthy individual (WT). Megakaryopoiesis was more prominent in Ins5-haematopoietic progenitor cells (Ins5-HPCs) than in WT-HPCs, implying that the system recapitulates megakaryocytosis observed in the bone marrow of CALR-mutant ET patients. Ins5-HPCs exhibited elevated expression levels of GATA1 and GATA2, suggesting a premature commitment to megakaryocytic differentiation in progenitor cells. We also demonstrated that 3-hydroxy anagrelide markedly perturbed megakaryopoiesis, but not erythropoiesis. Collectively, we established an in vitro model system that recapitulates megakaryopoiesis caused by mutant CALR. This system can be used to validate therapeutic compounds for MPN patients harbouring CALR mutations and in detailed studies on mutant CALR in human haematological cell differentiation.

    DOI

  • AldB controls persister formation in Escherichia coli depending on environmental stress

    Yuto Kawai, Shinya Matsumoto, Yiwei Ling, Shujiro Okuda, Satoshi Tsuneda

    Microbiology and Immunology   62 ( 5 ) 299 - 309  2018年05月  [査読有り]

     概要を見る

    Persisters are multidrug-tolerant cells that are present within antibiotic-sensitive populations. Persister formation is not induced by genetic mutations, but rather by changes in the degree of expression of some genes. High redundancy has been observed among the pathways that have been hypothesized to respond to specific stresses. In this study, we conducted RNA sequencing of Escherichia coli persisters under various stress conditions to identify common mechanisms. We induced stresses such as glucose or amino acid exhaustion, acid stress and anaerobic conditions, all of which are encountered during bacterial pathogenesis. We found that most genes are differentially expressed depending on the specific stress condition
    however, some genes were commonly expressed in persisters in most stress conditions. Commonly expressed genes are expected to be promising therapeutic targets for combating persistent infections. We found that knockdown of aldehyde dehydrogenase (aldB), which was expressed in every condition except for acid stress, decreased persisters in the non-stressed condition. However, the same strain unexpectedly showed an increased number of persisters in the amino acid-limited condition. Because the increase in persister number is glycolytic metabolite-dependent, metabolic flow may play a crucial role in aldB-mediated persister formation. These data suggest that environmental stresses alter persister mechanisms. Identification of environmental influences on persister formation during pathogenesis is therefore necessary to enabling persister eradication.

    DOI

  • “All-in-one” in vitro selection of collagen-binding vascular endothelial growth factor

    S.-H. Park, T. Uzawa, F. Hattori, S. Ogino, N. Morimoto, S. Tsuneda, Y. Ito

    Biomaterials   161   270 - 278  2018年04月  [査読有り]  [国際誌]

     概要を見る

    © 2018 Elsevier Ltd To enhance the therapeutic effect of growth factors, a powerful strategy is to direct their localization to damaged sites. To treat skin wounds and myocardial infarction, we selected vascular endothelial growth factor (VEGF) carrying binding affinity to collagen. A simple conjugation of a reported collagen-binding sequence and VEGF did not increase the collagen-binding affinity, indicating that the molecular interaction between the two proteins abolished collagen binding activity. Here, we present a new molecular evolution strategy, “all-in-one” in vitro selection, in which a collagen-binding VEGF (CB-VEGF) was directly identified from a random library consisting of random and VEGF sequences. As expected, the selected CB-VEGFs exhibited high binding affinity to collagen and maintained the same growth enhancement activity for endothelial cells as unmodified VEGF in solution. Furthermore, the selected CB-VEGF enhanced angiogenesis at skin wounds and infarcted myocardium. This study demonstrates that “all-in-one” in vitro selection is a novel strategy for the design of functional proteins for regenerative medicine.

    DOI PubMed

  • “All-in-one” in vitro selection of collagen-binding vascular endothelial growth factor

    Park, Shin Hye, Park, Shin Hye, Uzawa, Takanori, Uzawa, Takanori, Hattori, Fumiyuki, Ogino, Shuichi, Morimoto, Naoki, Tsuneda, Satoshi, Tsuneda, Satoshi, Ito, Yoshihiro, Ito, Yoshihiro, Ito, Yoshihiro

    Biomaterials   161   270 - 278  2018年04月  [国際誌]

     概要を見る

    © 2018 Elsevier Ltd To enhance the therapeutic effect of growth factors, a powerful strategy is to direct their localization to damaged sites. To treat skin wounds and myocardial infarction, we selected vascular endothelial growth factor (VEGF) carrying binding affinity to collagen. A simple conjugation of a reported collagen-binding sequence and VEGF did not increase the collagen-binding affinity, indicating that the molecular interaction between the two proteins abolished collagen binding activity. Here, we present a new molecular evolution strategy, “all-in-one” in vitro selection, in which a collagen-binding VEGF (CB-VEGF) was directly identified from a random library consisting of random and VEGF sequences. As expected, the selected CB-VEGFs exhibited high binding affinity to collagen and maintained the same growth enhancement activity for endothelial cells as unmodified VEGF in solution. Furthermore, the selected CB-VEGF enhanced angiogenesis at skin wounds and infarcted myocardium. This study demonstrates that “all-in-one” in vitro selection is a novel strategy for the design of functional proteins for regenerative medicine.

    DOI PubMed

  • Genomic analysis of two phylogenetically distinct Nitrospira species reveals their genomic plasticity and functional diversity

    Norisuke Ushiki, Hirotsugu Fujitani, Yu Shimada, Tomohiro Morohoshi, Yuji Sekiguchi, Satoshi Tsuneda

    Frontiers in Microbiology   8 ( JAN )  2018年01月

     概要を見る

    The genus Nitrospira represents a dominant group of nitrite-oxidizing bacteria in natural and engineered ecosystems. This genus is phylogenetically divided into six lineages, for which vast phylogenetic and functional diversity has been revealed by recent molecular ecophysiological analyses. However, the genetic basis underlying these phenotypic differences remains largely unknown because of the lack of genome sequences representing their diversity. To gain a more comprehensive understanding of Nitrospira, we performed genomic comparisons between two Nitrospira strains (ND1 and NJ1 belonging to lineages I and II, respectively) previously isolated from activated sludge. In addition, the genomes of these strains were systematically compared with previously reported six Nitrospira genomes to reveal their similarity and presence/absence of several functional genes/operons. Comparisons of Nitrospira genomes indicated that their genomic diversity reflects phenotypic differences and versatile nitrogen metabolisms. Although most genes involved in key metabolic pathways were conserved between strains ND1 and NJ1, assimilatory nitrite reduction pathways of the two Nitrospira strains were different. In addition, the genomes of both strains contain a phylogenetically different urease locus and we confirmed their ureolytic activity. During gene annotation of strain NJ1, we found a gene cluster encoding a quorum-sensing system. From the enriched supernatant of strain NJ1, we successfully identified seven types of acyl-homoserine lactones with a range of C10-C14. In addition, the genome of strain NJ1 lacks genes relevant to flagella and the clustered regularly interspaced short palindromic repeat (CRISPR)-Cas (CRISPR-associated genes) systems, whereas most nitrifying bacteria including strain ND1 possess these genomic elements. These findings enhance our understanding of genomic plasticity and functional diversity among members of the genus Nitrospira.

    DOI

  • Genomic analysis of two phylogenetically distinct Nitrospira species reveals their genomic plasticity and functional diversity

    Norisuke Ushiki, Hirotsugu Fujitani, Yu Shimada, Tomohiro Morohoshi, Yuji Sekiguchi, Satoshi Tsuneda

    Frontiers in Microbiology   8 ( JAN ) 1 - 12  2018年01月

     概要を見る

    The genus Nitrospira represents a dominant group of nitrite-oxidizing bacteria in natural and engineered ecosystems. This genus is phylogenetically divided into six lineages, for which vast phylogenetic and functional diversity has been revealed by recent molecular ecophysiological analyses. However, the genetic basis underlying these phenotypic differences remains largely unknown because of the lack of genome sequences representing their diversity. To gain a more comprehensive understanding of Nitrospira, we performed genomic comparisons between two Nitrospira strains (ND1 and NJ1 belonging to lineages I and II, respectively) previously isolated from activated sludge. In addition, the genomes of these strains were systematically compared with previously reported six Nitrospira genomes to reveal their similarity and presence/absence of several functional genes/operons. Comparisons of Nitrospira genomes indicated that their genomic diversity reflects phenotypic differences and versatile nitrogen metabolisms. Although most genes involved in key metabolic pathways were conserved between strains ND1 and NJ1, assimilatory nitrite reduction pathways of the two Nitrospira strains were different. In addition, the genomes of both strains contain a phylogenetically different urease locus and we confirmed their ureolytic activity. During gene annotation of strain NJ1, we found a gene cluster encoding a quorum-sensing system. From the enriched supernatant of strain NJ1, we successfully identified seven types of acyl-homoserine lactones with a range of C10-C14. In addition, the genome of strain NJ1 lacks genes relevant to flagella and the clustered regularly interspaced short palindromic repeat (CRISPR)-Cas (CRISPR-associated genes) systems, whereas most nitrifying bacteria including strain ND1 possess these genomic elements. These findings enhance our understanding of genomic plasticity and functional diversity among members of the genus Nitrospira.

    DOI

  • Unique transcriptional profile of native persisters in Escherichia coli

    Shinya Matsumoto, Yuto Kawai, Satoshi Miyagawa, Yuka Iwamoto, Shujiro Okuda, Alicia Sánchez-Gorostiaga, Miguel Vicente, Satoshi Tsuneda

    Journal of Bioscience and Bioengineering   125 ( 1 ) 15 - 22  2018年01月

     概要を見る

    Non-dividing persisters, bacteria that can survive in the presence of antibiotics by pausing their metabolic activity, are among the many causes of the refractory nature of bacterial infections. Here we constructed a recombinant Escherichia coli strain that enables to distinguish non-dividing from dividing cell based on Z-ring during cell division. Then, non-dividing cells and dividing cells were successfully separated using a fluorescence activated cell sorter. The sorted non-dividing cells showed significantly higher tolerance toward ofloxacin than dividing cells, which indicates that persisters were concentrated with the methodology. Transcriptional analysis revealed that genes involved in guanosine tetraphosphate synthesis are upregulated in persisters, which represses transcription and DNA replication and leads to ofloxacin tolerance. Lactate dehydrogenase and several ATP-binding cassette transporters were upregulated in persisters to adapt to anaerobic metabolism. In addition, nitrite and dimethyl sulfoxide (DMSO) may be used as reducible substrates for alternative energy generation pathways. Our methodology revealed a unique transcriptional profile of E. coli persisters.

    DOI PubMed

  • Unique transcriptional profile of native persisters in Escherichia coli

    Shinya Matsumoto, Yuto Kawai, Satoshi Miyagawa, Yuka Iwamoto, Shujiro Okuda, Alicia Sánchez-Gorostiaga, Miguel Vicente, Satoshi Tsuneda

    Journal of Bioscience and Bioengineering   125 ( 1 ) 15 - 22  2018年01月  [査読有り]

     概要を見る

    Non-dividing persisters, bacteria that can survive in the presence of antibiotics by pausing their metabolic activity, are among the many causes of the refractory nature of bacterial infections. Here we constructed a recombinant Escherichia coli strain that enables to distinguish non-dividing from dividing cell based on Z-ring during cell division. Then, non-dividing cells and dividing cells were successfully separated using a fluorescence activated cell sorter. The sorted non-dividing cells showed significantly higher tolerance toward ofloxacin than dividing cells, which indicates that persisters were concentrated with the methodology. Transcriptional analysis revealed that genes involved in guanosine tetraphosphate synthesis are upregulated in persisters, which represses transcription and DNA replication and leads to ofloxacin tolerance. Lactate dehydrogenase and several ATP-binding cassette transporters were upregulated in persisters to adapt to anaerobic metabolism. In addition, nitrite and dimethyl sulfoxide (DMSO) may be used as reducible substrates for alternative energy generation pathways. Our methodology revealed a unique transcriptional profile of E. coli persisters.

    DOI PubMed

  • Meta-Analysis of Fecal Microbiota and Metabolites in Experimental Colitic Mice during the Inflammatory and Healing Phases

    Toshifumi Osaka, Eri Moriyama, Shunichi Arai, Yasuhiro Date, Junji Yagi, Jun Kikuchi, Satoshi Tsuneda

    NUTRIENTS   9 ( 12 )  2017年12月  [査読有り]

     概要を見る

    The imbalance of gut microbiota is known to be associated with inflammatory bowel disease, but it remains unknown whether dysbiosis is a cause or consequence of chronic gut inflammation. In order to investigate the effects of gut inflammation on microbiota and metabolome, the sequential changes in gut microbiota and metabolites from the onset of colitis to the recovery in dextran sulfate sodium-induced colitic mice were characterized by using meta 16S rRNA sequencing and proton nuclear magnetic resonance (H-1-NMR) analysis. Mice in the colitis progression phase showed the transient expansions of two bacterial families including Bacteroidaceae and Enterobacteriaceae and the depletion of major gut commensal bacteria belonging to the uncultured Bacteroidales family S24-7, Rikenellaceae, Lachnospiraceae, and Ruminococcaceae. After the initiation of the recovery, commensal Lactobacillus members promptly predominated in gut while other normally abundant bacteria excluding the Erysipelotrichaceae remained diminished. Furthermore, H-1-NMR analysis revealed characteristic fluctuations in fecal levels of organic acids (lactate and succinate) associated with the disease states. In conclusion, acute intestinal inflammation is a perturbation factor of gut microbiota but alters the intestinal environments suitable for Lactobacillus members.

    DOI

  • Meta-Analysis of Fecal Microbiota and Metabolites in Experimental Colitic Mice during the Inflammatory and Healing Phases

    Toshifumi Osaka, Eri Moriyama, Shunichi Arai, Yasuhiro Date, Junji Yagi, Jun Kikuchi, Satoshi Tsuneda

    NUTRIENTS   9 ( 12 ) 1329  2017年12月  [査読有り]

     概要を見る

    The imbalance of gut microbiota is known to be associated with inflammatory bowel disease, but it remains unknown whether dysbiosis is a cause or consequence of chronic gut inflammation. In order to investigate the effects of gut inflammation on microbiota and metabolome, the sequential changes in gut microbiota and metabolites from the onset of colitis to the recovery in dextran sulfate sodium-induced colitic mice were characterized by using meta 16S rRNA sequencing and proton nuclear magnetic resonance (H-1-NMR) analysis. Mice in the colitis progression phase showed the transient expansions of two bacterial families including Bacteroidaceae and Enterobacteriaceae and the depletion of major gut commensal bacteria belonging to the uncultured Bacteroidales family S24-7, Rikenellaceae, Lachnospiraceae, and Ruminococcaceae. After the initiation of the recovery, commensal Lactobacillus members promptly predominated in gut while other normally abundant bacteria excluding the Erysipelotrichaceae remained diminished. Furthermore, H-1-NMR analysis revealed characteristic fluctuations in fecal levels of organic acids (lactate and succinate) associated with the disease states. In conclusion, acute intestinal inflammation is a perturbation factor of gut microbiota but alters the intestinal environments suitable for Lactobacillus members.

    DOI

  • High-rate nitrification of electronic industry wastewater by using nitrifying granules

    Yoshiaki Hasebe, Hiroaki Meguro, Yuuki Kanai, Masahiro Eguchi, Toshifumi Osaka, Satoshi Tsuneda

    WATER SCIENCE AND TECHNOLOGY   76 ( 11 ) 3171 - 3180  2017年12月  [査読有り]

     概要を見る

    Nitrifying granules have a high sedimentation property and an ability to maintain a large amount of nitrifying bacteria in a reaction tank. Our group has examined the formation process of nitrifying granules and achieved high-rate nitrification for an inorganic synthetic wastewater using these granules. In this research, a pilot-scale test plant with an 850-liter reaction tank was assembled in a semiconductor manufacturing factory in order to conduct a continuous water conduction test using real electronics industry wastewater. The aim was to observe the formation of nitrifying granules and determine the maximum ammonia removal rate. The average granule diameter formed during the experiment was 780 mu m and the maximum ammonia removal rate was observed to be 1.5 kgN.m(-3).day(-1) at 20 degrees C, which is 2.5-5 times faster than traditional activated sludge methods. A fluorescence in situ hybridization analysis showed that beta-proteobacterial ammonia oxidizing bacteria and the Nitrospira-like nitrite-oxidizing bacteria dominate the bacteria population in the granules, and their strong aggregation capacity might confer some benefits to the formation of these nitrifying granules.

    DOI

  • Characterization of a Deinococcus radiodurans MazF: A UACA-specific RNA endoribonuclease

    Tatsuki Miyamoto, Yuri Ota, Akiko Yokota, Tetsushi Suyama, Satoshi Tsuneda, Naohiro Noda

    MICROBIOLOGYOPEN   6 ( 5 ) e501  2017年10月  [査読有り]

     概要を見る

    Microbes are known to withstand environmental stresses by using chromosomal toxin-antitoxin systems. MazEF is one of the most extensively studied toxin-antitoxin systems. In stressful environments, MazF toxins modulate translation by cleaving single-stranded RNAs in a sequence-specific fashion. Previously, a chromosomal gene located at DR0417 in Deinococcus radiodurans was predicted to code for a MazF endoribonuclease (MazF(DR0417)); however, its function remains unclear. In the present study, we characterized the molecular function of MazF(DR0417). Analysis of MazF(DR0417)-cleaved RNA sites using modified massively parallel sequencing revealed a unique 4-nt motif, UACA, as a potential cleavage pattern. The activity of MazF(DR0417) was also assessed in a real-time fluorometric assay, which revealed that MazF(DR0417) strictly recognizes the unique tetrad UACA. This sequence specificity may allow D. radiodurans to alter its translation profile and survive under stressful conditions.

    DOI

  • Characterization of a Deinococcus radiodurans MazF: A UACA-specific RNA endoribonuclease

    Tatsuki Miyamoto, Yuri Ota, Akiko Yokota, Tetsushi Suyama, Satoshi Tsuneda, Naohiro Noda

    MICROBIOLOGYOPEN   6 ( 5 ) e501  2017年10月  [査読有り]

     概要を見る

    Microbes are known to withstand environmental stresses by using chromosomal toxin-antitoxin systems. MazEF is one of the most extensively studied toxin-antitoxin systems. In stressful environments, MazF toxins modulate translation by cleaving single-stranded RNAs in a sequence-specific fashion. Previously, a chromosomal gene located at DR0417 in Deinococcus radiodurans was predicted to code for a MazF endoribonuclease (MazF(DR0417)); however, its function remains unclear. In the present study, we characterized the molecular function of MazF(DR0417). Analysis of MazF(DR0417)-cleaved RNA sites using modified massively parallel sequencing revealed a unique 4-nt motif, UACA, as a potential cleavage pattern. The activity of MazF(DR0417) was also assessed in a real-time fluorometric assay, which revealed that MazF(DR0417) strictly recognizes the unique tetrad UACA. This sequence specificity may allow D. radiodurans to alter its translation profile and survive under stressful conditions.

    DOI

  • Enrichment and Physiological Characterization of a Cold-Adapted Nitrite-Oxidizing Nitrotoga sp from an Eelgrass Sediment

    Kento Ishii, Hirotsugu Fujitani, Kentaro Soh, Tatsunori Nakagawa, Reiji Takahashi, Satoshi Tsuneda

    APPLIED AND ENVIRONMENTAL MICROBIOLOGY   83 ( 14 )  2017年07月  [査読有り]

     概要を見る

    Nitrite-oxidizing bacteria (NOB) are responsible for the second step of nitrification in natural and engineered ecosystems. The recently discovered genus Nitrotoga belongs to the Betaproteobacteria and potentially has high environmental importance. Although environmental clones affiliated with Nitrotoga are widely distributed, the limited number of cultivated Nitrotoga spp. results in a poor understanding of their ecophysiological features. In this study, we successfully enriched the nonmarine cold-adapted Nitrotoga sp. strain AM1 from coastal sand in an eelgrass zone and investigated its physiological characteristics. Multistep-enrichment approaches led to an increase in the abundance of AM1 to approximately 80% of the total bacterial population. AM1 was the only detectable NOB in the bacterial community. The 16S rRNA gene sequence of AM1 was 99.6% identical to that of "Candidatus Nitrotoga arctica," which was enriched from permafrost-affected soil. The highest nitrogen oxidation rate of AM1 was observed at 16 degrees C. The half-saturation constant (K-m) and the generation time were determined to be 25 mu M NO2- and 54 h, respectively. The nitrite oxidation rate of AM1 was stimulated at concentrations of &lt;30 mM NH4Cl but completely inhibited at 50 mM NH4Cl. AM1 can grow well under specific environmental conditions, such as low temperature and in the presence of a relatively high concentration of free ammonia. These results help improve our comprehension of the functional importance of Nitrotoga.
    IMPORTANCE Nitrite-oxidizing bacteria (NOB) are key players in the second step of nitrification, which is an important process of the nitrogen cycle. Recent studies have suggested that the organisms of the novel NOB genus Nitrotoga were widely distributed and played a functional role in natural and engineered ecosystems. However, only a few Nitrotoga enrichments have been obtained, and little is known about their ecology and physiology. In this study, we successfully enriched a Nitrotoga sp. from sand in a shallow coastal marine ecosystem and undertook a physiological characterization. The laboratory experiments showed that the Nitrotoga enrichment culture could adapt not only to low temperature but also to relatively high concentrations of free ammonia. The determination of as-yet-unknown unique characteristics of Nitrotoga contributes to the improvement of our insights into the microbiology of nitrification.

    DOI PubMed

  • Enrichment and Physiological Characterization of a Cold-Adapted Nitrite-Oxidizing Nitrotoga sp from an Eelgrass Sediment

    Kento Ishii, Hirotsugu Fujitani, Kentaro Soh, Tatsunori Nakagawa, Reiji Takahashi, Satoshi Tsuneda

    APPLIED AND ENVIRONMENTAL MICROBIOLOGY   83 ( 14 ) e00549-17  2017年07月  [査読有り]

     概要を見る

    Nitrite-oxidizing bacteria (NOB) are responsible for the second step of nitrification in natural and engineered ecosystems. The recently discovered genus Nitrotoga belongs to the Betaproteobacteria and potentially has high environmental importance. Although environmental clones affiliated with Nitrotoga are widely distributed, the limited number of cultivated Nitrotoga spp. results in a poor understanding of their ecophysiological features. In this study, we successfully enriched the nonmarine cold-adapted Nitrotoga sp. strain AM1 from coastal sand in an eelgrass zone and investigated its physiological characteristics. Multistep-enrichment approaches led to an increase in the abundance of AM1 to approximately 80% of the total bacterial population. AM1 was the only detectable NOB in the bacterial community. The 16S rRNA gene sequence of AM1 was 99.6% identical to that of "Candidatus Nitrotoga arctica," which was enriched from permafrost-affected soil. The highest nitrogen oxidation rate of AM1 was observed at 16 degrees C. The half-saturation constant (K-m) and the generation time were determined to be 25 mu M NO2- and 54 h, respectively. The nitrite oxidation rate of AM1 was stimulated at concentrations of &lt;30 mM NH4Cl but completely inhibited at 50 mM NH4Cl. AM1 can grow well under specific environmental conditions, such as low temperature and in the presence of a relatively high concentration of free ammonia. These results help improve our comprehension of the functional importance of Nitrotoga.
    IMPORTANCE Nitrite-oxidizing bacteria (NOB) are key players in the second step of nitrification, which is an important process of the nitrogen cycle. Recent studies have suggested that the organisms of the novel NOB genus Nitrotoga were widely distributed and played a functional role in natural and engineered ecosystems. However, only a few Nitrotoga enrichments have been obtained, and little is known about their ecology and physiology. In this study, we successfully enriched a Nitrotoga sp. from sand in a shallow coastal marine ecosystem and undertook a physiological characterization. The laboratory experiments showed that the Nitrotoga enrichment culture could adapt not only to low temperature but also to relatively high concentrations of free ammonia. The determination of as-yet-unknown unique characteristics of Nitrotoga contributes to the improvement of our insights into the microbiology of nitrification.

    DOI

  • First full-scale nitritation-anammox plant using gel entrapment technology for ammonia plant effluent

    Kazuichi Isaka, Yuya Kimura, Masahiro Matsuura, Toshifumi Osaka, Satoshi Tsuneda

    BIOCHEMICAL ENGINEERING JOURNAL   122   115 - 122  2017年06月  [査読有り]

     概要を見る

    The first full-scale nitritation-anammox process using gel entrapment technology was evaluated for nitrogen removal. Ammonia plant effluents contained not only ammonium but also methanol, an anammox inhibitor. The nitrogen concentration and loading design were 690 mg/L and 400 kg-N/d, respectively. A nitritation reactor (170 m(3)) filled with nitrification gel carriers was started up on day 20, with a resulting nitrification efficiency of 58%. A stable nitritation performance was observed without significant nitrate production for &gt;1 year. A nitrogen conversion rate of 3.2 kg-N/m(3)/d was observed on the anammox reactor (100 m3) filled with anammox gel carrier on day 69. The full-scale anammox reactor could be started up in approximately 2 months. Subsequently, stable nitrogen removal performance was observed for &gt;1 year. The average nitrogen loading, nitrogen conversion rate, and total nitrogen removal on the anammox reactor were 3.6 kg-N/m(3)/d, 3.0 kg-N/m(3)/d and 330 kg-N/d, respectively. The nitrogen removal performance obtained in this study will facilitate further application of the anammox processes to many types of industrial wastewater treatment. (C) 2017 Elsevier B.V. All rights reserved.

    DOI

  • First full-scale nitritation-anammox plant using gel entrapment technology for ammonia plant effluent

    Kazuichi Isaka, Yuya Kimura, Masahiro Matsuura, Toshifumi Osaka, Satoshi Tsuneda

    BIOCHEMICAL ENGINEERING JOURNAL   122   115 - 122  2017年06月  [査読有り]

     概要を見る

    The first full-scale nitritation-anammox process using gel entrapment technology was evaluated for nitrogen removal. Ammonia plant effluents contained not only ammonium but also methanol, an anammox inhibitor. The nitrogen concentration and loading design were 690 mg/L and 400 kg-N/d, respectively. A nitritation reactor (170 m(3)) filled with nitrification gel carriers was started up on day 20, with a resulting nitrification efficiency of 58%. A stable nitritation performance was observed without significant nitrate production for &gt;1 year. A nitrogen conversion rate of 3.2 kg-N/m(3)/d was observed on the anammox reactor (100 m3) filled with anammox gel carrier on day 69. The full-scale anammox reactor could be started up in approximately 2 months. Subsequently, stable nitrogen removal performance was observed for &gt;1 year. The average nitrogen loading, nitrogen conversion rate, and total nitrogen removal on the anammox reactor were 3.6 kg-N/m(3)/d, 3.0 kg-N/m(3)/d and 330 kg-N/d, respectively. The nitrogen removal performance obtained in this study will facilitate further application of the anammox processes to many types of industrial wastewater treatment. (C) 2017 Elsevier B.V. All rights reserved.

    DOI

  • Nitrite oxidation kinetics of two Nitrospira strains: The quest for competition and ecological niche differentiation

    Norisuke Ushiki, Masaru Jinno, Hirotsugu Fujitani, Toshikazu Suenaga, Akihiko Terada, Satoshi Tsuneda

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   123 ( 5 ) 581 - 589  2017年05月  [査読有り]

     概要を見る

    Nitrite oxidation is an aerobic process of the nitrogen cycle in natural ecosystems, and is performed by nitrite-oxidizing bacteria (NOB). Also, nitrite oxidation is a rate-limiting step of nitrogen removal in wastewater treatment plants (WWTPs). Although Nitrospira is known as dominant NOB in WWTPs, information on their physiological properties and kinetic parameters is limited. Here, we report the kinetic parameters and inhibition of nitrite oxidation by free ammonia in pure cultures of Nitrospira sp. strain ND1 and Nitrospira japonica strain NJ1, which were previously isolated from activated sludge in a WWTP. The maximum nitrite uptake rate (V-max_NO2) and the half-saturation constant for nitrite uptake (K-m_NO2) of strains ND1 and NJ1 were 45 +/- 7 and 31 +/- 5 (mu mol NO2-/mg protein/h), and 6 +/- 1 and 10 +/- 2 (mu M NO2-), respectively. The V-max_NO2 and K-m_NO2 of two strains indicated that they adapt to low-nitrite-concentration environments like activated sludge. The half-saturation constants for oxygen uptake (K-m_O2) of the two strains were 4.0 +/- 2.5 and 2.6 +/- 1.1 (mu M O-2), respectively. The K-m_O2 values of the two strains were lower than those of other NOB, suggesting that Nitrospira in activated sludge could oxidize nitrite in the hypoxic environments often found in the interiors of biofilms and flocs. The inhibition thresholds of the two strains by free ammonia were 0.85 and 4.3 (mg-NH3 I-1), respectively. Comparing the physiological properties of the two strains, we suggest that tolerance for free ammonia determines competition and partitioning into ecological niches among Nitrospira populations. (C) 2017, The Society for Biotechnology, Japan. All rights reserved.

    DOI PubMed

  • Real-time quantitation of internal metabolic activity of three-dimensional engineered tissues using an oxygen microelectrode and optical coherence tomography

    Yuki Kagawa, Yuji Haraguchi, Satoshi Tsuneda, Tatsuya Shimizu

    JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS   105 ( 4 ) 855 - 864  2017年05月

     概要を見る

    Recent progress in tissue engineering technology has enabled us to develop thick tissue constructs that can then be transplanted in regenerative therapies. In clinical situations, it is vital that the engineered tissues to be implanted are safe and functional before use. However, there is currently a limited number of studies on real-time quality evaluation of thick living tissue constructs. Here we developed a system for quantifying the internal activities of engineered tissues, from which we can evaluate its quality in real-time. The evaluation was achieved by measuring oxygen concentration profiles made along the vertical axis and the thickness of the tissues estimated from cross-sectional images obtained noninvasively by an optical coherence tomography system. Using our novel system, we obtained (i) oxygen concentration just above the tissues, (ii) gradient of oxygen along vertical axis formed above the tissues within culture medium, and (iii) gradient of oxygen formed within the tissues in real-time. Investigating whether these three parameters could be used to evaluate engineered tissues during culturing, we found that only the third parameter was a good candidate. This implies that the activity of living engineered tissues can be monitored in real-time by measuring the oxygen gradient within the tissues. The proposed measuring strategy can be applied to developing more efficient culturing methods to support the fabrication of engineered thick tissues, as well as providing methods to confirm the quality in real-time. (c) 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 855-864, 2017.

    DOI

  • Nitrite oxidation kinetics of two Nitrospira strains: The quest for competition and ecological niche differentiation

    Norisuke Ushiki, Masaru Jinno, Hirotsugu Fujitani, Toshikazu Suenaga, Akihiko Terada, Satoshi Tsuneda

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   123 ( 5 ) 581 - 589  2017年05月  [査読有り]

     概要を見る

    Nitrite oxidation is an aerobic process of the nitrogen cycle in natural ecosystems, and is performed by nitrite-oxidizing bacteria (NOB). Also, nitrite oxidation is a rate-limiting step of nitrogen removal in wastewater treatment plants (WWTPs). Although Nitrospira is known as dominant NOB in WWTPs, information on their physiological properties and kinetic parameters is limited. Here, we report the kinetic parameters and inhibition of nitrite oxidation by free ammonia in pure cultures of Nitrospira sp. strain ND1 and Nitrospira japonica strain NJ1, which were previously isolated from activated sludge in a WWTP. The maximum nitrite uptake rate (V-max_NO2) and the half-saturation constant for nitrite uptake (K-m_NO2) of strains ND1 and NJ1 were 45 +/- 7 and 31 +/- 5 (mu mol NO2-/mg protein/h), and 6 +/- 1 and 10 +/- 2 (mu M NO2-), respectively. The V-max_NO2 and K-m_NO2 of two strains indicated that they adapt to low-nitrite-concentration environments like activated sludge. The half-saturation constants for oxygen uptake (K-m_O2) of the two strains were 4.0 +/- 2.5 and 2.6 +/- 1.1 (mu M O-2), respectively. The K-m_O2 values of the two strains were lower than those of other NOB, suggesting that Nitrospira in activated sludge could oxidize nitrite in the hypoxic environments often found in the interiors of biofilms and flocs. The inhibition thresholds of the two strains by free ammonia were 0.85 and 4.3 (mg-NH3 I-1), respectively. Comparing the physiological properties of the two strains, we suggest that tolerance for free ammonia determines competition and partitioning into ecological niches among Nitrospira populations. (C) 2017, The Society for Biotechnology, Japan. All rights reserved.

    DOI

  • Real-time quantitation of internal metabolic activity of three-dimensional engineered tissues using an oxygen microelectrode and optical coherence tomography

    Yuki Kagawa, Yuji Haraguchi, Satoshi Tsuneda, Tatsuya Shimizu

    JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS   105 ( 4 ) 855 - 864  2017年05月  [査読有り]

     概要を見る

    Recent progress in tissue engineering technology has enabled us to develop thick tissue constructs that can then be transplanted in regenerative therapies. In clinical situations, it is vital that the engineered tissues to be implanted are safe and functional before use. However, there is currently a limited number of studies on real-time quality evaluation of thick living tissue constructs. Here we developed a system for quantifying the internal activities of engineered tissues, from which we can evaluate its quality in real-time. The evaluation was achieved by measuring oxygen concentration profiles made along the vertical axis and the thickness of the tissues estimated from cross-sectional images obtained noninvasively by an optical coherence tomography system. Using our novel system, we obtained (i) oxygen concentration just above the tissues, (ii) gradient of oxygen along vertical axis formed above the tissues within culture medium, and (iii) gradient of oxygen formed within the tissues in real-time. Investigating whether these three parameters could be used to evaluate engineered tissues during culturing, we found that only the third parameter was a good candidate. This implies that the activity of living engineered tissues can be monitored in real-time by measuring the oxygen gradient within the tissues. The proposed measuring strategy can be applied to developing more efficient culturing methods to support the fabrication of engineered thick tissues, as well as providing methods to confirm the quality in real-time. (c) 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 855-864, 2017.

    DOI

  • Four Aromatic Sulfates with an Inhibitory Effect against HCV NS3 Helicase from the Crinoid Alloeocomatella polycladia

    Idam Hermawan, Atsushi Furuta, Masahiro Higashi, Yoshihisa Fujita, Nobuyoshi Akimitsu, Atsuya Yamashita, Kohji Moriishi, Satoshi Tsuneda, Hidenori Tani, Masamichi Nakakoshi, Masayoshi Tsubuki, Yuji Sekiguchi, Naohiro Noda, Junichi Tanaka

    MARINE DRUGS   15 ( 4 )  2017年04月  [査読有り]

     概要を見る

    Bioassay-guided separation of a lipophilic extract of the crinoid Alloeocomatella polycladia, inhibiting the activity of HCV NS3 helicase, yielded two groups of molecules: cholesterol sulfate and four new aromatic sulfates 1-4. The structures of the aromatics were elucidated by spectroscopic analysis in addition to theoretical studies. The aromatic sulfates 1-4 showed moderate inhibition against NS3 helicase with IC50 values of 71, 95, 7, and 5 mu M, respectively.

    DOI

  • pH-gradient ion-exchange microbial cell chromatography as a simple method for microbial separation

    Yoshiteru Aoi, Yuji Kaneko, Satoshi Tsuneda

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   123 ( 4 ) 431 - 436  2017年04月  [査読有り]

     概要を見る

    Selective separation of specific microbial types from a heterogeneous microbial population, such as an environmental microbial community, is an important process for microbial research and biotechnological industries. In the present study, pH-gradient ion-exchange microbial cell chromatography (PIE-MCC) was developed as a new method for microbial separation. The proposed method enables target microorganisms to be separated from a microbial community based on differences in microbial surface characteristics, because these characteristics, such as the zeta (zeta)-potential, vary among microbial cells. PIE-MCC was conducted by controlling the adhesion and detachment of microbial cells to and from the carrier surface by manipulating the pH of the running buffer. As a proof of concept, microbial cell separation via PIE-MCC was demonstrated using pure-cultured strains, model mixtures of two different pure-cultured strains, and an environmental sample targeting uncultivated microorganisms; i.e., each pure-cultured strain showed unique chromatograms; specific single species were separated from the model mixture; and a specific, uncultivated target was separated from the environmental sample. The zeta-potential of several tested strains suggested that not only electrostatic interactions, but also other factors affected microbial adhesion to the carrier surface. The newly developed method has several potential advantages compared with other techniques, not only in terms of its microbial separation capability, but also in terms of its simplicity and ability to be scaled up. Thus, the method has the potential to be widely used for a variety of purposes in the microbiology and biotechnology fields. (C) 2016, The Society for Biotechnology, Japan. All rights reserved.

    DOI PubMed

  • pH-gradient ion-exchange microbial cell chromatography as a simple method for microbial separation

    Yoshiteru Aoi, Yuji Kaneko, Satoshi Tsuneda

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   123 ( 4 ) 431 - 436  2017年04月  [査読有り]

     概要を見る

    Selective separation of specific microbial types from a heterogeneous microbial population, such as an environmental microbial community, is an important process for microbial research and biotechnological industries. In the present study, pH-gradient ion-exchange microbial cell chromatography (PIE-MCC) was developed as a new method for microbial separation. The proposed method enables target microorganisms to be separated from a microbial community based on differences in microbial surface characteristics, because these characteristics, such as the zeta (zeta)-potential, vary among microbial cells. PIE-MCC was conducted by controlling the adhesion and detachment of microbial cells to and from the carrier surface by manipulating the pH of the running buffer. As a proof of concept, microbial cell separation via PIE-MCC was demonstrated using pure-cultured strains, model mixtures of two different pure-cultured strains, and an environmental sample targeting uncultivated microorganisms; i.e., each pure-cultured strain showed unique chromatograms; specific single species were separated from the model mixture; and a specific, uncultivated target was separated from the environmental sample. The zeta-potential of several tested strains suggested that not only electrostatic interactions, but also other factors affected microbial adhesion to the carrier surface. The newly developed method has several potential advantages compared with other techniques, not only in terms of its microbial separation capability, but also in terms of its simplicity and ability to be scaled up. Thus, the method has the potential to be widely used for a variety of purposes in the microbiology and biotechnology fields. (C) 2016, The Society for Biotechnology, Japan. All rights reserved.

    DOI

  • Four Aromatic Sulfates with an Inhibitory Effect against HCV NS3 Helicase from the Crinoid Alloeocomatella polycladia

    Idam Hermawan, Atsushi Furuta, Masahiro Higashi, Yoshihisa Fujita, Nobuyoshi Akimitsu, Atsuya Yamashita, Kohji Moriishi, Satoshi Tsuneda, Hidenori Tani, Masamichi Nakakoshi, Masayoshi Tsubuki, Yuji Sekiguchi, Naohiro Noda, Junichi Tanaka

    MARINE DRUGS   15 ( 4 ) 1 - 10  2017年04月  [査読有り]

     概要を見る

    Bioassay-guided separation of a lipophilic extract of the crinoid Alloeocomatella polycladia, inhibiting the activity of HCV NS3 helicase, yielded two groups of molecules: cholesterol sulfate and four new aromatic sulfates 1-4. The structures of the aromatics were elucidated by spectroscopic analysis in addition to theoretical studies. The aromatic sulfates 1-4 showed moderate inhibition against NS3 helicase with IC50 values of 71, 95, 7, and 5 mu M, respectively.

    DOI

  • A rapid collection of yet unknown ammonia oxidizers in pure culture from activated sludge

    Takuma Abe, Norisuke Ushiki, Hirotsugu Fujitani, Satoshi Tsuneda

    WATER RESEARCH   108 ( 1 ) 169 - 178  2017年01月  [査読有り]

     概要を見る

    Nitrification is an important reaction in the biological nitrogen removal process in wastewater treatment plants (WWTPs). As ammonia-oxidizing microbes are slow-growing and sensitive to environmental factors such as free ammonia, pure strains are hard to obtain, preventing our understanding of their physiological characteristics. To conquer this hurdle, we report a high-throughput isolation technique based on scattering signatures, which exploits the tendency of many ammonia-oxidizing bacteria (AOB) to form microcolonies in activated sludge. The AOB microcolonies were directly sorted from the activated sludge without long incubation and enrichment bias, and were sequentially inoculated into 96-well microtiter plates containing growth medium. Phylogenetic analysis of the pure strains isolated in this study revealed a deeply branching and unrecognized lineage and diversity within the genus Nitrosomonas, beyond our expectation. (C) 2016 Elsevier Ltd. All rights reserved.

    DOI

  • A rapid collection of yet unknown ammonia oxidizers in pure culture from activated sludge

    Takuma Abe, Norisuke Ushiki, Hirotsugu Fujitani, Satoshi Tsuneda

    WATER RESEARCH   108 ( 1 ) 169 - 178  2017年01月  [査読有り]

     概要を見る

    Nitrification is an important reaction in the biological nitrogen removal process in wastewater treatment plants (WWTPs). As ammonia-oxidizing microbes are slow-growing and sensitive to environmental factors such as free ammonia, pure strains are hard to obtain, preventing our understanding of their physiological characteristics. To conquer this hurdle, we report a high-throughput isolation technique based on scattering signatures, which exploits the tendency of many ammonia-oxidizing bacteria (AOB) to form microcolonies in activated sludge. The AOB microcolonies were directly sorted from the activated sludge without long incubation and enrichment bias, and were sequentially inoculated into 96-well microtiter plates containing growth medium. Phylogenetic analysis of the pure strains isolated in this study revealed a deeply branching and unrecognized lineage and diversity within the genus Nitrosomonas, beyond our expectation. (C) 2016 Elsevier Ltd. All rights reserved.

    DOI

  • Ecophysiology and Comparative Genomics of Nitrosomonas mobilis Ms1 Isolated from Autotrophic Nitrifying Granules of Wastewater Treatment Bioreactor

    Soe Myat Thandar, Norisuke Ushiki, Hirotsugu Fujitani, Yuji Sekiguchi, Satoshi Tsuneda

    FRONTIERS IN MICROBIOLOGY   7 ( NOV )  2016年11月  [査読有り]

     概要を見る

    Ammonia-oxidizing bacteria (AOB), which oxidize ammonia to nitrite in the first step of nitrification, play an important role in biological wastewater treatment systems. Nitrosomonas mobilis is an important and dominant AOB in various wastewater treatment systems. However, the detailed physiological and genomic properties of N. mobilis have not been thoroughly investigated because of limited success isolating pure cultures. This study investigated the key physiological characteristics of N. mobilis Ms1, which was previously isolated into pure culture from the nitrifying granules of wastewater treatment bioreactor. The pure culture of N. mobilis Ms1 was cultivated in liquid mineral medium with 30 mg-NL-1 (2.14 mM) of ammonium at room temperature under dark conditions. The optimum growth of N. mobilis Ms1 occurred at 27 degrees C and pH 8, with a maximum growth rate of 0.05-0.07 h(-1), which corresponded to a generation time of 10-14 h. The half saturation constant for ammonium uptake rate and the maximum ammonium uptake rate of N. mobilis Ms1 were 30.70 +/- 0.51 mu M NH4+ and 0.01 +/- 0.002 pmol NH4+ cells(-1) h(-1), respectively. N. mobilis Ms1 had higher ammonia oxidation activity than N. europaea in this study. The oxygen uptake activity kinetics of N. mobilis Ms1 were K-m(O2) = 21.74 +/- 4.01 it mu M O-2 and V-max(O2) = 0.06 +/- 0.02 pmol O-2 cells(-1) h(-1). Ms1 grew well at ammonium and NaCl concentrations of up to 100 and 500 mM, respectively. The nitrite tolerance of N. mobilis Ms1 was extremely high (up to 300 mM) compared to AOB previously isolated from activated sludge and wastewater treatment plants. The average nucleotide identity between the genomes of N. mobilis Ms1 and other Nitrosomonas species indicated that N. mobilis Ms1 was distantly related to other Nitrosomonas species. The organization of the genes encoding protein inventory involved in ammonia oxidation and nitrifier denitrification processes were different from other Nitrosomonas species. The current study provides a needed physiological and genomic characterization of N. mobilis-like bacteria and a better understanding of their ecophysiological properties, enabling comparison of these bacteria with other AOB in wastewater treatment systems and natural ecosystems.

    DOI

  • Ecophysiology and Comparative Genomics of Nitrosomonas mobilis Ms1 Isolated from Autotrophic Nitrifying Granules of Wastewater Treatment Bioreactor

    Soe Myat Thandar, Norisuke Ushiki, Hirotsugu Fujitani, Yuji Sekiguchi, Satoshi Tsuneda

    FRONTIERS IN MICROBIOLOGY   7 ( NOV )  2016年11月  [査読有り]

     概要を見る

    Ammonia-oxidizing bacteria (AOB), which oxidize ammonia to nitrite in the first step of nitrification, play an important role in biological wastewater treatment systems. Nitrosomonas mobilis is an important and dominant AOB in various wastewater treatment systems. However, the detailed physiological and genomic properties of N. mobilis have not been thoroughly investigated because of limited success isolating pure cultures. This study investigated the key physiological characteristics of N. mobilis Ms1, which was previously isolated into pure culture from the nitrifying granules of wastewater treatment bioreactor. The pure culture of N. mobilis Ms1 was cultivated in liquid mineral medium with 30 mg-NL-1 (2.14 mM) of ammonium at room temperature under dark conditions. The optimum growth of N. mobilis Ms1 occurred at 27 degrees C and pH 8, with a maximum growth rate of 0.05-0.07 h(-1), which corresponded to a generation time of 10-14 h. The half saturation constant for ammonium uptake rate and the maximum ammonium uptake rate of N. mobilis Ms1 were 30.70 +/- 0.51 mu M NH4+ and 0.01 +/- 0.002 pmol NH4+ cells(-1) h(-1), respectively. N. mobilis Ms1 had higher ammonia oxidation activity than N. europaea in this study. The oxygen uptake activity kinetics of N. mobilis Ms1 were K-m(O2) = 21.74 +/- 4.01 it mu M O-2 and V-max(O2) = 0.06 +/- 0.02 pmol O-2 cells(-1) h(-1). Ms1 grew well at ammonium and NaCl concentrations of up to 100 and 500 mM, respectively. The nitrite tolerance of N. mobilis Ms1 was extremely high (up to 300 mM) compared to AOB previously isolated from activated sludge and wastewater treatment plants. The average nucleotide identity between the genomes of N. mobilis Ms1 and other Nitrosomonas species indicated that N. mobilis Ms1 was distantly related to other Nitrosomonas species. The organization of the genes encoding protein inventory involved in ammonia oxidation and nitrifier denitrification processes were different from other Nitrosomonas species. The current study provides a needed physiological and genomic characterization of N. mobilis-like bacteria and a better understanding of their ecophysiological properties, enabling comparison of these bacteria with other AOB in wastewater treatment systems and natural ecosystems.

    DOI

  • Ecophysiology and Comparative Genomics of Nitrosomonas mobilis Ms1 Isolated from Autotrophic Nitrifying Granules of Wastewater Treatment Bioreactor

    Soe Myat Thandar, Norisuke Ushiki, Hirotsugu Fujitani, Yuji Sekiguchi, Satoshi Tsuneda

    FRONTIERS IN MICROBIOLOGY   7 ( 1869 ) 1 - 14  2016年11月  [査読有り]

     概要を見る

    Ammonia-oxidizing bacteria (AOB), which oxidize ammonia to nitrite in the first step of nitrification, play an important role in biological wastewater treatment systems. Nitrosomonas mobilis is an important and dominant AOB in various wastewater treatment systems. However, the detailed physiological and genomic properties of N. mobilis have not been thoroughly investigated because of limited success isolating pure cultures. This study investigated the key physiological characteristics of N. mobilis Ms1, which was previously isolated into pure culture from the nitrifying granules of wastewater treatment bioreactor. The pure culture of N. mobilis Ms1 was cultivated in liquid mineral medium with 30 mg-NL-1 (2.14 mM) of ammonium at room temperature under dark conditions. The optimum growth of N. mobilis Ms1 occurred at 27 degrees C and pH 8, with a maximum growth rate of 0.05-0.07 h(-1), which corresponded to a generation time of 10-14 h. The half saturation constant for ammonium uptake rate and the maximum ammonium uptake rate of N. mobilis Ms1 were 30.70 +/- 0.51 mu M NH4+ and 0.01 +/- 0.002 pmol NH4+ cells(-1) h(-1), respectively. N. mobilis Ms1 had higher ammonia oxidation activity than N. europaea in this study. The oxygen uptake activity kinetics of N. mobilis Ms1 were K-m(O2) = 21.74 +/- 4.01 it mu M O-2 and V-max(O2) = 0.06 +/- 0.02 pmol O-2 cells(-1) h(-1). Ms1 grew well at ammonium and NaCl concentrations of up to 100 and 500 mM, respectively. The nitrite tolerance of N. mobilis Ms1 was extremely high (up to 300 mM) compared to AOB previously isolated from activated sludge and wastewater treatment plants. The average nucleotide identity between the genomes of N. mobilis Ms1 and other Nitrosomonas species indicated that N. mobilis Ms1 was distantly related to other Nitrosomonas species. The organization of the genes encoding protein inventory involved in ammonia oxidation and nitrifier denitrification processes were different from other Nitrosomonas species. The current study provides a needed physiological and genomic characterization of N. mobilis-like bacteria and a better understanding of their ecophysiological properties, enabling comparison of these bacteria with other AOB in wastewater treatment systems and natural ecosystems.

    DOI

  • Physical enrichment of uncultured Accumulibacter and Nitrospira from activated sludge by unlabeled cell sorting technique

    Kana Irie, Hirotsugu Fujitani, Satoshi Tsuneda

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   122 ( 4 ) 475 - 481  2016年10月  [査読有り]

     概要を見る

    It is important to understand the ecology and physiology of microbes in activated sludge of wastewater treatment plants. Recently, molecular based approaches such as 16S rRNA genes and environmental genomics have illuminated black boxes in nutrient removal process and expanded our knowledge. However, most microbes responsible for the removal of phosphate and nitrogen such as Accumulibacter and Nitrospira remain uncultured. This is because optimum methodologies to concentrate these uncultured microbes and to obtain pure cultures have not been established. Here, we report a novel approach for physical enrichment of uncultured Accumulibacter and Nitrospira from microbial communities in activated sludge by a cell sorting system. Two scattering signatures representing forward scatter and side scatter of this system allowed morphological characterization of microbial particles in activated sludge. The distribution and size of microbial particles consisting of single cells, microcolonies, and aggregates depended on the levels of scattering signatures. Next generation sequencer and principal component analysis revealed each microbial population fractionated according to the levels of scattering signatures, resulting that uncultured Accumulibacter and Nitrospira could be sorted as single cells or microcolonies. Finally, quantitative fluorescence in situ hybridization analysis determined optimum fractions to collect sufficiently these target microbes from activated sludge. Consequently, this method would be very useful as an enrichment technique prior to isolation, genomic analysis, and physiological investigation of uncultured bacteria. (C) 2016, The Society for Biotechnology, Japan. All rights reserved.

    DOI

  • Physical enrichment of uncultured Accumulibacter and Nitrospira from activated sludge by unlabeled cell sorting technique

    Kana Irie, Hirotsugu Fujitani, Satoshi Tsuneda

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   122 ( 4 ) 475 - 481  2016年10月  [査読有り]

     概要を見る

    It is important to understand the ecology and physiology of microbes in activated sludge of wastewater treatment plants. Recently, molecular based approaches such as 16S rRNA genes and environmental genomics have illuminated black boxes in nutrient removal process and expanded our knowledge. However, most microbes responsible for the removal of phosphate and nitrogen such as Accumulibacter and Nitrospira remain uncultured. This is because optimum methodologies to concentrate these uncultured microbes and to obtain pure cultures have not been established. Here, we report a novel approach for physical enrichment of uncultured Accumulibacter and Nitrospira from microbial communities in activated sludge by a cell sorting system. Two scattering signatures representing forward scatter and side scatter of this system allowed morphological characterization of microbial particles in activated sludge. The distribution and size of microbial particles consisting of single cells, microcolonies, and aggregates depended on the levels of scattering signatures. Next generation sequencer and principal component analysis revealed each microbial population fractionated according to the levels of scattering signatures, resulting that uncultured Accumulibacter and Nitrospira could be sorted as single cells or microcolonies. Finally, quantitative fluorescence in situ hybridization analysis determined optimum fractions to collect sufficiently these target microbes from activated sludge. Consequently, this method would be very useful as an enrichment technique prior to isolation, genomic analysis, and physiological investigation of uncultured bacteria. (C) 2016, The Society for Biotechnology, Japan. All rights reserved.

    DOI

  • AAU-Specific RNA Cleavage Mediated by MazF Toxin Endoribonuclease Conserved in Nitrosomonas europaea

    Tatsuki Miyamoto, Akiko Yokota, Satoshi Tsuneda, Naohiro Noda

    TOXINS   8 ( 6 ) n° 174  2016年06月  [査読有り]

     概要を見る

    Nitrosomonas europaea carries numerous toxin-antitoxin systems. However, despite the abundant representation in its chromosome, studies have not surveyed the underlying molecular functions in detail, and their biological roles remain enigmatic. In the present study, we found that a chromosomally-encoded MazF family member, predicted at the locus NE1181, is a functional toxin endoribonuclease, and constitutes a toxin-antitoxin system, together with its cognate antitoxin, MazE. Massive parallel sequencing provided strong evidence that this toxin endoribonuclease exhibits RNA cleavage activity, primarily against the AAU triplet. This sequence-specificity was supported by the results of fluorometric assays. Our results indicate that N. europaea alters the translation profile and regulates its growth using the MazF family of endoribonuclease under certain stressful conditions.

    DOI

  • Characterization of MazF-Mediated Sequence-Specific RNA Cleavage in Pseudomonas putida Using Massive Parallel Sequencing

    Tatsuki Miyamoto, Yuka Kato, Yuji Sekiguchi, Satoshi Tsuneda, Naohiro Noda

    PLOS ONE   11 ( 2 ) e0149494  2016年02月  [査読有り]

     概要を見る

    Under environmental stress, microbes are known to alter their translation patterns using sequence-specific endoribonucleases that we call RNA interferases. However, there has been limited insight regarding which RNAs are specifically cleaved by these RNA interferases, hence their physiological functions remain unknown. In the current study, we developed a novel method to effectively identify cleavage specificities with massive parallel sequencing. This approach uses artificially designed RNAs composed of diverse sequences, which do not form extensive secondary structures, and it correctly identified the cleavage sequence of a well-characterized Escherichia coli RNA interferase, MazF, as ACA. In addition, we also determined that an uncharacterized MazF homologue isolated from Pseudomonas putida specifically recognizes the unique triplet, UAC. Using a real-time fluorescence resonance energy transfer assay, the UAC triplet was further proved to be essential for cleavage in P. putida MazF. These results highlight an effective method to determine cleavage specificity of RNA interferases.

    DOI

  • Effect of Lipopolysaccharide on the Progression of Non-Alcoholic Fatty Liver Disease in High Caloric Diet-Fed Mice

    N. Matsushita, T. Osaka, I. Haruta, H. Ueshiba, N. Yanagisawa, M. Omori-Miyake, E. Hashimoto, N. Shibata, K. Tokushige, K. Saito, S. Tsuneda, J. Yagi

    SCANDINAVIAN JOURNAL OF IMMUNOLOGY   83 ( 2 ) 109 - 118  2016年02月  [査読有り]

     概要を見る

    The incidence of non-alcoholic steatohepatitis (NASH) is increasing. Because gut microbiota have been highlighted as one of the key factors in the pathogenesis of metabolic syndrome, we investigated the involvement of the bacterial component in the progression of non-alcoholic fatty liver (NAFL) to NASH. C57BL/6 mice were fed with maintenance food (MF, groups A and B) or a high caloric diet (HCD, groups C and D) for 1month. Mice were then divided into four groups: Groups A and C were inoculated with PBS, while groups B and D were inoculated with lipopolysaccharide (LPS) plus complete Freund's adjuvant (CFA). The inoculations were performed a total of 3 times over 3months. At 6months, while hepatic steatosis was observed in groups C and D, cellular infiltration and fibrosis were less evident in group C than in group D. Inflammatory cytokines were upregulated in groups B and D. 16S rRNA pyrosequencing of whole colon homogenates containing faeces showed that certain bacterial groups, such as Bacteroidaceae, Peptostreptococcaceae and Erysipelotrichaceae, were increased in groups C and D. Although loading of bacterial components (LPS) resulted in hepatic inflammation in both MF- and HCD-fed mice, HCD feeding was more crucial in the progression of NAFL during the triggering phase.

    DOI PubMed

  • System for measuring oxygen consumption rates of mammalian cells in static culture under hypoxic conditions

    Yuki Kagawa, Hirotaka Miyahara, Yuri Ota, Satoshi Tsuneda

    BIOTECHNOLOGY PROGRESS   32 ( 1 ) 189 - 197  2016年01月  [査読有り]

     概要を見る

    Estimating the oxygen consumption rates (OCRs) of mammalian cells in hypoxic environments is essential for designing and developing a three-dimensional (3-D) cell culture system. However, OCR measurements under hypoxic conditions are infrequently reported in the literature. Here, we developed a system for measuring OCRs at low oxygen levels. The system injects nitrogen gas into the environment and measures the oxygen concentration by an optical oxygen microsensor that consumes no oxygen. The developed system was applied to HepG2 cells in static culture. Specifically, we measured the spatial profiles of the local dissolved oxygen concentration in the medium, then estimated the OCRs of the cells. The OCRs, and also the pericellular oxygen concentrations, decreased nonlinearly as the oxygen partial pressure in the environment decreased from 19% to 1%. The OCRs also depended on the culture period and the matrix used for coating the dish surface. Using this system, we can precisely estimate the OCRs of various cell types under environments that mimic 3-D culture conditions, contributing crucial data for an efficient 3-D culture system design. (c) 2015 American Institute of Chemical Engineers Biotechnol. Prog., 32:189-197, 2016

    DOI

  • Bacterial metabolites directly modulate farnesoid X receptor activity

    Xianqin Zhang, Toshifumi Osaka, Satoshi Tsuneda

    NUTRITION & METABOLISM   12 ( 1 ) 1 - 14  2015年11月  [査読有り]

     概要を見る

    Background: The farnesoid X receptor (FXR), a ligand-activated transcription factor belonging to the adopted orphan receptor, plays an important role in maintaining health of the liver and intestine. In this study, we identified individual bacterial strains that directly modulated the activation of intestinal FXR.
    Methods: The FXR stimulatory potential of 38 bacterial strains was determined using a stable FXR reporter system derived from intestinal epithelial cells (IEC). The induction of FXR target genes by screened FXR stimulatory bacteria was determined by real-time PCR. In addition, a high fat diet (HFD)-induced obese mouse model was used to evaluate in vivo FXR stimulatory potential of bacterial metabolites screened in this study.
    Results: A luciferase assay with the FXR reporter cell line demonstrated that the FXR-stimulatory activity of most bacterial cell samples was less than 2-fold. The culture supernatants of Bacteroides dorei and Eubacterium limosum induced FXR activity and selectively regulated FXR target expression in the FXR reporter system. Treatment with B. dorei-derived metabolites strongly induced ileal bile acid binding protein (IBABP) (8.4-fold) and organic solute transporter (OST) a (3.1-fold) compared with E. limosum-derived metabolites. Furthermore, administration of B. dorei derived metabolites showed significant reduction in body weight gain, and both two bacterial metabolites reduced liver weight in obese mice compared to PBS-treated controls. Administration of each bacterial metabolites improved in serum levels of obesity-related metabolic biochemical markers such as ALT, AST, total cholesterol, and triglyceride. Furthermore, two bacterial metabolites enhanced the Fxr gene expression in the intestine and liver, and ileal Shp gene expression tended to be increased by treatment with the metabolites derived from B. dorei.
    Conclusions: B. dorei and E. limosum secreted the bioactive substances that directly stimulate FXR in the intestinal epithelial cells. Administration of these bacterial FXR-stimulatory metabolites improves the obesity phenotype including body weight gain, liver damage, lipid metabolism in DIO mice.

    DOI

  • Selective isolation of ammonia-oxidizing bacteria from autotrophic nitrifying granules by applying cell-sorting and sub-culturing of microcolonies

    Hirotsugu Fujitani, Asami Kumagai, Norisuke Ushiki, Kengo Momiuchi, Satoshi Tsuneda

    FRONTIERS IN MICROBIOLOGY   6 ( 1159 ) 1 - 10  2015年10月  [査読有り]

     概要を見る

    Nitrification is a key process in the biogeochemical nitrogen cycle and biological wastewater treatment that consists of two stepwise reactions, ammonia oxidation by ammonia-oxidizing bacteria (AOB) or archaea followed by nitrite oxidation by nitrite-oxidizing bacteria. One of the representatives of the AOB group is Nitrosomonas mobilis species. Although a few pure strains of this species have been isolated so far, approaches to their preservation in pure culture have not been established. Here, we report isolation of novel members of the N. mobilis species from autotrophic nitrifying granules used for ammonia-rich wastewater treatment. We developed an isolation method focusing on microcolonies formation of nitrifying bacteria. Two kinds of distinctive light scattering signatures in a cell-sorting system enabled to separate microcolonies from single cells and heterogeneous aggregates within granule samples. Inoculation of a pure microcolony into 96-well microtiter plates led to successful subculturing and increased probability of isolation. Obtained strain Ms1 is cultivated in the liquid culture with relatively high ammonia or nitrite concentration, not extremely slow growing. Considering environmental clones that were closely related to N. mobilis and detected in various environments, the availability of this novel strain would facilitate to reveal this member's ecophysiology in a variety of habitats.

    DOI

  • Identification of Hydroxyanthraquinones as Novel Inhibitors of Hepatitis C Virus NS3 Helicase.

    Atsushi Furuta, Masayoshi Tsubuki, Miduki Endoh, Tatsuki Miyamoto, Junichi Tanaka, Kazi Abdus Salam, Nobuyoshi Akimitsu, Hidenori Tani, Atsuya Yamashita, Kohji Moriishi, Masamichi Nakakoshi, Yuji Sekiguchi, Satoshi Tsuneda, Naohiro Noda

    International journal of molecular sciences   16 ( 8 ) 18439 - 53  2015年08月  [査読有り]  [国際誌]

     概要を見る

    Hepatitis C virus (HCV) is an important etiological agent of severe liver diseases, including cirrhosis and hepatocellular carcinoma. The HCV genome encodes nonstructural protein 3 (NS3) helicase, which is a potential anti-HCV drug target because its enzymatic activity is essential for viral replication. Some anthracyclines are known to be NS3 helicase inhibitors and have a hydroxyanthraquinone moiety in their structures; mitoxantrone, a hydroxyanthraquinone analogue, is also known to inhibit NS3 helicase. Therefore, we hypothesized that the hydroxyanthraquinone moiety alone could also inhibit NS3 helicase. Here, we performed a structure-activity relationship study on a series of hydroxyanthraquinones by using a fluorescence-based helicase assay. Hydroxyanthraquinones inhibited NS3 helicase with IC50 values in the micromolar range. The inhibitory activity varied depending on the number and position of the phenolic hydroxyl groups, and among different hydroxyanthraquinones examined, 1,4,5,8-tetrahydroxyanthraquinone strongly inhibited NS3 helicase with an IC50 value of 6 µM. Furthermore, hypericin and sennidin A, which both have two hydroxyanthraquinone-like moieties, were found to exert even stronger inhibition with IC50 values of 3 and 0.8 µM, respectively. These results indicate that the hydroxyanthraquinone moiety can inhibit NS3 helicase and suggest that several key chemical structures are important for the inhibition.

    DOI PubMed

  • Direct Measurement of Local Dissolved Oxygen Concentration Spatial Profiles in a Cell Culture Environment

    Yuki Kagawa, Katsuhisa Matsuura, Tatsuya Shimizu, Satoshi Tsuneda

    BIOTECHNOLOGY AND BIOENGINEERING   112 ( 6 ) 1263 - 1274  2015年06月  [査読有り]

     概要を見る

    Controlling local dissolved oxygen concentration (DO) in media is critical for cell or tissue cultures. Various biomaterials and culture methods have been developed to modulate DO. Direct measurement of local DO in cultures has not been validated as a method to test DO modulation. In the present study we developed a DO measurement system equipped with a Clarktype oxygen microelectrode manipulated with I p.m precision in three-dimensional space to explore potential applications for tissue engineering. By determining the microelectrode tip position precisely against the bottom plane of culture dishes with rat or human cardiac cells in static monolayer culture, we successfully obtained spatial distributions of DO in the medium. Theoretical quantitative predictions fit the obtained data well. Based on analyses of the variance between samples, we found the data reflected "local" oxygen consumption in the vicinity of the microelectrode and the detection of temporal changes in oxygen consumption rates of cultured cells was limited by the diffusion rate of oxygen in the medium. This oxygen measuring system monitors local oxygen consumption and production with high spatial resolution, and can potentially be used with recently developed oxygen modulating biomaterials to design microenvironments and non-invasively monitor local DO dynamics during culture. (C) 2015 Wiley Periodicals, Inc.

    DOI

  • Mathematical modeling of dormant cell formation in growing biofilm

    Kotaro Chihara, Shinya Matsumoto, Yuki Kagawa, Satoshi Tsuneda

    FRONTIERS IN MICROBIOLOGY   6 ( 534 ) 1 - 8  2015年05月  [査読有り]

     概要を見る

    Understanding the dynamics of dormant cells in microbial biofilms, in which the bacteria are embedded in extracellular matrix, is important for developing successful antibiotic therapies against pathogenic bacteria. Although some of the molecular mechanisms leading to bacterial persistence have been speculated in planktonic bacterial cell, how dormant cells emerge in the biofilms of pathogenic bacteria such as Pseudomonas aeruginosa remains unclear. The present study proposes four hypotheses of dormant cell formation; stochastic process, nutrient-dependent, oxygen-dependent, and time-dependent processes. These hypotheses were implemented into a three-dimensional individual-based model of biofilm formation. Numerical simulations of the different mechanisms yielded qualitatively different spatiotemporal distributions of dormant cells in the growing biofilm. Based on these simulation results, we discuss what kinds of experimental studies are effective for discriminating dormant cell formation mechanisms in biofilms.

    DOI

  • 難培養性亜硝酸酸化細菌Nitrospiraを標的とした新規な分離培養戦略

    藤谷拓嗣, 常田 聡

    環境バイオテクノロジー学会誌   14 ( 2 ) 99 - 103  2015年03月  [招待有り]

  • Strengthening of the intestinal epithelial tight junction by Bifidobacterium bifidum.

    Chen-Yu Hsieh, Toshifumi Osaka, Eri Moriyama, Yasuhiro Date, Jun Kikuchi, Satoshi Tsuneda

    Physiological reports   3 ( 3 ) e12327  2015年03月  [査読有り]  [国際誌]

     概要を見る

    Epithelial barrier dysfunction has been implicated as one of the major contributors to the pathogenesis of inflammatory bowel disease. The increase in intestinal permeability allows the translocation of luminal antigens across the intestinal epithelium, leading to the exacerbation of colitis. Thus, therapies targeted at specifically restoring tight junction barrier function are thought to have great potential as an alternative or supplement to immunology-based therapies. In this study, we screened Bifidobacterium, Enterococcus, and Lactobacillus species for beneficial microbes to strengthen the intestinal epithelial barrier, using the human intestinal epithelial cell line (Caco-2) in an in vitro assay. Some Bifidobacterium and Lactobacillus species prevented epithelial barrier disruption induced by TNF-α, as assessed by measuring the transepithelial electrical resistance (TER). Furthermore, live Bifidobacterium species promoted wound repair in Caco-2 cell monolayers treated with TNF-α for 48 h. Time course (1)H-NMR-based metabonomics of the culture supernatant revealed markedly enhanced production of acetate after 12 hours of coincubation of B. bifidum and Caco-2. An increase in TER was observed by the administration of acetate to TNF-α-treated Caco-2 monolayers. Interestingly, acetate-induced TER-enhancing effect in the coculture of B. bifidum and Caco-2 cells depends on the differentiation stage of the intestinal epithelial cells. These results suggest that Bifidobacterium species enhance intestinal epithelial barrier function via metabolites such as acetate.

    DOI PubMed

  • Melting Curve Analysis after T Allele Enrichment (MelcaTle) as a Highly Sensitive and Reliable Method for Detecting the JAK2V617F Mutation

    Soji Morishita, Kochi Takahashi, Marito Araki, Yumi Hironaka, Yoshitaka Sunami, Yoko Edahiro, Miyuki Tsutsui, Akimichi Ohsaka, Satoshi Tsuneda, Norio Komatsu

    PLOS ONE   10 ( 3 ) e0122003  2015年03月  [査読有り]

     概要を見る

    Detection of the JAK2V617F mutation is essential for diagnosing patients with classical myeloproliferative neoplasms (MPNs). However, detection of the low-frequency JAK2V617F mutation is a challenging task due to the necessity of discriminating between true-positive and false-positive results. Here, we have developed a highly sensitive and accurate assay for the detection of JAK2V617F and named it melting curve analysis after T allele enrichment (MelcaTle). MelcaTle comprises three steps: 1) two cycles of JAK2V617F allele enrichment by PCR amplification followed by BsaXI digestion, 2) selective amplification of the JAK2V617F allele in the presence of a bridged nucleic acid (BNA) probe, and 3) a melting curve assay using a BODIPY-FL-labeled oligonucleotide. Using this assay, we successfully detected nearly a single copy of the JAK2V617F allele, without false-positive signals, using 10 ng of genomic DNA standard. Furthermore, MelcaTle showed no positive signals in 90 assays screening healthy individuals for JAK2V617F. When applying MelcaTle to 27 patients who were initially classified as JAK2V617F-positive on the basis of allele-specific PCR analysis and were thus suspected as having MPNs, we found that two of the patients were actually JAK2V617F-negative. A more careful clinical data analysis revealed that these two patients had developed transient erythrocytosis of unknown etiology but not polycythemia vera, a subtype of MPNs. These findings indicate that the newly developed MelcaTle assay should markedly improve the diagnosis of JAK2V617F-positive MPNs.

    DOI

  • A fluorescence-based screening assay for identification of hepatitis C virus NS3 helicase inhibitors and characterization of their inhibitory mechanism.

    Furuta A, Salam KA, Tani H, Tsuneda S, Sekiguchi Y, Akimitsu N, Noda N

    Methods in molecular biology (Clifton, N.J.)   1259   211 - 28  2015年  [査読有り]  [国際誌]

    DOI PubMed

  • Modeling the Nutrient Removal Process in Aerobic Granular Sludge System by Coupling the Reactor- and Granule-Scale Models

    Y. Kagawa, J. Tahata, N. Kishida, S. Matsumoto, C. Picioreanu, M. C. M. van Loosdrecht, S. Tsuneda

    BIOTECHNOLOGY AND BIOENGINEERING   112 ( 1 ) 53 - 64  2015年01月  [査読有り]

     概要を見る

    We developed a model for nutrient removal in an aerobic granular sludge system. This model can quantitatively describe the start-up of the system by coupling a model for studying the population dynamics of the granules in the reactor (reactor-scale model) and a model for studying the microbial community structure in the granules (granule-scale model). The reactor-scale model is used for simulation for 10 days from the start, during which the granule size is relatively small; the granule-scale model is used after Day 10. The present approach proposes the output data of the reactor-scale model after 10 days as initial conditions for the granule-scale model. The constructed model satisfactorily describes experimental data in various spatial and temporal scales, which were obtained in this study by performing the anaerobic-aerobic-anoxic cycles using a sequencing batch reactor. Simulations using this model quantitatively predicted that the stability of nutrient removal process depended largely on the dissolved oxygen (DO) concentration, and the DO setpoint adaptation could improve the nutrient removal performance. (C) 2014 Wiley Periodicals, Inc.

    DOI

  • Phosphorylated 5-ethynyl-2′-deoxyuridine for advanced DNA labeling

    Seo, Siyoong, Seo, Siyoong, Onizuka, Kazumitsu, Nishioka, Chieko, Takahashi, Eiki, Tsuneda, Satoshi, Abe, Hiroshi, Abe, Hiroshi, Ito, Yoshihiro, Ito, Yoshihiro, Ito, Yoshihiro

    Organic and Biomolecular Chemistry   13 ( 15 ) 4589 - 4595  2015年  [査読有り]

     概要を見る

    © 2015 The Royal Society of Chemistry. The representative DNA-labeling agent 5-ethynyl-2′-deoxyuridine (EdU) was chemically modified to improve its function. Chemical monophosphorylation was expected to enhance the efficiency of the substrate in DNA polymerization by circumventing the enzymatic monophosphorylation step that consumes energy. In addition, to enhance cell permeability, the phosphates were protected with bis-pivaloyloxymethyl that is stable in buffer and plasma, and degradable inside various cell types. The phosphorylated EdU (PEdU) was less toxic than EdU, and had the same or a slightly higher DNA-labeling ability in vitro. PEdU was also successfully applied to DNA labeling in vivo. In conclusion, PEdU can be used as a less toxic DNA-labeling agent for studies that require long-term cell survival or very sensitive cell lines.

    DOI

  • Isolation of sublineage I Nitrospira by a novel cultivation strategy

    Hirotsugu Fujitani, Norisuke Ushiki, Satoshi Tsuneda, Yoshiteru Aoi

    ENVIRONMENTAL MICROBIOLOGY   16 ( 10 ) 3030 - 3040  2014年10月  [査読有り]

     概要を見る

    Nitrification is an important process in the biogeochemical nitrogen cycle and is widely exploited in biological wastewater treatment. Recently, Nitrospira has been recognized as the numerically dominant nitrite-oxidizing bacterial genus and is primarily responsible for the second step of aerobic nitrification. Nevertheless, the physiological properties of Nitrospira remain poorly understood because the organisms are difficult to isolate and culture. Here, we report a novel cultivation strategy for obtaining members of the Nitrospira sublineage I in pure culture. The method combines: (i) selective enrichment of Nitrospira using a continuous feeding reactor and (ii) purification followed by sub-cultivation via a cell sorting system by focusing on the unique characteristics of Nitrospira forming spherical micro-colonies. This strategy is potentially applicable to other uncultured or unisolated Nitrospira and could accelerate the physiological and biochemical understandings of this important group of organisms.

    DOI

  • Phosphorylated gelatin to enhance cell adhesion to titanium

    Shin-Hye Park, Liping Zhu, Seiichi Tada, Sei Obuse, Yasuhiro Yoshida, Mariko Nakamura, Tae Il Son, Satoshi Tsuneda, Yoshihiro Ito

    POLYMER INTERNATIONAL   63 ( 9 ) 1616 - 1619  2014年09月  [査読有り]

     概要を見る

    Phosphorylated gelatin was prepared for surface modification of titanium to enhance cell attachment. The modified gelatin was synthesized by coupling gelatin with phosphonobutyric acid with water-soluble carbodiimide. Circular dichroism revealed no significant change in the gelatin as a result of phosphorylation. The binding behavior of phosphorylated gelatin on the titanium surface was observed by quartz crystal microbalance. The modified titanium surface was analyzed by measuring the water contact angle. Enhancement of the attachment of osteoblast cells MC-3T3L1 was observed on the phosphorylated-gelatin-modified titanium. Phosphorylation of gelatin was effective for preparation of a cell-adhesive titanium surface. (C) 2013 Society of Chemical Industry

    DOI

  • Mathematical modelling of spatio-temporal cell dynamics in colonic crypts following irradiation

    T. Murano, Y. Kagawa, S. Tsuneda

    CELL PROLIFERATION   47 ( 4 ) 347 - 355  2014年08月  [査読有り]

     概要を見る

    Objectives: Modelling the apoptotic process is essential for simulating and understanding tumour growth, as most tumour tissues carry mutations in apoptotic signalling pathways. Thus here, we have aimed to construct a mathematical model of colonic crypts that explicitly incorporates the apoptotic mechanism.
    Methods: A murine colonic crypt was described as being a two-dimensional rectangular surface model. In this system, three types of cells with different proliferating and differentiating potentials migrate. Apoptosis was described as a process activated by irradiation that progresses in a stepwise manner. Parameter values in the model were determined to be consistent with experimental data for changes in the apoptotic cell ratio within murine transverse colonic crypts following irradiation.
    Results: First, we constructed a model reproducing cell proliferation dynamics in normal murine colonic crypts; next, we applied the apoptotic mechanism to this model. As a result, we succeeded in simultaneous reproduction of both spatial and temporal changes in distribution of apoptotic cells in murine colonic crypts by determining parameter values in numerical simulations. Through this adjustment process, we were able to predict that stem cells and transit amplifying (TA) cells in each generation must react distinctly from each other, to apoptosis-inducing stimuli.
    Conclusions: We constructed a mathematical model with which we could quantitatively describe cell proliferative and apoptotic dynamics in a murine colonic crypt. Using this model, we were able to make novel predictions that sensitivity to apoptosis-inducing stimuli is dependent on cell type.

    DOI

  • Detection of MPLW515L/K Mutations and Determination of Allele Frequencies with a Single-Tube PCR Assay

    Hiraku Takei, Soji Morishita, Marito Araki, Yoko Edahiro, Yoshitaka Sunami, Yumi Hironaka, Naohiro Noda, Yuji Sekiguchi, Satoshi Tsuneda, Akimichi Ohsaka, Norio Komatsu

    PLOS ONE   9 ( 8 ) e104958  2014年08月  [査読有り]

     概要を見る

    A gain-of-function mutation in the myeloproliferative leukemia virus (MPL) gene, which encodes the thrombopoietin receptor, has been identified in patients with essential thrombocythemia and primary myelofibrosis, subgroups of classic myeloproliferative neoplasms (MPNs). The presence of MPL gene mutations is a critical diagnostic criterion for these diseases. Here, we developed a rapid, simple, and cost-effective method of detecting two major MPL mutations, MPLW515L/K, in a single PCR assay; we termed this method DARMS (dual amplification refractory mutation system)-PCR. DARMS-PCR is designed to produce three different PCR products corresponding to MPLW515L, MPLW515K, and all MPL alleles. The amplicons are later detected and quantified using a capillary sequencer to determine the relative frequencies of the mutant and wild-type alleles. Applying DARMS-PCR to human specimens, we successfully identified MPL mutations in MPN patients, with the exception of patients bearing mutant allele frequencies below the detection limit (5%) of this method. The MPL mutant allele frequencies determined using DARMS-PCR correlated strongly with the values determined using deep sequencing. Thus, we demonstrated the potential of DARMS-PCR to detect MPL mutations and determine the allele frequencies in a timely and cost-effective manner.

    DOI

  • JAK2V617F mutation status and allele burden in classical Ph-negative myeloproliferative neoplasms in Japan

    Yoko Edahiro, Soji Morishita, Kochi Takahashi, Yumi Hironaka, Yuriko Yahata, Yoshitaka Sunami, Shuichi Shirane, Miyuki Tsutsui, Masaaki Noguchi, Michiaki Koike, Kiyotoshi Imai, Keita Kirito, Naohiro Noda, Yuji Sekiguchi, Satoshi Tsuneda, Akimichi Ohsaka, Marito Araki, Norio Komatsu

    INTERNATIONAL JOURNAL OF HEMATOLOGY   99 ( 5 ) 625 - 634  2014年05月  [査読有り]

     概要を見る

    JAK2V617F, a gain-of-function mutation in the tyrosine kinase JAK2, is frequently detected in classical myeloproliferative neoplasms (MPNs). In the present study, we determined the JAK2V617F allele burden in Japanese MPN patients using alternately binding probe competitive-polymerase chain reaction, a highly quantitative method recently developed by our group. Although we observed strong similarities in terms of epidemiological parameters associated with the JAK2V617F allele burden between our cohort and others, we found a higher JAK2V617F allele burden in Japanese polycythemia vera (PV) patients and lower frequencies of thrombosis in Japanese MPN patients compared with previous reports. In addition, despite the presence of high red blood cell counts, some patients bearing the JAK2V617F mutation were not diagnosed as PV, as their hemoglobin values were lower than the WHO PV criterion. In these patients, the JAK2V617F allele burden was strikingly similar to that in PV patients fulfilling the 2008 WHO criteria, suggesting that these patients can be classified as PV. Although isotopic measurement of red cell mass (RCM) is required for definitive diagnosis of PV, our data suggest that precise measurement of the JAK2V617F allele burden may improve the diagnosis of PV when RCM has not been determined.

    DOI

  • Cholesterol sulfate as a potential inhibitor of hepatitis C virus NS3 helicase

    Atsushi Furuta, Kazi Abdus Salam, Nobuyoshi Akimitsu, Junichi Tanaka, Hidenori Tani, Atsuya Yamashita, Kohji Moriishi, Masamichi Nakakoshi, Masayoshi Tsubuki, Yuji Sekiguchi, Satoshi Tsuneda, Naohiro Noda

    JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY   29 ( 2 ) 223 - 229  2014年04月  [査読有り]

     概要を見る

    Hepatitis C virus nonstructural protein 3 (NS3) helicase is a promising target for developing new therapeutics. In this study, we identified cholesterol sulfate (CS) as a novel NS3 helicase inhibitor (IC50 = 1.7 +/- 0.2 mu M with a Hill coefficient of 3.9) by screening the extracts from marine organisms. The lack of the sulfate group, sterol structure or alkyl side chain of CS diminished the inhibition, suggesting that an anion binding and hydrophobic region in NS3 may be a target site of CS. It was further found that CS partly inhibits NS3-RNA binding activity, but exerted no or less inhibition against ATPase and serine protease activities. Moreover, we demonstrated that CS probably does not bind to RNA. Our findings suggest that CS may inhibit NS3 helicase not by abolishing the other NS3 activities but by inducing conformational changes via interaction with possible allosteric sites of NS3.

    DOI

  • PBDE: Structure-Activity Studies for the Inhibition of Hepatitis C Virus NS3 Helicase

    Kazi Abdus Salam, Atsushi Furuta, Naohiro Noda, Satoshi Tsuneda, Yuji Sekiguchi, Atsuya Yamashita, Kohji Moriishi, Masamichi Nakakoshi, Hidenori Tani, Sona Rani Roy, Junichi Tanaka, Masayoshi Tsubuki, Nobuyoshi Akimitsu

    MOLECULES   19 ( 4 ) 4006 - 4020  2014年04月  [査読有り]

     概要を見る

    The helicase portion of the hepatitis C virus nonstructural protein 3 (NS3) is considered one of the most validated targets for developing direct acting antiviral agents. We isolated polybrominated diphenyl ether (PBDE) 1 from a marine sponge as an NS3 helicase inhibitor. In this study, we evaluated the inhibitory effects of PBDE (1) on the essential activities of NS3 protein such as RNA helicase, ATPase, and RNA binding activities. The structure-activity relationship analysis of PBDE (1) against the HCV ATPase revealed that the biphenyl ring, bromine, and phenolic hydroxyl group on the benzene backbone might be a basic scaffold for the inhibitory potency.

    DOI

  • Modeling of stem cell dynamics in human colonic crypts in silico

    Yuki Kagawa, Noriko Horita, Hideki Taniguchi, Satoshi Tsuneda

    JOURNAL OF GASTROENTEROLOGY   49 ( 2 ) 263 - 269  2014年02月  [査読有り]

     概要を見る

    Several possible scenarios of cellular dynamics in human colonic crypts have been inferred from transgenic animal experiments. However, because of the discrepancy in size and physiology between humans and animals, quantitative predictions of tissue renewal and cancer development are difficult to execute.
    A two-dimensional individual based model was developed for the first time to predict cellular dynamics in human colonic crypts. A simple scenario, in which stem cells were not fixed positionally, divide symmetrically and asymmetrically in a stochastic fashion in the lower part of the crypt, was proposed and implemented in the developed model. Numerical simulations of the model were executed in silico.
    By comparing the results of computational simulations with available experimental data, the presented scenario was consistent with various experimental evidence. Using this scenario, we simulated and visualized monoclonal conversion in the human colonic crypt. We also predicted that the propensity for monoclonal expansion of a mutant cell was largely dependent on the phenotype, the cell type, the position and the state of the crypt.
    Using the computational framework developed in this study, model users can verify possible scenarios of stem cell dynamics occurring in human colonic crypts and quantitatively predict cell behavior. Its applicability in scenario verification and predictability makes it a valuable tool for elucidation of stem cell dynamics in human colonic crypts.

    DOI

  • Identification and Biochemical Characterization of Halisulfate 3 and Suvanine as Novel Inhibitors of Hepatitis C Virus NS3 Helicase from a Marine Sponge

    Atsushi Furuta, Kazi Abdus Salam, Idam Hermawan, Nobuyoshi Akimitsu, Junichi Tanaka, Hidenori Tani, Atsuya Yamashita, Kohji Moriishi, Masamichi Nakakoshi, Masayoshi Tsubuki, Poh Wee Peng, Youichi Suzuki, Naoki Yamamoto, Yuji Sekiguchi, Satoshi Tsuneda, Naohiro Noda

    MARINE DRUGS   12 ( 1 ) 462 - 476  2014年01月  [査読有り]

     概要を見る

    Hepatitis C virus (HCV) is an important etiological agent that is responsible for the development of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. HCV nonstructural protein 3 (NS3) helicase is a possible target for novel drug development due to its essential role in viral replication. In this study, we identified halisulfate 3 (hal3) and suvanine as novel NS3 helicase inhibitors, with IC50 values of 4 and 3 mu M, respectively, from a marine sponge by screening extracts of marine organisms. Both hal3 and suvanine inhibited the ATPase, RNA binding, and serine protease activities of NS3 helicase with IC50 values of 8, 8, and 14 mu M, and 7, 3, and 34 mu M, respectively. However, the dengue virus (DENV) NS3 helicase, which shares a catalytic core (consisting mainly of ATPase and RNA binding sites) with HCV NS3 helicase, was not inhibited by hal3 and suvanine, even at concentrations of 100 mu M. Therefore, we conclude that hal3 and suvanine specifically inhibit HCV NS3 helicase via an interaction with an allosteric site in NS3 rather than binding to the catalytic core. This led to the inhibition of all NS3 activities, presumably by inducing conformational changes.

    DOI

  • Applicability of a Sequencing Batch Membrane Biofilm Reactor for Simultaneous Nitrogen and Phosphorus Removal from Low C/N Ratio Wastewater

    A. Terada, J. ito, S. Matsumoto, S. Tsuneda

    J. Water Environ. Technol.   11 ( 6 ) 488 - 496  2013年12月

    DOI

  • Complete autotrophic denitrification in a single reactor using nitritation and anammox gel carriers

    Kazuichi Isaka, Yuya Kimura, Tomoko Yamamoto, Toshifumi Osaka, Satoshi Tsuneda

    BIORESOURCE TECHNOLOGY   147   96 - 101  2013年11月  [査読有り]

     概要を見る

    A novel aerobic denitrification reactor, aerobic denitrification using nitrifying and anoxic ammonium-oxidizing (anammox) bacteria immobilized on gel carriers in a single stage (AIGES), was developed. Two types of gel carriers, a nitritation gel carrier and an anammox gel carrier, were installed in single reactor, and the denitrification performance of simultaneous nitritation and anammox was evaluated. The denitrification performance increased gradually with increased aeration rate, reaching a denitrification rate of 1.4 kg N m(-3) d(-1) 2 weeks after the nitritation and anammox gel carriers were mixed. A high average denitrification efficiency of 82% was confirmed. Stable aerobic denitrification performance was observed for more than half a year. In the startup period of AIGES operation, ammonia-oxidizing bacteria were shown by fluorescence in situ hybridization analysis to grow on the surface layer of anammox gel cubes. These results indicated that anammox gel carriers promptly adapted to an aerobic environment by altering the microbial ecosystem. (C) 2013 Elsevier Ltd. All rights reserved.

    DOI

  • Psammaplin A inhibits hepatitis C virus NS3 helicase.

    Kazi Abdus Salam, Atsushi Furuta, Naohiro Noda, Satoshi Tsuneda, Yuji Sekiguchi, Atsuya Yamashita, Kohji Moriishi, Masamichi Nakakoshi, Masayoshi Tsubuki, Hidenori Tani, Junichi Tanaka, Nobuyoshi Akimitsu

    Journal of natural medicines   67 ( 4 ) 765 - 72  2013年10月  [国内誌]

     概要を見る

    Hepatitis C virus (HCV) is the causative agent of hepatitis C, a chronic infectious disease that can lead to development of hepatocellular carcinoma. The NS3 nucleoside triphosphatase (NTPase)/helicase has an essential role in HCV replication, and is therefore an attractive target for direct-acting antiviral strategies. In this study, we employed high-throughput screening using a photo-induced electron transfer (PET) system to identify an inhibitor of NS3 helicase from marine organism extracts. We successfully identified psammaplin A as a novel NS3 inhibitor. The dose-response relationship clearly demonstrates the inhibition of NS3 RNA helicase and ATPase activities by psammaplin A, with IC₅₀ values of 17 and 32 μM, respectively. Psammaplin A has no influence on the apparent Km value (0.4 mM) of NS3 ATPase activity, and acts as a non-competitive inhibitor. Additionally, it inhibits the binding of NS3 to single-stranded RNA in a dose-dependent manner. Furthermore, psammaplin A shows an inhibitory effect on viral replication, with EC₅₀ values of 6.1 and 6.3 μM in subgenomic replicon cells derived from genotypes 1b and 2a, respectively. We postulate that psammaplin A is a potential anti-viral agent through the inhibition of ATPase, RNA binding and helicase activities of NS3.

    DOI PubMed

  • Isolation of Nitrospira belonging to Sublineage II from a Wastewater Treatment Plant

    Norisuke Ushiki, Hirotsugu Fujitani, Yoshiteru Aoi, Satoshi Tsuneda

    MICROBES AND ENVIRONMENTS   28 ( 3 ) 346 - 353  2013年09月  [査読有り]

     概要を見る

    Nitrite oxidation is a key step in nitrogen removal in biological wastewater treatment plants. Recently, two phylogenetically different Nitrospira (sublineages I and II) have been recognized as the numerically dominant nitrite-oxidizing bacteria in wastewater treatment plants. However, Nitrospira sublineage II inhabiting activated sludge was not isolated and its detailed properties were unclear. In this study, we developed a new method for the isolation of Nitrospira forming micro-colonies using a cell sorter. We obtained a novel pure strain "Nitrospira japonica" from the activated sludge. Subsequently, phylogenetic and physiological analyses revealed that Nitrospira japonica belongs to sublineage II and grew in medium containing formate. This method has the potential to isolate other uncultured microorganisms forming micro-colonies.

    DOI

  • Selective enrichment of two different types of Nitrospira-like nitrite-oxidizing bacteria from a wastewater treatment plant

    Hirotsugu Fujitani, Yoshiteru Aoi, Satoshi Tsuneda

    Microbes and Environments   28 ( 2 ) 236 - 243  2013年06月

     概要を見る

    Nitrification is an important step in nitrogen removal in biological wastewater treatment processes. Recently, Nitrospira have been recognized as the numerically dominant nitrite-oxidizing bacterial genus primarily responsible for the second step of aerobic nitrification
    however, Nitrospira usually resist cultivation under laboratory conditions and only one species enriched from activated sludge has been described. In this study, a novel enrichment method for Nitrospira was successfully developed using continuous feeding bioreactors. By controlling nitrite concentrations strictly in the bioreactor at low levels below 10 mg-N L-1, coexisting members of sublineages I and II of the genus Nitrospira were enriched selectively. The maximum ratios of sublineages I and II to total microbial cells achieved 88.3% and 53.8%, respectively. This enrichment method is potentially applicable to other uncultured Nitrospira.

    DOI PubMed

  • Detection of pre-mRNA splicing in vitro by an RNA-templated fluorogenic reaction

    Yasutsugu Tamura, Kazuhiro Furukawa, Rei Yoshimoto, Yuto Kawai, Minoru Yoshida, Satoshi Tsuneda, Yoshihiro Ito, Hiroshi Abe

    BIOORGANIC & MEDICINAL CHEMISTRY LETTERS   22 ( 23 ) 7248 - 7251  2012年12月  [査読有り]

     概要を見る

    RNA splicing is an important target for basic research of disease mechanisms and for drug discovery. Here, we report a new method for analysis of the in vitro RNA splicing process that produces fluorescence using a reduction-triggered fluorescence (RETF) probe. The fluorescence signal is produced only when the two probes bind side-by-side with a specific RNA target. Precursor messenger RNA and mature messenger RNA originating from the chicken delta-crystallin (CDC) gene were successfully discriminated in solution using an RETF probe with the assistance of helper oligonucleotide strands. Also, we successfully applied RETF probes to the detection of emerging mature mRNA in an in vitro splicing process. (C) 2012 Elsevier Ltd. All rights reserved.

    DOI

  • Inhibition of Both Protease and Helicase Activities of Hepatitis C Virus NS3 by an Ethyl Acetate Extract of Marine Sponge Amphimedon sp.

    Yuusuke Fujimoto, Kazi Abdus Salam, Atsushi Furuta, Yasuyoshi Matsuda, Osamu Fujita, Hidenori Tani, Masanori Ikeda, Nobuyuki Kato, Naoya Sakamoto, Shinya Maekawa, Nobuyuki Enomoto, Nicole J. de Voogd, Masamichi Nakakoshi, Masayoshi Tsubuki, Yuji Sekiguchi, Satoshi Tsuneda, Nobuyoshi Akimitsu, Naohiro Noda, Atsuya Yamashita, Junichi Tanaka, Kohji Moriishi

    PLOS ONE   7 ( 11 ) e48685  2012年11月  [査読有り]

     概要を見る

    Combination therapy with ribavirin, interferon, and viral protease inhibitors could be expected to elicit a high level of sustained virologic response in patients infected with hepatitis C virus (HCV). However, several severe side effects of this combination therapy have been encountered in clinical trials. In order to develop more effective and safer anti-HCV compounds, we employed the replicon systems derived from several strains of HCV to screen 84 extracts from 54 organisms that were gathered from the sea surrounding Okinawa Prefecture, Japan. The ethyl acetate-soluble extract that was prepared from marine sponge Amphimedon sp. showed the highest inhibitory effect on viral replication, with EC50 values of 1.5 and 24.9 mu g/ml in sub-genomic replicon cell lines derived from genotypes 1b and 2a, respectively. But the extract had no effect on interferon-inducing signaling or cytotoxicity. Treatment with the extract inhibited virus production by 30% relative to the control in the JFH1-Huh7 cell culture system. The in vitro enzymological assays revealed that treatment with the extract suppressed both helicase and protease activities of NS3 with IC50 values of 18.9 and 10.9 mu g/ml, respectively. Treatment with the extract of Amphimedon sp. inhibited RNA-binding ability but not ATPase activity. These results suggest that the novel compound(s) included in Amphimedon sp. can target the protease and helicase activities of HCV NS3.

    DOI

  • 複合微生物系の挙動を表現可能な数理モデル

    松本慎也, 加川友己, 常田聡

    化学工学   76 ( 11 ) 671 - 673  2012年11月

  • Temperature dependence for anammox bacteria enriched from freshwater sediments

    Toshifumi Osaka, Yuya Kimura, Yosuke Otsubo, Yuichi Suwa, Satoshi Tsuneda, Kazuichi Isaka

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   114 ( 4 ) 429 - 434  2012年10月  [査読有り]

     概要を見る

    The anoxic ammonium oxidation (anammox) process has been regarded as an attractive alternative process to treat wastewater containing high ammonium concentrations. By the implementation of anammox process at moderately low temperatures (&lt;25 degrees C), the anammox process will be applied to more various industrial wastewater treatments. In this study, we established enrichment cultures of anammox bacteria from freshwater sediments by using an up-flow column reactor equipped with porous polyester nonwoven fabric at moderately low temperatures. Their nitrogen conversion rates reached 0.07-0.26 kg-N/m(3)/d. Phylogenetic analysis based on 16S rRNA gene from enrichment cultures revealed the presence of various anammox bacteria affiliated with unknown anammox bacteria as well as known anammox candidates, i.e., Candidatus Kuenenia stuttgartiensis and Candidatus Brocadia fulgida, Candidatus Scalindua wagneri. Anammox bacterial populations were influenced by enrichment conditions, i.e., seed sediments and temperature. (C) 2012, The Society for Biotechnology, Japan. All rights reserved.

    DOI

  • High-rate denitrification using polyethylene glycol gel carriers entrapping heterotrophic denitrifying bacteria

    Kazuichi Isaka, Yuya Kimura, Toshifumi Osaka, Satoshi Tsuneda

    WATER RESEARCH   46 ( 16 ) 4941 - 4948  2012年10月  [査読有り]

     概要を見る

    This study evaluated the nitrogen removal performance of polyethylene glycol (PEG) gel carriers containing entrapped heterotrophic denitrifying bacteria. A laboratory-scale denitrification reactor was operated for treatment of synthetic nitrate wastewater. The nitrogen removal activity gradually increased in continuous feed experiments, reaching 4.4 kg N m(-1) d(-1) on day 16 (30 degrees C). A maximum nitrogen removal rate of 5.1 kg N m(-3) d(-1) was observed. A high nitrogen removal efficiency of 92% on average was observed at a high loading rate. In batch experiments, the denitrifying gel carriers were characterized by temperature. Nitrate and total nitrogen removal activities both increased with increasing temperature, reaching a maximum at 37 and 43 degrees C, respectively. Apparent activation energies for nitrate and nitrite reduction were 52.1 and 71.9 kJ mol(-1), respectively. Clone library analysis performed on the basis of the 16S rRNA gene revealed that Hyphomicrobium was mainly involved in denitrification in the methanol-fed denitrification reactors. (C) 2012 Elsevier Ltd. All rights reserved.

    DOI

  • 還元反応を引き金とするoff/on型蛍光プローブを用いたRNA検出法の開発

    阿部洋, 柴田綾, 古川和寛, 常田聡, 伊藤嘉浩

    化学と生物   50 ( 7 ) 540 - 544  2012年07月

  • The effect of surface charge property on Escherichia coli initial adhesion and subsequent biofilm formation

    Akihiko Terada, Keisuke Okuyama, Megumi Nishikawa, Satoshi Tsuneda, Masaaki Hosomi

    BIOTECHNOLOGY AND BIOENGINEERING   109 ( 7 ) 1745 - 1754  2012年07月  [査読有り]

     概要を見る

    Polyethylene (PE) sheets were modified by radiation-induced graft polymerization (RIGP) of an epoxy-group containing monomer glycidyl methacrylate (GMA). The epoxy group of GMA was opened by introducing sodium sulfite (SS) and diethylamine (DEA) as representatives of negatively and positively charged functional groups, respectively. These modified surfaces by RIGP, termed GMA, SS, and DEA sheets, were investigated to elucidate their effects on initial adhesion and subsequent biofilm formation of Escherichia coli. Initial adhesion test revealed that E. coli density and viability were governed by sheet surface electrostatic property: E. coli cell density on the DEA sheet was 23 times higher than that on the SS sheet after 8?h incubation. The viability of E. coli cells dramatically decreased after contact with the DEA sheet, but remained high on the SS sheet. E. coli biofilm structure on the DEA sheet was dense, homogeneous, and uniform, with biomass higher than that of the GMA and SS sheets by factors of 14.0 and 37.5, respectively. On the contrary, biofilm structure on the SS sheet was sparse, heterogeneous, and mushroom-shaped. More than 40% of E. coli biofilm on the DEA sheet was retained under a high liquid shear force condition (5,000?s-1), whereas 97% and 100% of biofilms on the GMA and SS sheets were sloughed, indicating that E. coli biofilm robustness depends on surface charge property of the substratum. This suggests that substratum surface fabrication by RIGP may enhance or suppress biofilm formation, a finding with potentially important practical implications. Biotechnol. Bioeng. 2012; 109:17451754. (C) 2012 Wiley Periodicals, Inc.

    DOI

  • Challenge for Formation of Aerobic Granular Sludge in a Continuous-Flow Reactor

    N. Kishida, R. Totsuka, S. Tsuneda

    J. Water Environ. Technol.   10 ( 2 ) 79 - 86  2012年06月

    DOI

  • Inhibition of Hepatitis C Virus Replication and Viral Helicase by Ethyl Acetate Extract of the Marine Feather Star Alloeocomatella polycladia

    Atsuya Yamashita, Kazi Abdus Salam, Atsushi Furuta, Yasuyoshi Matsuda, Osamu Fujita, Hidenori Tani, Yoshihisa Fujita, Yuusuke Fujimoto, Masanori Ikeda, Nobuyuki Kato, Naoya Sakamoto, Shinya Maekawa, Nobuyuki Enomoto, Masamichi Nakakoshi, Masayoshi Tsubuki, Yuji Sekiguchi, Satoshi Tsuneda, Nobuyoshi Akimitsu, Naohiro Noda, Junichi Tanaka, Kohji Moriishi

    MARINE DRUGS   10 ( 4 ) 744 - 761  2012年04月  [査読有り]

     概要を見る

    Hepatitis C virus (HCV) is a causative agent of acute and chronic hepatitis, leading to the development of hepatic cirrhosis and hepatocellular carcinoma. We prepared extracts from 61 marine organisms and screened them by an in vitro fluorescence assay targeting the viral helicase (NS3), which plays an important role in HCV replication, to identify effective candidates for anti-HCV agents. An ethyl acetate-soluble fraction of the feather star Alloeocomatella polycladia exhibited the strongest inhibition of NS3 helicase activity, with an IC50 of 11.7 mu g/mL. The extract of A. polycladia inhibited interaction between NS3 and RNA but not ATPase of NS3. Furthermore, the replication of the replicons derived from three HCV strains of genotype 1b in cultured cells was suppressed by the extract with an EC50 value of 23 to 44 mu g/mL, which is similar to the IC50 value of the NS3 helicase assay. The extract did not induce interferon or inhibit cell growth. These results suggest that the unknown compound(s) included in A. polycladia can inhibit HCV replication by suppressing the helicase activity of HCV NS3. This study may present a new approach toward the development of a novel therapy for chronic hepatitis C.

    DOI

  • システム論的アプローチによる複合微生物系の解析と制御

    松本慎也, 常田 聡

    生物工学   90 ( 4 ) 160 - 164  2012年04月

  • Inhibition of Hepatitis C Virus NS3 Helicase by Manoalide

    Kazi Abdus Salam, Atsushi Furuta, Naohiro Noda, Satoshi Tsuneda, Yuji Sekiguchi, Atsuya Yamashita, Kohji Moriishi, Masamichi Nakakoshi, Masayoshi Tsubuki, Hidenori Tani, Junichi Tanaka, Nobuyoshi Akimitsu

    JOURNAL OF NATURAL PRODUCTS   75 ( 4 ) 650 - 654  2012年04月  [査読有り]

     概要を見る

    The hepatitis C virus (HCV) causes one of the most prevalent chronic infectious diseases in the world hepatitis C, which ultimately develops into liver cancer through cirrhosis. The NS3 protein of HCV possesses nucleoside triphosphatase (NTPase) and RNA helicase activities. As both activities are essential for viral replication, NS3 is proposed as an ideal target for antiviral drug development. In this study, we identified manoalide (1) from marine sponge extracts as an RNA helicase inhibitor using a high-throughput screening photoinduced electron transfer (PET) system that we previously developed. Compound 1 inhibits the RNA helicase and ATPase activities of NS3 in a dose dependent manner, with IC50 values of 15 and 70 mu M, respectively. Biochemical kinetic analysis demonstrated that 1 does not affect the apparent K-m stranded RNA was inhibited by 1. Monoalide (1) also has the ability to inhibit the ATPase activity of human DHX36/RHAU, a putative RNA helicase. Taken together, we conclude that 1 inhibits the ATPase, RNA binding, and helicase activities of NS3 by targeting the helicase core domain conserved in both HCV NS3 and DHX36/RHAU.

    DOI

  • Formation of Nitrifying Granules Using a Continuous Stirred Tank Reactor

    N. Kishida, Y. Yamashita, S. Tsuneda

    J. Water Environ. Technol.   10 ( 1 ) 47 - 55  2012年03月

    DOI

  • Quantitative detection of Cryptosporidium oocyst in water source based on 18S rRNA by alternately binding probe competitive reverse transcription polymerase chain reaction (ABC-RT-PCR)

    Naohiro Kishida, Ryo Miyata, Atsushi Furuta, Shinji Izumiyama, Satoshi Tsuneda, Yuji Sekiguchi, Naohiro Noda, Michihiro Akiba

    WATER RESEARCH   46 ( 1 ) 187 - 194  2012年01月  [査読有り]

     概要を見る

    We describe an assay for simple and cost-effective quantification of Cryptosporidium oocysts in water samples using a recently developed quantification method named alternately binding probe competitive PCR (ABC-PCR). The assay is based on the detection of 18S rRNA specific for Cryptosporidium oocysts. The standard curve of the ABC-PCR assay had a good fitting to a rectangular hyperbola with a correlation coefficient (R) of 0.9997. Concentrations of Cryptosporidium oocysts in real river water samples were successfully quantified by the ABC-reverse transcription (RT)-PCR assay. The quantified values by the ABC-RT-PCR assay very closely resemble those by the real-time RT-PCR assay. In addition, the quantified concentration in most water samples by the ABC-RT-PCR assay was comparable to that by conventional microscopic observation. Thus, Cryptosporidium oocysts in water samples can be accurately and specifically determined by the ABC-RT-PCR assay. As the only equipment that is needed for this end-point fluorescence assay is a simple fluorometer and a relatively inexpensive thermal cycler, this method can markedly reduce time and cost to quantify Cryptosporidium oocysts and other health-related water microorganisms. (C) 2011 Elsevier Ltd. All rights reserved.

    DOI

  • Rapid start-up of a nitrifying reactor using aerobic granular sludge as seed sludge

    Naohiro Kishida, Goro Saeki, Satoshi Tsuneda, Ryuichi Sudo

    WATER SCIENCE AND TECHNOLOGY   65 ( 3 ) 581 - 588  2012年  [査読有り]

     概要を見る

    In this study, the effectiveness of aerobic granular sludge as seed sludge for rapid start-up of nitrifying processes was investigated using a laboratory-scale continuous stirred-tank reactor (CSTR) fed with completely inorganic wastewater which contained a high concentration of ammonia. Even when a large amount of granular biomass was inoculated in the reactor, and the characteristics of influent wastewater were abruptly changed, excess biomass washout was not observed, and biomass concentration was kept high at the start-up period due to high settling ability of the aerobic granular sludge. As a result, an ammonia removal rate immediately increased and reached more than 1.0 kg N/m(3)/d within 20 days and up to 1.8 kg N/m(3)/d on day 39. Subsequently, high rate nitritation was stably attained during 100 days. However, nitrite accumulation had been observed for 140 days before attaining complete nitrification to nitrate. Fluorescence in situ hybridization analysis revealed the increase in amount of ammonia-oxidizing bacteria which existed in the outer edge of the granular sludge during the start-up period. This microbial ecological change would make it possible to attain high rate ammonia removal.

    DOI

  • Alternately binding probe competitive PCR as a simple, cost-effective, and accurate quantification method for JAK2V617F allele burden in myeloproliferative neoplasms

    Soji Morishita, Norio Komatsu, Keita Kirito, Aya H. Koda, Yuji Sekiguchi, Satoshi Tsuneda, Naohiro Noda

    LEUKEMIA RESEARCH   35 ( 12 ) 1632 - 1636  2011年12月  [査読有り]

     概要を見る

    We developed a simple, cost-effective, and accurate JAK2 allele burden quantification method named alternately binding probe competitive PCR (ABC-PCR). ABC-PCR can be performed to quantify target JAK2 allele burdens in a single reaction. The throughput and running cost of ABC-PCR are markedly improved compared with those of allele-specific quantitative PCR (AS-qPCR). The quantification of samples with known JAK2 allele burdens revealed that ABC-PCR had a small assay-to-assay variation. The JAK2 allele burdens in the patients with myeloproliferative neoplasms measured by ABC-PCR and AS-qPCR showed a good fitting. ABC-PCR would be a powerful tool for quantifying target JAK2 allele burdens. (C) 2011 Elsevier Ltd. All rights reserved.

    DOI

  • Synthesis, structure, and biological activity of dumbbell-shaped nanocircular RNAs for RNA interference

    Naoko Abe, Hiroshi Abe, Chisato Nagai, Mitsuru Harada, Hiroto Hatakeyama, Hideyoshi Harashima, Takahito Ohshiro, Mizuki Nishihara, Kazuhiro Furukawa, Mizuo Maeda, Satoshi Tsuneda, Yoshihiro Ito

    Bioconjugate Chemistry   22 ( 10 ) 2082 - 2092  2011年10月

     概要を見る

    RNA interference (RNAi) is one of the most promising new approaches for disease therapy. The design of a dumbbell-shaped nanocircular RNA allows it to act as a short interfering RNA (siRNA) precursor. To optimize the design, we studied the relationship between the nanostructure and RNAi activity by synthesizing various RNA dumbbells. An RNA dumbbell with a 23-bp stem and 9-nt loops was the most potent. Sequence analysis by mass spectrometry showed that Dicer could edit RNA dumbbells to siRNA species. The reaction offered the slow release of siRNA species, which conferred prolonged RNAi activity. Introduction of DNA into the loop position significantly stabilized the dumbbell in biological fluid without any loss of RNAi activity. In-depth pharmacological evaluation was performed by introducing dumbbells into HeLa cells that stably express the target luciferase gene. The dumbbells provided a rapid silencing effect and retained this effect for a longer time even at a lower concentration than that at which standard siRNA completely lost RNAi activity. We conclude that an RNA dumbbell with DNA loops is the most promising design for in vivo applications for RNA medicine. © 2011 American Chemical Society.

    DOI PubMed

  • Significance of Reactor Type for High-Rate Nitrification Using Aerobic Granular Sludge

    Y. Hasebe, M. Eguchi, H. Meguro, S. Tsuneda

    J. Water Environ. Technol.   9 ( 3 ) 289 - 296  2011年09月

    DOI

  • Reproducible subcutaneous transplantation of cell sheets into recipient mice

    Haruko Obokata, Masayuki Yamato, Satoshi Tsuneda, Teruo Okano

    Nature Protocols   6 ( 7 ) 1053 - 1059  2011年06月  [査読有り]

     概要を見る

    Perfecting tissue engineering and cell sheet transplantation is an important step toward realizing regenerative medicine and is a growing area of research. Before being applied to clinical settings, it is important that these approaches are evaluated in vivo. Here we provide a detailed protocol for handling thin cell sheets, for a simple and highly reproducible subcutaneous transplantation of cell sheets into mice, and for the histological examination of regenerated tissues. Various aspects of transplants can be assessed, such as maintenance, differentiation and proliferation. An emphasis is placed on surgical precision and reproducibility. The resulting consistency between surgeries helps minimize artifacts from surgical variation and therefore enables researchers to not only observe and compare the interactions between host tissues but also to compare transplants among different host animals. A single transplantation can be carried out within ∼10 min. © 2011 Nature America, Inc. All rights reserved.

    DOI PubMed

  • Development of osteogenic cell sheets for bone tissue engineering applications.

    Rogério P Pirraco, Haruko Obokata, Takanori Iwata, Alexandra P Marques, Satoshi Tsuneda, Masayuki Yamato, Rui L Reis, Teruo Okano

    Tissue engineering. Part A   17 ( 11-12 ) 1507 - 15  2011年06月  [査読有り]  [国際誌]

     概要を見る

    The use of scaffolds in combination with osteogenic cells has been the gold standard in bone tissue engineering strategies. These strategies have, however, in many cases failed to produce the desired results due to issues such as the immunogenicity of the biomaterials used and cell necrosis at the bulk of the scaffold related to deficient oxygen and nutrients diffusion. Here, we originally propose the use of cell sheet (CS) engineering as a possible way to overcome some of these obstacles. Osteogenic CSs were fabricated by culturing rat bone marrow stromal cells in thermoresponsive culture dishes. The CSs were recovered from the dishes using a low-temperature treatment and then were implanted subcutaneously in nude mice. New bone formation was verified from day 7 post-transplantation using X-ray, microcomputed tomography, and histological analysis. The presence of a vascularized marrow was also verified in the newly formed bone after 6 weeks of transplantation. Further, osteocytes were found in this newly formed tissue, supporting the conclusion that mature bone was formed after ectopically transplanting osteogenic CSs. These results therefore confirm the great potentiality of CS engineering to be used in bone tissue engineering applications.

    DOI PubMed

  • 包括固定化担体を用いた脱窒システムの開発

    井坂和一, 安部直樹, 木村裕哉, 渡部雅智, 大坂利文, 常田聡

    日本水処理生物学会誌   47 ( 2 ) 67 - 74  2011年06月

  • The Potential of Stem Cells in Adult Tissues Representative of the Three Germ Layers

    Haruko Obokata, Koji Kojima, Karen Westerman, Masayuki Yamato, Teruo Okano, Satoshi Tsuneda, Charles A. Vacanti

    TISSUE ENGINEERING PART A   17 ( 5-6 ) 607 - 615  2011年03月  [査読有り]

     概要を見る

    Mature adult tissues contain stem cells that express many genes normally associated with the early stage of embryonic development, when maintained in appropriate environments. Cells procured from adult tissues representative of the three germ layers (spinal cord, muscle, and lung), each exhibiting the potential to mature into cells representative of all three germ layers. Cells isolated from adult tissues of different germ layer origin were propagated as nonadherent clusters or spheres that were composed of heterogeneous populations of cells. When the clusters or spheres were dissociated, the cells had the ability to reform new, nonadherent spheres for several generations. When implanted in vivo, in association with biodegradable scaffolds, into immunodeficient mice, tissue containing cells characteristic of the three germ layers was generated. These findings suggest the existence of a population of stem cells in adult tissues that is quite different and distinct from embryonic stem cells that demonstrate a greater potency for differentiation across germ lines than previously believed. Such cells could potentially be as useful as embryonic stem cells in tissue engineering and regenerative medicine.

    DOI

  • Enhancing Nitrogen and Phosphorus Removal in an Anaerobic/Oxic/Anoxic Sequencing Batch Reactor: The Dependence of the Amount of External Carbon

    K. Soejima, A. Terada, K. Naraki, S. Tsuneda

    J. Water Environ. Technol.   9 ( 1 ) 79 - 86  2011年03月

    DOI

  • ゼオライろ床と植栽を組み合わせた里川再生技術の実河川への適用と維持管理

    木持謙, 金澤光, 真下敏明, 正田武則, 常田聡, 関根正人, 榊原豊

    用水と廃水   53 ( 2 ) 141 - 149  2011年02月

  • Application of nitrifying granules to improvement of nitrification activity in activated sludge process

    Naohiro Kishida, Ryo Totsuka, Atsushi Kono, Mikiya Kurasawa, Motoki Ogiwara, Satoshi Tsuneda

    International Journal of Environment and Waste Management   7 ( 1-2 ) 103 - 111  2011年

     概要を見る

    Nitrifying granules were used to improve nitrification performance of activated sludge process under high organic load. After inoculation of nitrifying granules, nitrification activity immediately increased, and kept for at least 70 days. Fluorescence in situ hybridisation analysis confirmed that nitrifying bacteria were retained in the granules even though nitrifying granules had been served in the organic wastewater treatment reactor for 70 days. Nitrification performance strongly depended on C/N ratio of the influent wastewater. Nitrifying granules that had been statically stored for 100 days could completely recover ammonia removal rate within 15 days after inoculation to ammonia-rich solution. Copyright © 2011 Inderscience Enterprises Ltd.

    DOI

  • Fluorescence Detection of Intron Lariat RNA with Reduction-Triggered Fluorescent Probes

    Kazuhiro Furukawa, Hiroshi Abe, Yasutsugu Tamura, Rei Yoshimoto, Minoru Yoshida, Satoshi Tsuneda, Yoshihiro Ito

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   50 ( 50 ) 12020 - 12023  2011年  [査読有り]

    DOI

  • Behavior of polymeric substrates in an aerobic granular sludge system

    M. K. de Kreuk, N. Kishida, S. Tsuneda, M. C. M. van Loosdrecht

    WATER RESEARCH   44 ( 20 ) 5929 - 5938  2010年12月  [査読有り]

     概要を見る

    Particulate and slowly biodegradable substrates form an important fraction of industrial wastewater and sewage. To study the influence of suspended solids and colloidal substrate on the morphology and performance of aerobic granular sludge, suspended and soluble starch was used as a model substrate. Degradation was studied using microscopy, micro-electrode measurements, batch experiments and long term laboratory scale reactor operation. Starch was removed by adsorption at the granule surface, followed by hydrolysis and consumption of the hydrolyzed products. Aerobic granules could be maintained on starch as sole influent carbon source, but their structure was filamentous and irregular. It is hypothesized that this is related to the low starch hydrolysis rates, leading to available substrate during the aeration period (extended feast period) and resulting in increased substrate gradients over the granules. The latter induces a less uniform granule development. Starch adsorbed and was consumed at the granule surface instead of being accumulated inside the granules as occurs for soluble substrates. Therefore the simultaneous denitrification efficiencies remained low. Moreover, many protozoa and metazoans were observed in laboratory reactors as well as in pilot- and full-scale Nereda(R) reactors, indicating an important role in the removal of suspended solids too. (C) 2010 Elsevier Ltd. All rights reserved.

    DOI

  • Microbial Population Dynamics and Community Structure during the Formation of Nitrifying Granules to Treat Ammonia-Rich Inorganic Wastewater

    Shinya Matsumoto, Daisuke Ishikawa, Goro Saeki, Yoshiteru Aoi, Satoshi Tsuneda

    MICROBES AND ENVIRONMENTS   25 ( 3 ) 164 - 170  2010年09月  [査読有り]

     概要を見る

    Microbial population dynamics were investigated during the formation of nitrifying granules in an aerobic upflow fluidized bed (AUFB) reactor fed ammonia as a sole energy source. Analyses of clone libraries of 16S rRNA gene and the ammonia monooxygenase subunit A gene (amoA) revealed that although the clones obtained from the seed sludge were widely distributed among the ammonia-oxidizing bacteria (AOB) isolates, the community structure of AOB shifted towards the Nitrosomonas mobilis lineage as granulation proceeded. Quantitative fluorescence in situ hybridization showed that changes in the bacterial population occurred concomitantly with changes in nitrification performance and the size of granules. AOB associated with the N. mobilis lineage were predominant in the early stages as nitrifying granules formed (average diameter, 126 mu m). In mature granules (average diameter, 270 mu m), at least three types of AOB, N. mobilis, Nitrosomonas oligotropha, and Nitrosomonas europaea, formed different niches and coexisted. Nitrite-oxidizing bacteria (NOB) affiliated with Nitrospira spp. were detected in the start-up period, but were replaced by NOB affiliated with Nitrobacter spp. after granules formed.

    DOI

  • Formation of Aerobic Granular Sludge in a Continuous Flow Reactor - Control Strategy for Selection of Well-Settling Granular Sludge -

    N. Kishida, A. Kono, Y. Yamashita, S. Tsuneda

    J. Water Environ. Technol.   8 ( 3 ) 251 - 258  2010年09月

    DOI

  • New monitoring approach for metabolic dynamics in microbial ecosystems using stable-isotope-labeling technologies

    Yasuhiro Date, Yumiko Nakanishi, Shinji Fukuda, Tamotsu Kato, Satoshi Tsuneda, Hiroshi Ohno, Jun Kikuchi

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   110 ( 1 ) 87 - 93  2010年07月  [査読有り]

     概要を見る

    We have developed a new approach for monitoring the metabolic dynamics in microbial ecosystems using a combination of DNA fingerprinting and metabolome analysis based on stable-isotope-labeling technologies. Stable-isotope probing of DNA (DNA-SIP) has been used previously for the evaluation of cross-feeding in microbial communities. For the development and validation of our monitoring approach, fecal microbiota were analyzed with stable-isotope-labeled glucose used as the sole carbon source. In order to link the metabolic information and the microbial variability, we performed metabolic-microbial correlation analysis based on nuclear magnetic resonance (NMR) profiles and denaturing gradient gel electrophoresis (DGGE) fingerprints, which successfully identified the glucose-utilizing bacteria and their related extracellular metabolites. Moreover, our approach revealed information regarding the carbon flux, in that the "first" wave of extracellular metabolites secreted by the glucose-utilizing bacteria were incorporated into the "secondary" group of substrate-utilizing bacteria, and that this "secondary" group further produced their own secondary metabolized substrates. Thus, this approach is a powerful tool for monitoring the metabolic dynamics in microbial ecosystems and allows for the tracking of the carbon flux within a microbial community. (C) 2010, The Society for Biotechnology, Japan. All rights reserved.

    DOI

  • Direct cloning and expression of putative esterase genes from environmental DNA

    Takeshi Terahara, Kazutaka Yamada, Shinya Kurata, Toyokazu Yokomaku, Satoshi Tsuneda, Shigeaki Harayama

    ENZYME AND MICROBIAL TECHNOLOGY   47 ( 1-2 ) 17 - 23  2010年07月  [査読有り]

     概要を見る

    Putative esterase genes were isolated from environmental DNA by using pre-amplified inverse PCR. The sequence analysis of the isolated genes showed 32-80% amino acid sequence identities to known esterases/lipases in public databases. The isolated genes were subsequently expressed in recombinant Escherichia coli. Insoluble proteins were noted in the expression of the majority of the isolated genes. The findings suggest that it is difficult to isolate these genes by using activity-based screening with construction of metagenome library. For the enzymes characterized, we examined substrate specificity, optimal temperature, optimal pH, and thermal stability. The substrate specificity of all the enzymes was high for p-nitrophenyl acetate, but almost undetectable for p-nitrophenyl decanoate. The results indicate that the obtained enzymes are defined as esterases. The enzymes were active in a broad range of temperature. The optimum activity was observed at 25-70 degrees C and at pH 8.0-9.0. Some enzymes have moderate thermostability and would be useful for industrial enzymes. This study illustrates that pre-amplified inverse PCR, which is one of the sequence-based approach, is potentially applicable to the isolation of diverse genes from environmental DNA. (C) 2010 Elsevier Inc. All rights reserved.

    DOI

  • Quantitative detection of chloroethene-reductive bacteria Dehalococcoides spp. using alternately binding probe competitive polymerase chain reaction

    Ryo Miyata, Ken Adachi, Hidenori Tani, Shinya Kurata, Kazunori Nakamura, Satoshi Tsuneda, Yuji Sekiguchi, Naohiro Noda

    MOLECULAR AND CELLULAR PROBES   24 ( 3 ) 131 - 137  2010年06月  [査読有り]

     概要を見る

    Dehalococcoides spp. are responsible for the reductive dehalogenation of environmental contaminants and are candidates for engineered bioremediation. The development of a sensitive, reliable, and rapid method for the quantification of Dehalococcoides spp. is required for the effective use of the organisms in bioremediation sites. Here, we describe the quantification of the 16S rRNA gene of Dehalococcoides spp. using a recently developed quantification method named alternately binding probe competitive PCR (ABC-PCR). The primers and probe sets that were newly designed for ABC-PCR were found to have a high specificity for Dehalococcoides spp. The standard curve of ABC-PCR had a good fitting (R = 0.999), and the lower detection limit was 10 copies/mu l of template DNA. We also investigated the effects of inherent PCR-inhibiting compounds in an environmental sample on the quantification using ABC-PER or real-time PCR by adding the soil extraction solution to PCR mixtures. ABC-PCR was more robust against the PER amplification inhibitors than real-time PCR. The copy number of the 16S rRNA gene of Dehalococcoides spp. in soil and groundwater samples was successfully quantified using ABC-PER. In conclusion, ABC-PCR is useful for the quantification of Dehalococcoides spp. populations and dynamics at bioremediation sites. (C) 2009 Elsevier Ltd. All rights reserved.

    DOI

  • 単一槽型窒素除去を志向したバイオフィルムリアクターの進展

    寺田昭彦, 常田聡

    水環境学会誌   33 ( 4 ) 114 - 120  2010年04月

  • Real-time monitoring of RNA helicase activity using fluorescence resonance energy transfer in vitro

    Hidenori Tani, Osamu Fujita, Atsushi Furuta, Yasuyoshi Matsuda, Ryo Miyata, Nobuyoshi Akimitsu, Junichi Tanaka, Satoshi Tsuneda, Yuji Sekiguchi, Naohiro Noda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   393 ( 1 ) 131 - 136  2010年02月  [査読有り]

     概要を見る

    We have developed a continuous fluorescence assay based on fluorescence resonance energy transfer (FRET) for the monitoring of RNA helicase activity in vitro. The assay is tested using the hepatitis C virus (HCV) NS3 helicase as a model. We prepared a double-stranded RNA (dsRNA) substrate with a 5&apos; fluorophore-labeled strand hybridized to a 3&apos; quencher-labeled strand. When the dsRNA is unwound by helicase, the fluorescence of the fluorophore is emitted following the separation of the strands. Unlike in conventional gel-based assays, this new assay eliminates the complex and time-consuming steps, and can be used to simply measure the real-time kinetics in a single helicase reaction. Our results demonstrate that Alexa Fluor 488 and BHQ1 are an effective fluorophore-quencher pair, and this assay is suitable for the quantitative measurement of the RNA helicase activity of HCV NS3. Moreover, we found that several extracts of marine organisms exhibited different inhibitory effects on the RNA and DNA helicase activities of HCV NS3. We propose that this assay will be useful for monitoring the detailed kinetics of RNA unwinding mechanisms and screening RNA helicase inhibitors at high throughput. (C) 2010 Elsevier Inc. All rights reserved.

    DOI

  • Transitions in Oral and Intestinal Microflora Composition and Innate Immune Receptor-Dependent Stimulation during Mouse Development

    Mizuho Hasegawa, Toshifumi Osaka, Kazuki Tawaratsumida, Takashi Yamazaki, Hiroyuki Tada, Grace Y. Chen, Satoshi Tsuneda, Gabriel Nunez, Naohiro Inohara

    INFECTION AND IMMUNITY   78 ( 2 ) 639 - 650  2010年02月  [査読有り]

     概要を見る

    Commensal bacteria possess immunostimulatory activities that can modulate host responses to affect development and homeostasis in the intestine. However, how different populations of resident bacteria stimulate the immune system remains largely unknown. We characterized here the ability of intestinal and oral microflora to stimulate individual pattern recognition receptors (PRRs) in bone marrow-derived macrophages and mesothelial cells. The intestinal but not oral microflora elicited age-and cell type-specific immunostimulation. The immunostimulatory activity of the intestinal microflora varied among individual mice but was largely mediated via Toll-like receptor 4 (TLR4) during breast-feeding, whereas it became TLR4 independent after weaning. This transition was associated with a change from a microflora rich in TLR4-stimulatory proteobacteria to one dominated by Bacteroidales and/or Clostridiales that poorly stimulate TLR4. The major stimulatory activity of the intestinal microflora was still intact in NOD1-, NOD2-, TLR2-, TLR4-, TLR5-, TLR9-, TLR11-, ASC-, or RICK-deficient cells but still relied on the adaptor MyD88. These studies demonstrate a transition in the intestinal microflora accompanied by a dynamic change of its ability to stimulate different PRRs which control intestinal homeostasis.

    DOI

  • 好気性グラニュールを用いた新しい水処理技術

    岸田直裕, 常田聡

    月刊浄化槽   406   14 - 18  2010年02月

  • Photoactivatable fluorescein derivatives with azidomethyl caging groups for tracing oligonucleotides in living human cells

    Kazuhiro Furukawa, Hiroshi Abe, Satoshi Tsuneda, Yoshihiro Ito

    ORGANIC & BIOMOLECULAR CHEMISTRY   8 ( 10 ) 2309 - 2311  2010年  [査読有り]

     概要を見る

    A new photocaged fluorescent compound, azidomethyl fluorescein, was successfully utilized to monitor the dynamics of oligonucleotides in living human cells.

    DOI

  • Microbial Community Structure in Autotrophic Nitrifying Granules Characterized by Experimental and Simulation Analyses

    S. Matsumoto, M. Katoku, G. Saeki, A. Terada, Y. Aoi, S. Tsuneda, C. Picioreanu, M.C.M. van Loosdrecht

    Environ. Microbiol.   12 ( 1 ) 192 - 206  2009年12月

  • Reduction-Triggered Fluorescence Probe for Peptide-Templated Reactions

    Aya Shibata, Hiroshi Abe, Kazuhiro Furukawa, Satoshi Tsuneda, Yoshihiro Ito

    CHEMICAL & PHARMACEUTICAL BULLETIN   57 ( 11 ) 1223 - 1226  2009年11月  [査読有り]

     概要を見る

    We developed a new nucleic acid-based fluorescence probe for protein detection. The method is based on the scission of an aptamer into two probes, which are then attached with a chemically reactive fluorogenic compound. The protein-dependent association of the two probes accelerates a reduction-triggered fluorogenic reaction and indicates the presence of the target protein. which is detected using a fluorescence readout. The fluorescence signal is generated via the deprotection of the azidomethyl group of fluorescein. The arginine-rich motif peptide of the human immunodeficiency virus-1 Rev protein was targeted by this type of probe. Emission was detected at 522 nm and was enhanced by about 19.4-fold in the presence of the target peptide. An oligonucleotide-based reduction-1 triggered fluorescence probe was successfully applied to the defection of the Rev peptide ill solution.

  • Characterization of the Microbial Community in the Anaerobic/Oxic/Anoxic Process Combined with Sludge Ozonation and Phosphorus Adsorption

    T. Kondo, S. Tsuneda, Y. Ebie, Y. Inamori, K. Xu

    J. Water Environ. Technol.   7 ( 3 ) 155 - 162  2009年09月

  • Universal Quenching Probe System: Flexible, Specific, and Cost-Effective Real-Time Polymerase Chain Reaction Method

    Hidenori Tani, Ryo Miyata, Kouhei Ichikawa, Soji Morishita, Shinya Kurata, Kazunori Nakamura, Satoshi Tsuneda, Yuji Sekiguchi, Naohiro Noda

    ANALYTICAL CHEMISTRY   81 ( 14 ) 5678 - 5685  2009年07月  [査読有り]

     概要を見る

    We have developed a flexible, specific, and cost-effective real-time polymerase chain reaction (PCR) method. In this technique, a quenching probe (QProbe) and a nonfluorescent 3&apos;-tailed probe are used. The QProbe is a singly labeled oligonucleotide bearing a fluorescent dye that is quenched via electron transfer between the dye and a guanine base at a particular position. The nonfluorescent 3&apos;-tailed probe consists of two parts: one is the target-specific sequence on the 5&apos; side, and the other is complementary to the QProbe on the 3&apos; side. When the QProbe/nonfluorescent 3&apos;-tailed probe complex hybridizes with the target in PCR, the fluorescence of the dye is quenched. Fluorescence quenching efficiency is proportional to the amount of the target. We called this method the universal QProbe system. This method substantially reduces the cost of real-time PCR setup because the same QProbe can be used for different target sequences. Moreover, this method allows accurate quantification even in the presence of nonspecific PCR products because the use of nonfluorescent 3&apos;-tailed probe significantly increases specificity. Our results demonstrate that this method can accurately and reproducibly quantify specific nucleic acid sequences in crude samples, comparable with conventional TaqMan chemistry. Furthermore, this method is also applicable to single-nucleotide polymorphism (SNP) genotyping.

    DOI

  • Improvement of Nutrient Removal and Phosphorus Recovery in the Anaerobic/Oxic/Anoxic Process Combined with Sludge Ozonation and Phosphorus Adsorption

    T. Kondo, S. Tsuneda, Y. Ebie, Y. Inamori, K. Xu

    J. Water Environ. Technol.   7 ( 2 ) 135 - 142  2009年06月

  • Hollow-Fiber Membrane Chamber as a Device for In Situ Environmental Cultivation

    Yoshiteru Aoi, Tomoyuki Kinoshita, Toru Hata, Hiroaki Ohta, Haruko Obokata, Satoshi Tsuneda

    APPLIED AND ENVIRONMENTAL MICROBIOLOGY   75 ( 11 ) 3826 - 3833  2009年06月  [査読有り]

     概要を見る

    A hollow-fiber membrane chamber (HFMC) was developed as an in situ cultivation device for environmental microorganisms. The HFMC system consists of 48 to 96 pieces of porous hollow-fiber membrane connected with injectors. The system allows rapid exchange of chemical compounds, thereby simulating a natural environment. Comparative analysis through the cultivation of three types of environmental samples was performed using this newly designed device and a conventional agar-based petri dish. The results show that the ratios of novel phylotypes in isolates, species-level diversities, and cultivabilities in HFMC-based cultivation are higher than those in an agar-based petri dish for all three samples, suggesting that the new in situ cultivation device is effective for cultivation of various environmental microorganisms.

    DOI

  • Affinity capillary electrophoresis with magnetic beads for multiplex quantitative analysis of bacterial 16S rRNA

    Ken Adachi, Masahiro Yamaguchi, Makoto Nakashige, Takahiro Kanagawa, Masaki Torimura, Satoshi Tsuneda, Yuji Sekiguchi, Naohiro Noda

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   107 ( 6 ) 662 - 667  2009年06月  [査読有り]

     概要を見る

    We have developed a novel method for microbial community analysis of bacterial 16S rRNAs based on affinity capillary electrophoresis using 16S rRNA-conjugated magnetic beads. We called this method magnetic beads affinity capillary electrophoresis (MB-ACE) which can be used for sequential and quantitative analysis of 16S rRNA. In this method, RNA extracted from a microbial community is biotin-modified and mixed with streptavidin-modified paramagnetic beads. This mixture is then injected into a capillary and localized in the middle of the capillary using a magnet held adjacent to the capillary. Subsequently, a fluorescent-labeled probe to detect the target 16S rRNA is injected into the capillary, and voltage is applied. The probe trapped on the RNA is dissociated by formamide and detected at its anodic end by measuring the fluorescence. Next, another fluorescent probe is injected, and thus the target 16S rRNA in the sample is quantified one by one. MB-ACE was used for the quantification of the 16S rRNAs of Escherichia coli and Pseudomonas putida in samples that were prepared by mixing RNA extracted from activated sludge and 16S rRNAs prepared by in vitro transcription. The two types of 16S rRNAs were quantified, indicating that MB-ACE can be used for sequential quantitative analysis of bacterial 16S rRNAs. (C) 2009, The Society for Biotechnology, Japan. All rights reserved.

    DOI

  • Reduction-Triggered Fluorescent Amplification Probe for the Detection of Endogenous RNAs in Living Human Cells

    Kazuhiro Furukawa, Hiroshi Abe, Kayo Hibino, Yasushi Sako, Satoshi Tsuneda, Yoshihiro Ito

    BIOCONJUGATE CHEMISTRY   20 ( 5 ) 1026 - 1036  2009年05月  [査読有り]

     概要を見る

    Oligonucleotide-templated reactions are attracting attention as a method for RNA detection in living cells. Previously, a reduction-triggered fluorescence probe has been reported that is based on azide reduction to switch fluorescence on. In this article, we report a more advanced probe, a reduction-triggered fluorescent amplification probe that is capable of amplifying a target signal. Azidomethyl fluorescein was newly synthesized and introduced into a probe. Azido-masked fluorescein on the probe showed a strong turn-on fluorescence signal upon oligonucleotide-templated Staudinger reduction. The catalytic reaction of the probe offered a turnover number of 50 as fluorescence readout within 4 h. Finally, probes were introduced into human leukemia HL-60 cells by use of streptolysin O pore-forming peptide. We successfully detected and quantitated the 28S rRNA and P-Actin mRNA signal above the background by flow cytometry. In addition, the same RNA targets were imaged by fluorescence microscopy. The data suggest that a reduction-triggered amplification probe may be a powerful tool in analyzing the localization, transcription, or processing of RNA species in living eukaryotic cells.

    DOI

  • Real-time reverse transcription loop-mediated isothermal amplification for rapid and simple quantification of WT1 mRNA

    Soji Morishita, Hidenori Tani, Sinya Kurata, Kazunori Nakamura, Satoshi Tsuneda, Yuji Sekiguchi, Naohiro Noda

    CLINICAL BIOCHEMISTRY   42 ( 6 ) 515 - 520  2009年04月  [査読有り]

     概要を見る

    Objectives: This Study developed a novel MRD monitoring method targeting Wilms&apos; tumor gene (WT1) mRNA Using reverse transcription loop-mediated isothermal amplification (RT-LAMP).
    Design and methods: A primer set for the assay was designed oil the basis of the sequences between the 17AA and KIN regions of WT1 mRNA. WT1 mRNA was quantified by real-time RT-LAMP and the accuracy of RT-LAMP was compared with that of real-time RT-PCR.
    Results: The standard curve was expressed as a linear relationship between the log copy numbers of WT1 mRNA ranging from 6.8 x 10 to 6.8 x 10(9) copies and the threshold time with a correlation coefficient of R(2)&gt;0.994. The measured values obtained by RT-LAMP strongly correlated with those obtained by real-time RT-PCR.
    Conclusion: RT-LAMP can be used to determine WT1 mRNA expression levels. This assay will contribute to a more specific, simple, and rapid MRD monitoring than conventional assays. (C) 2009 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

    DOI

  • 新規分離培養手法の開発とその意義

    青井議輝, 常田聡

    生物工学   87 ( 4 ) 179 - 182  2009年04月

  • Simultaneous Nitrogen and Phosphorus Removal from High-Strength Industrial Wastewater Using Aerobic Granular Sludge

    N. Kishida, S. Tsuneda, J. H. Kim, R. Sudo

    JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE   135 ( 3 ) 153 - 158  2009年03月  [査読有り]

     概要を見る

    Aerobic granular sludge technology was applied to the simultaneous nitrogen and phosphorus removal from livestock wastewater that contains high concentrations of nitrogen and phosphorus (TN: 650 mg/L; TP: 125 mg/L). A lab-scale sequencing batch reactor was operated in an alternating anaerobic/oxic/anoxic denitrification mode. Granular sludge was first formed using synthetic wastewater. When livestock wastewater was diluted with tap water, the shape and settleability of aerobic granular sludge were maintained even though livestock wastewater contained suspended solids. Simultaneous nitrification, denitrification, and phosphate uptake were observed under an aerobic condition. However, when nondiluted livestock wastewater was used, the diameter of granular sludge and the denitrification efficiency under an oxic condition decreased. When the concentrations of nitrogen and phosphorus in wastewater increased, hydraulic retention time (HRT) increased resulting in a decrease in selection pressure for granular sludge. Therefore, the sustainment of granular sludge was difficult in livestock wastewater treatment. However, by applying a new excess sludge discharge method based on Stokes&apos; law, the shape of granular sludge was maintained in spite of the long HRT (7.5 days). To select large granular sludge particles, excess sludge was discharged from the upper part of settled sludge because small particles localized there after settling. Finally, excellent nitrogen and phosphorus removal was accomplished in practical livestock wastewater treatment. The effluent concentrations of NH(4)-N, NO(x)-N, and PO(4)-P were &lt; 0.1, 1.4, and 1.2 mg/L, respectively.

    DOI

  • Microbial diversity of anammox bacteria enriched from different types of seed sludge in an anaerobic continuous-feeding cultivation reactor

    Yasuhiro Date, Kazuichi Isaka, Hajime Ikuta, Tatsuo Sumino, Naoya Kaneko, Sachiko Yoshie, Satoshi Tsuneda, Yuhei Inamori

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   107 ( 3 ) 281 - 286  2009年03月  [査読有り]

     概要を見る

    Enrichment of anammox bacteria from three types of seed sludge, sewage, digester, and nitrification sludges, was conducted using a nonwoven fabric carrier for immobilizing the anammox bacteria, and the microbial diversity of the enriched anammox culture was investigated. About four months later, simultaneous removals of ammonium and nitrite, and production of a small amount of nitrate, which is unique to the anammox reaction, were observed in all 3 sludge reactors. Results of 16S rRNA gene analysis indicated that anammox bacteria were cultivated and diversified in each sludge type. Moreover, the microbial diversity of anammox bacteria was higher in the enriched culture from sewage sludge compared to the other two types of seed sludge. Bacillus sp. coexisted in the anammox culture cultivated from sewage sludge. These results suggest that differences in the anammox community in the enriched culture were caused by differences in the type of seed sludge. (C) 2008, The Society for Biotechnology, Japan. All rights reserved.

    DOI

  • Molecular diversity of bacterial chitinases in arable soils and the effects of environmental factors on the chitinolytic bacterial community

    Takeshi Terahara, Seishi Ikeda, Chiaki Noritake, Kiwamu Minamisawa, Katsuhiko Ando, Satoshi Tsuneda, Shigeaki Harayama

    SOIL BIOLOGY & BIOCHEMISTRY   41 ( 3 ) 473 - 480  2009年03月  [査読有り]

     概要を見る

    The molecular diversity of bacterial chitinases in the bulk soils of arable land was investigated using culture-independent methods. The results demonstrate that bacterial chitinases in arable soils are highly diverse and comprise unique groups when their sequences were compared to those in public databases. The diversity of bacterial chitinases in arable soil was further evaluated using conventional phylogenetic analysis, the UniFrac analysis of the phylogenetic data, and the multidimensional scaling (MDS) analysis of T-RFLP profiles to elucidate the relationship between the diversity of bacterial chitinases and soil characteristics. These analyses indicate that environmental factors such as soil type and pH are responsible for shaping the composition of bacterial chitinases. (C) 2008 Elsevier Ltd. All rights reserved.

    DOI

  • High-throughput screening assay of hepatitis C virus helicase inhibitors using fluorescence-quenching phenomenon

    Hidenori Tani, Nobuyoshi Akimitsu, Osamu Fujita, Yasuyoshi Matsuda, Ryo Miyata, Satoshi Tsuneda, Masayuki Igarashi, Yuji Sekiguchi, Naohiro Noda

    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS   379 ( 4 ) 1054 - 1059  2009年02月  [査読有り]

     概要を見る

    We have developed a novel high-throughput screening assay of hepatitis C virus (HCV) nonstructural protein 3 (NS3) helicase inhibitors using the fluorescence-quenching phenomenon via photoinduced electron transfer between fluorescent dyes and guanine bases. We prepared double-stranded DNA (dsDNA) with a 5&apos;-fluorescent-dye (BODIPY FL)-labeled strand hybridized with a complementary strand, the 3&apos;-end of which has guanine bases. When dsDNA is unwound by helicase, the dye emits fluorescence owing to its release from the guanine bases. Our results demonstrate that this assay is suitable for quantitative assay of HCV NS3 helicase activity and useful for high-throughput screening for inhibitors. Furthermore, we applied this assay to the Screening for NS3 helicase inhibitors from cell extracts Of Microorganisms, and found several cell extracts containing potential inhibitors. (C) 2009 Elsevier Inc. All rights reserved.

    DOI

  • Protein detection using oligonucleotide probes.

    Shibata Aya, Abe Hiroshi, Furukawa Kazuhiro, Tsuneda Satoshi, Ito Yoshihiro

    Nucleic acids symposium series (2004)   ( 53 ) 157 - 158  2009年  [査読有り]

     概要を見る

    We developed a new nucleic acid-based fluorescence probe for protein detection. The method is based on the scission of an aptamer into two probes, which are then attached with a chemically reactive fluorogenic compound. The protein-dependentassociation of the two probes accelerates a chemical reaction and indicates the presence of the target protein, which is detected using a fluorescence readout. The arginine-rich motif peptide was targeted by this type of probe. In presence of the peptide, the fluorescence signal at 450 nm increased, and no significant increase influorescence was observed in the absence of the peptide. An oligonucleotide-based fluorescence probe was successfully applied to the detection of the ARM peptide in solution.

    DOI PubMed

  • Reduction-triggered red fluorescent probes for dual-color detection of oligonucleotide sequences

    Kazuhiro Furukawa, Hiroshi Abe, Jin Wang, Miwako Uda, Hiroyuki Koshino, Satoshi Tsuneda, Yoshihiro Ito

    ORGANIC & BIOMOLECULAR CHEMISTRY   7 ( 4 ) 671 - 677  2009年  [査読有り]

     概要を見る

    We have developed a new red fluorogenic compound derived from naphthorhodamine for a reduction-triggered fluorescence probe to sense oligonucleotides. The fluorogenic reaction between naphthorhodamine azide derivatives and reducing reagents such as triphenylphosphine (TPP) on the DNA target does not use any enzyme or reagent, and fluoresces at 650 nm. The probes were used for dual color detection of a single nucleotide difference on the leukemia-related bcr/abl gene.

    DOI

  • Fibrous Support Stabilizes Nitrification Performance of a Membrane-Aerated Biofilm: The Effect of Liquid Flow Perturbation

    Akihiko Terada, Junpei Ito, Shinya Matsumoto, Satoshi Tsuneda

    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN   42 ( 8 ) 607 - 615  2009年  [査読有り]

     概要を見る

    Nitrification stability and biofilm robustness were examined by comparing a fibrous support membrane-aerated biofilm reactor (FS-MABR), where a woven fibrous support was surrounded on a silicone tube, with an MABR. The overall mass transfer coefficient of oxygen for the FS-MABR, assuming no boundary layer between the fibrous material and bulk liquid, was 5.85 m/d at an air pressure of 27 kPa, which was comparable to that value of the MABR (5.54 m/d). The amount of biomass on the fibrous support with a silicone tube was 2.48 times larger than on the bare silicone. The biomass loss after a high liquid flow rate condition was 49% and 75% in the FS-MABR and MABR, exhibiting robust biofilms grown on the fibrous support. The FS-MABR provided more stable nitrification performance than the MABR irrespective of a high liquid flow rate. Both reactors have deteriorated ammonium (NH(4)(+)-N) removal without a high liquid flow rate condition to eliminate excessive biomass, indicating that regular maintenance is essential to eliminate excessive biofilm from a MABR for nitrification, which potentially acts as a NH(4)(+) diffusion barrier.

  • Anaerobic ammonium oxidation (anammox) irreversibly inhibited by methanol

    Kazuichi Isaka, Yuichi Suwa, Yuya Kimura, Takao Yamagishi, Tatsuo Sumino, Satoshi Tsuneda

    APPLIED MICROBIOLOGY AND BIOTECHNOLOGY   81 ( 2 ) 379 - 385  2008年11月  [査読有り]

     概要を見る

    Methanol inhibition of anaerobic ammonium oxidation (anammox) activity was characterized. An enrichment culture entrapped in a polyethylene glycol gel carrier was designed for practical uses of wastewater treatment. Batch experiments demonstrated that anammox activity decreased with increases in methanol concentration, and relative activity reached to 29% of the maximum when 5 mM methanol was added. Also, batch experiments were conducted using anammox sludge without immobilization. Anammox activity was evaluated by quantifying (NN)-N-14-N-15 (N-29) emission by combined gas chromatography-quadrupole mass spectrometry, and the anammox activity was found to be almost as sensitive to methanol as in the earlier trials in which gel carriers were used. These results indicated that methanol inhibition was less severe than previous studies. When methanol was added in the influent of continuous feeding system, relative activity was decreased to 46% after 80 h. Although the addition was halted, afterwards the anammox activity was not resumed in another 19 days of cultivation, suggesting that methanol inhibition to anammox activity was irreversible. It is notable that methanol inhibition was not observed if anammox activity was quiescent when substrate for anammox was not supplied. These results suggest that methanol itself is not inhibitory and may not directly inhibit the anammox activity.

    DOI

  • Subcutaneous transplantation of autologous oral mucosal epithelial cell sheets fabricated on temperature-responsive culture dishes

    Haruko Obokata, Masayuki Yamato, Joseph Yang, Kohji Nishida, Satoshi Tsuneda, Teruo Okano

    JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A   86A ( 4 ) 1088 - 1096  2008年09月  [査読有り]

     概要を見る

    The oral mucosa is an attractive cell source for autologous transplantation in human patients who require regenerative therapies of various epithelia. However, the tune-course of cellular changes in transplanted oral mucosal epithelia at ectopic sites remains poorly understood. By applying a rat model, we analyzed phenotypic changes in oral mucosal epithelial cell sheets after harvest from temperature-responsive culture dishes and subsequent autologous subcutaneous transplantation. We used monoclonal antibodies to identify epithelial-specific cytokeratins 4, 10, 13, and 14, the stem/progenitor cell marker p63, and proliferating cell nuclear antigen, within the regenerated tissues. Transplanted oral mucosal epithelial cell sheets proliferated during the first week after grafting in conjunction with host inflammation, but then began to degenerate afterward with complete disappearance after 3 weeks. Our findings suggest that host subcutaneous tissues support proliferation and differentiation of the oral mucosal epithelial cell sheets, but are unable to promote maintenance of stern and progenitor cells and therefore cannot produce long-term survivability. (c) 2007 Wiley Periodicals, Inc.

    DOI

  • ダンベル型ナノサークルRNAでRNA干渉を長期安定に

    阿部洋, 阿部奈保子, 原田充, 常田聡, 伊藤嘉浩

    バイオサイエンスとインダストリー   66 ( 8 ) 453 - 455  2008年08月

  • Effects of carbon source on denitrification efficiency and microbial community structure in a saline wastewater treatment process

    Toshifumi Osaka, Kosuke Shirotani, Sachiko Yoshie, Satoshi Tsuneda

    WATER RESEARCH   42 ( 14 ) 3709 - 3718  2008年08月  [査読有り]

     概要を見る

    Two different denitrifying reactors were monitored in order to evaluate the effects of carbon source on denitrification efficiency and microbial community structure under various saline conditions. Nitrogen removal performances were determined when salinity concentrations increase gradually in acetate- or methanol-fed denitrifying reactor. As a result, acetate-fed process attained high nitrate removal at 0-10% NaCl, while methanol was proven beneficial electron donors at 0-3% NaCl. A parallel analysis of T-RFLP and cloning in the acetate-fed sludge showed that a specialized microbial population (i.e. the genera Halomonas and Marinobacter) adapted to a high saline environment. Meanwhile, there were no major changes of bacterial populations in the methanol-fed reactor at 4% NaCl, although the relative abundances of the genera Azoarcus and Methylophaga increased when salinity concentration was at 1-3% NaCl, indicating that methanol-utilizing populations in activated sludge was unable to adapt to a high saline environments (&gt;4% NaCl). (C) 2008 Elsevier Ltd. All rights reserved.

    DOI

  • Fluorescence generation from tandem repeats of a malachite green RNA aptamer using rolling circle transcription

    Kazuhiro Furukawa, Hiroshi Abe, Naoko Abe, Mitsuru Harada, Satoshi Tsuneda, Yoshihiro Ito

    BIOORGANIC & MEDICINAL CHEMISTRY LETTERS   18 ( 16 ) 4562 - 4565  2008年08月  [査読有り]

     概要を見る

    We demonstrate a generation of tandem repeats of a malachite green (MG) RNA aptamer using rolling circle transcription. To keep the higher-order structure of each aptamer on long RNA, we designed a sequence of circular DNA with a 14-base linker. T7 RNA polymerase was superior to Escherichia coli RNA polymerase in the specific transcription of the MG RNA aptamer. Finally. the generation of the fluorescence signal was confirmed from aptamer repeats with MG. (c) 2008 Elsevier Ltd. All rights reserved.

    DOI

  • 水処理プロセスにおけるリン資源の除去・廃棄から回収・資源化へのパラダイムシフト

    蛯江美孝, 近藤貴志, 徐 開欽, 常田 聡, 杉浦則夫, 丸山 治, 稲森 悠平

    ケミカルエンジニヤリング   53 ( 7 ) 530 - 535  2008年07月

  • Modeling and experimental study on the anaerobic/aerobic/anoxic process for simultaneous nitrogen and phosphorus removal: The effect of acetate addition

    Koichi Soejima, Shinya Matsumoto, Satoshi Ohgushi, Kensuke Naraki, Akihiko Terada, Satoshi Tsuneda, Akira Hirata

    PROCESS BIOCHEMISTRY   43 ( 6 ) 605 - 614  2008年06月  [査読有り]

     概要を見る

    A mathematical model based on the simulation software AQUASIM was developed to validate an anaerobic/aerobic/anoxic (AOA) process that enables simultaneous nitrogen and phosphorus removal in a single reactor by adding external organic carbon to preclude excess aerobic phosphate uptake by polyphosphate-accumulating organisms (PAOs) and provide phosphate for denitrifying PAOs (DNPAOs). Aerobic batch tests after anaerobic phosphate release with different chemical oxygen demand (COD) concentrations indicated that the effect of COD concentration on the phosphate uptake preclusion could be expressed by a simple formula. The reduction factor reflecting the formula, which retards the aerobic phosphate uptake in the presence of COD, was added to the process rates of aerobic polyphosphate storage and PAOs growth in the model. The improved model, which included the reduction factor, reasonably matched the experimental result regarding aerobic phosphate uptake behavior whereas the model without it did not; thus, the former precisely predicts the AOA process behavior. (C) 2008 Elsevier Ltd. All rights reserved.

    DOI

  • 細胞内遺伝子シグナルの解析

    阿部洋, 古川和寛, 常田聡, 伊藤嘉浩

    生物工学   86 ( 5 ) 268 - 270  2008年06月

  • A reduction-triggered fluorescence probe for sensing nucleic acids

    Hiroshi Abe, Jin Wang, Kazuhiro Furukawa, Kazuma Oki, Miwako Uda, Satoshi Tsuneda, Yoshihiro Ito

    BIOCONJUGATE CHEMISTRY   19 ( 6 ) 1219 - 1226  2008年06月  [査読有り]

     概要を見る

    We have developed a reduction-triggered fluorescence probe with a new fluorogenic compound derivatized from Rhodamine for sensing oligonucleotides. The chemistry to activate the compound involves the reaction between the azide group of rhodamine derivatives and the reducing reagents, with the fluorescence signal appearing after reduction of the azide group. The signal/background ratio of this fluorogenic compound reached 2100-fold enhancement in fluorescence intensity. Dithio-1,4-threitol or triphenylphosphine as reducing reagents were successfully utilized for this chemistry to be introduced into the DNA probe. The genetic detection requires that two strands of DNA bind onto target oligonticleotides, one probe carrying a reducible fluorogenic compound while the other carries the reducing reagents. The reaction proceeds automatically without any enzymes or reagents under biological conditions to produce a fluorescence signal within 10-20 min in the presence of target DNA or RNA. In addition, the probe was very stable tinder biological conditions, even such extreme conditions as pH 5 solution, pH 10 solution, or high temperature (90 degrees C) with no undesirable background signal. The probes were successfully applied to the detection of oligonucleotides at the single nucleotide level in solution and endogenous RNA in bacterial cells.

    DOI

  • Nitrogen removal performance using anaerobic ammonium oxidation at low temperatures

    Kazuichi Isaka, Yasuhiro Date, Yuya Kimura, Tatsuo Sumino, Satoshi Tsuneda

    FEMS MICROBIOLOGY LETTERS   282 ( 1 ) 32 - 38  2008年05月  [査読有り]

     概要を見る

    An anaerobic ammonium oxidation (anammox) process for ammonia-rich wastewater treatment has not been reported at temperatures below 15 degrees C. This study used a gel carrier with entrapped anammox bacteria to obtain a stable nitrogen removal performance at low temperatures. In a continuous feeding test, a high nitrogen conversion rate (6.2 kg N m(-3) day(-1)) was confirmed at 32 degrees C. Nitrogen removal activity decreased gradually with decreasing operation temperature; however, it still occurred at 6 degrees C. Nitrogen conversion rates at 22 and 6.3 degrees C were 2.8 and 0.36 kg N m(-3) day(-1), respectively. Moreover, the stability of anammox activity below 20 degrees C was confirmed for more than 130 days. In batch experiments, anammox gel carriers were characterized with respect to temperature. The optimum temperature for anammox bacteria was found to be 37 degrees C. Furthermore, it was clear that the temperature dependence changed at about 28 degrees C. The apparent activation energy in the temperature range from 22 to 28 degrees C was calculated as 93 kJ mol(-1), and that in the range from 28 to 37 degrees C was 33 kJ mol(-1). This value agrees with the result of a continuous feeding test (94 kJ mol(-1), between 6 and 22 degrees C). The nitrogen removal performance demonstrated at the low temperatures used in this study will open the door for the application of anammox processes to many types of industrial wastewater treatment.

    DOI

  • Identification of the Bacterial Community Involved in Methane-Dependent Denitrification in Activated Sludge Using DNA Stable-Isotope Probing

    T. Osaka, Y. Ebie, S. Tsuneda, Y Inamori

    FEMS Microbiol. Ecology   64 ( 3 ) 494 - 506  2008年05月

  • DNA microarray mediated transcriptional profiling of Nitrosomonas europaea in response to linear alkylbenzene sulfonates

    Hidetoshi Urakawa, Junpei Matsumoto, Kazuho Inaba, Satoshi Tsuneda

    FEMS MICROBIOLOGY LETTERS   282 ( 2 ) 166 - 173  2008年05月  [査読有り]

     概要を見る

    Linear alkylbenzene sulfonates (LAS) constitute, quantitatively, the most important group of synthetic surfactants used today. We studied the gene expression of Nitrosomonas europaea in response to LAS using a DNA microarray because ammonia-oxidizers are thought to be more sensitive to LAS than other microorganisms. Our objective was to elucidate which genes are expressed for N. europaea in response to LAS exposure. Microarray analysis and real-time PCR assay revealed that c. 30 genes were significantly expressed after LAS exposure, in particular genes associated with energy production and conversion. Our findings demonstrate that physical disruption of membrane structures, which contain enzymes associated with energy production and conversion, might be an important explanation for the high sensitivity of N. europaea to LAS exposure.

    DOI

  • Rhodamine-based fluorogenic probe for imaging biological thiol

    Aya Shibata, Kazuhiro Furukawa, Hiroshi Abe, Satoshi Tsuneda, Yoshihiro Ito

    BIOORGANIC & MEDICINAL CHEMISTRY LETTERS   18 ( 7 ) 2246 - 2249  2008年04月  [査読有り]

     概要を見る

    We have developed a new fluorescent probe for biological thiol. The probe was synthesized by the modi. cation of the 2,4-dinitrobenzenesulfonyl group with rhodamine 110. The selective detection of thiol species such as cysteine or glutathione was achieved in biological conditions. Moreover, the probe was successfully applied to the imaging of thiol species in living human cells. (C) 2008 Elsevier Ltd. All rights reserved.

    DOI

  • Retrieval of entire genes from environmental DNA by inverse PCR with pre-amplification of target genes using primers containing locked nucleic acids

    Kazutaka Yamada, Takeshi Terahara, Shinya Kurata, Toyokazu Yokomaku, Satoshi Tsuneda, Shigeaki Harayama

    ENVIRONMENTAL MICROBIOLOGY   10 ( 4 ) 978 - 987  2008年04月  [査読有り]

     概要を見る

    We had been unsuccessful to amplify desired nucleotide sequences from various environmental DNA samples by using the inverse polymerase chain reaction (IPCR) technique, most probably because the copy numbers of target DNA sequences had been quite low. To enrich the target DNA sequences prior to IPCR, a rolling-circle amplification was used with a site-specific primer containing locked nucleic acids (LNAs). This pre-amplified IPCR (PAI-PCR) method increased the sensitivity of PCR almost 10 000 times compared with the standard IPCR in model experiments using Escherichia coli. We then applied the PAI-PCR method to isolate glycosyl hydrolase genes from DNAs extracted from vermiform appendixes of horses and termite guts. The flanking sequences of the target genes were amplified and cloned successfully using PAI-PCR, whereas standard IPCR resulted in no amplification.

    DOI

  • 微生物固定化のための膜の改質と水処理分野への適用

    常田聡, 寺田昭彦

    膜   33 ( 2 ) 54 - 62  2008年03月

  • Novel nitritation process using heat-shocked nitrifying bacteria entrapped in gel carriers

    Kazuichi Isaka, Tatsuo Sumino, Satoshi Tsuneda

    PROCESS BIOCHEMISTRY   43 ( 3 ) 265 - 270  2008年03月  [査読有り]

     概要を見る

    Nitritation (ammonium being oxidized to nitrite) is a cost-effective method for treating wastewater having high ammonium concentrations or low ON ratios. We developed a novel nitritation process based on the observation that nitrite-oxidizing bacteria (NOB) in sewage sludge can be killed by heat shock, but ammonium-oxidizing bacteria (AOB) may survive. The effects of maximum heat-shock temperature and heat-shock duration on populations of AOB and NOB in gel carriers were measured. No NOB were detected after a heat-shock treatment higher than 60 degrees C for 20 min. However, the population of AOB continued to exist at above 10(8) MPN/mL-carrier even after heat shock at 80 degrees C for 1 h. To evaluate the nitritation performance, continuous feeding tests were conducted using heat-shocked gel carriers treated at three temperatures. Stable nitritation was observed for 49 days when gel carriers were heat shocked at 60-90 degrees C for 1 h. However, because nitrate production, i.e., nitratation, was observed after 77 days, the gel carriers were heat shocked again. Consequently, nitratation stopped immediately and nitritation restarted after 14 days. These results clearly show that this technique is effective for suppressing nitratation. (C) 2007 Elsevier Ltd. All rights reserved.

    DOI

  • Low temperature decreases the phylogenetic diversity of ammonia-oxidizing archaea and bacteria in aquarium biofiltration systems

    Hidetoshi Urakawa, Yoshiyuki Tajima, Yoshiyuki Numata, Satoshi Tsuneda

    APPLIED AND ENVIRONMENTAL MICROBIOLOGY   74 ( 3 ) 894 - 900  2008年02月  [査読有り]

     概要を見る

    The phylogenetic diversity and species richness of ammonia-oxidizing archaea (AOA) and bacteria (AOB) were examined with aquarium biofiltration systems. Species richness, deduced from rarefaction analysis, and diversity indices indicated that the phylogenetic diversity and species richness of AOA are greater than those of AOB; the diversity of AOA and of AOB is minimized in cold-water aquaria. This finding implies that temperature is a key factor influencing the population structure and diversity of AOA and AOB in aquarium biofiltration systems.

    DOI

  • Estimation of single-nucleotide polymorphism allele frequency by alternately binding probe competitive polymerase chain reaction

    Naohiro Noda, Hidenori Tani, Nao Morita, Shinya Kurata, Kazunori Nakamura, Takahiro Kanagawa, Satoshi Tsuneda, Yuji Sekiguchi

    ANALYTICA CHIMICA ACTA   608 ( 2 ) 211 - 216  2008年02月  [査読有り]

     概要を見る

    Estimation of single-nucleotide polymorphism (SNP) allele frequency in pooled DNA samples is a promising approach to clarify the relationships between SNPs and diseases. Here, we present a simple, accurate, and cost-effective method for estimating SNP allele frequency, called alternately binding probe (ABProbe) competitive polymerase chain reaction (ABC-PCR) that entails no expensive devices for real-time fluorescence measurement and complex post-PCR steps. We prepared DNA pools of PCR products derived from homozygous samples of three different SNPs (ALDH2, GNB3, and HTR2A) in different portions, and the allele frequencies of these samples were estimated by ABC-PCR. Two alleles were coamplified by PCR with a fluorescent probe that binds to either alleles, and then fluorescence intensity was measured using a simple fluorometer. The ratio of the two alleles was calculated from the fluorescence intensity of the probe at the end-point. The estimated allele frequencies strongly correlated to the expected ratios for all three SNPs with high accuracy. When the allele frequencies were more than 5%, the relative standard deviations (R.S.D.s) of ABC-PCR were less than 20%. Moreover, we also confirmed that this method was applicable to SNP genotyping. (c) 2007 Elsevier B.V. All rights reserved.

    DOI

  • SBMBfRによる生物学的窒素・リン除去技術の開発と低C/N比排水への適用性評価

    伊藤 潤平, 寺田 昭彦, 松本 慎也, 常田 聡

    化学工学会 研究発表講演要旨集   2008   723 - 723  2008年

    DOI CiNii

  • Rapid DNA chemical ligation for amplification of RNA and DNA signal

    Hiroshi Abe, Yuko Kondo, Hiroshi Jinmei, Naoko Abe, Kazuhiro Furukawa, Atsushi Uchiyama, Satoshi Tsuneda, Kyoko Aikawa, Isamu Matsumoto, Yoshihiro Ito

    BIOCONJUGATE CHEMISTRY   19 ( 1 ) 327 - 333  2008年01月  [査読有り]

     概要を見る

    Enzymatic ligation methods are useful in the diagnostic detection of DNA sequences. Here, we describe the investigation of nonenzymatic phosphorothioate-iodoacetyl DNA chemical ligation as a method for the detection and identification of RNA and DNA. The specificity of ligation on the DNA target is shown to allow the discrimination of a single point mutation with a drop in the ligation yield of up to 16.1-fold. Although enzymatic ligation has very low activity for RNA targets, this reaction is very efficient for RNA targets. The speed of the chemical ligation with an RNA target achieves a 70% yield in 5 s, which is equal to or better than that of ligase-enzyme-mediated ligation with a DNA target. The reaction also exhibits a significant level of signal amplification under thermal cycling in periods as short as 100-120 min, with the RNA or DNA target acting in a catalytic way to ligate multiple pairs of probes.

    DOI

  • Real-time control strategy for simultaneous nitrogen and phosphorus removal using aerobic granular sludge

    N. Kishida, S. Tsuneda, Y. Sakakibara, J. H. Kim, R. Sudo

    WATER SCIENCE AND TECHNOLOGY   58 ( 2 ) 445 - 450  2008年  [査読有り]

     概要を見る

    To achieve stable and simultaneous removal of nitrogen and phosphorus using aerobic granular sludge in a sequencing batch reactor, a real-time control strategy was established, where time derivatives of electric conductivity (EC) and pH were monitored to facilitate the determinations of ends of phosphate release, nitrification and denitrification as well as corresponding optimum time-lengths of anaerobic, oxic, and anoxic phases in treatment cycles. Although biomass concentration in a reactor drastically fluctuated at the startup period because of very short sludge settling time for the formation of aerobic granular sludge, cycle length for proper treatment was automatically adjusted in this control system. Even when characteristics of influent wastewater markedly fluctuated, stable nitrogen and phosphorus removal was successfully attained both before and at pseudo-steady-state. Effluent concentrations of NH(4)-N, NO(x)-N and PO(4)-P were always lower than 0.3 mg/L. On the other hand, when time lengths of the anaerobic/oxic/anoxic phases were fixed, stable nitrogen and phosphorus removal was not accomplished. Therefore, it is clear that the designed control system is very effective to obtain stable treatment performance in simultaneous nitrogen and phosphorus removal by aerobic granular sludge.

    DOI

  • Tertiary treatment of domestic wastewater using zeolite ceramics and aquatic plants

    Y. Kimochi, T. Masada, Y. Mikami, S. Tsuneda, R. Sudo

    WATER SCIENCE AND TECHNOLOGY   58 ( 4 ) 847 - 851  2008年  [査読有り]

     概要を見る

    In this study, we examined tertiary treatment of domestic wastewater using zeolite ceramics and aquatic plants, especially reeds, Phragmites australis. The experiment was made at real domestic wastewater treatment facilities, and comparison of treatment performance was made between the method with zeolite ceramics and that with pebble stones as conventional way. SEM observation of the ceramics&apos; surface was also made to examine its possibility as the habitat of bacteria. The results obtained are as follows. Through the tertiary treatment experiment, it was suggested that the water purification system with zeolite ceramics and reeds could keep higher nitrogen removal efficiency for a long time. Zeolite ceramics would be useful when nitrogen compound, NH(4)-N in particular, in the influent was higher. Under SEM observation, bacteria-like objects were observed on the ceramics&apos; surface. Appropriate operation and maintenance would be needed to keep long-term performance of both the NH(4)(+) absorption and nitrogen removal with use of zeolite ceramics.

    DOI

  • Microbial community of anammox bacteria immobilized in polyethylene glycol gel carrier

    Y. Date, K. Isaka, T. Sumino, S. Tsuneda, Y. Inamori

    WATER SCIENCE AND TECHNOLOGY   58 ( 5 ) 1121 - 1128  2008年  [査読有り]

     概要を見る

    Anaerobic ammonium oxidation (anammox) is a recently discovered microbial pathway in the biological nitrogen cycle and a new cost-effective way to remove ammonium from wastewater. We have so far developed new immobilization technique that anammox bacteria entrapped in polyethylene glycol (PEG) gel carrier. However, fate and behavior of anammox bacteria in a gel carrier is not well understood. In the present study, we focused on the population changes of anammox bacteria in a gel carrier. Three specific primer sets were designed for real-time PCR. For quantification of anammox bacteria in a gel carrier, real-time PCR was performed. The anammox bacteria related to HPT-WU-N03 clone were increased the rate in anammox population, and found to be a major population of anammox bacteria in a gel carrier. Furthermore, from the results of nitrogen removal performance and quantification of anammox bacteria, the correlation coefficient between copy numbers of anammox bacteria and nitrogen conversion rate was calculated as 0.947 in total anammox population. This is the first report that population changes of anammox bacteria immobilized in a gel carrier were evaluated.

    DOI

  • Design of polymer brushes for immobilizing enzymes onto hollow fiber micropores in organic media reaction

    Muneharu Goto, Tokie Okubo, Hidetaka Kawakita, Kazuya Uezu, Satoshi Tsuneda, Kyoichi Saito, Masahiro Goto, Masao Tamada, Takanobu Sugo

    Biochemical Engineering Journal   37 ( 2 ) 159 - 165  2007年11月  [査読有り]

     概要を見る

    To immobilize lipase for enzymatic reactions in organic solvent, various functional [epoxy (GMA-fiber), hydroxyl (OH-fiber) or diethyl amino (DEA-fiber)] groups were introduced onto porous hollow-fiber membranes by radiation-induced graft polymerization of glycidyl methacrylate and chemical modification. Lipase from Candida rugosa was immobilized on polymer brushes by permeation of lipase. The activities of immobilized lipase were measured by esterification reactions between lauric acid and benzyl alcohol in isooctane. The activity of immobilized lipase on GMA-fibers, DEA-fibers and OH-fibers was 0.70 mol/(h kg-lipase), 0.50 mol/(h kg-lipase), and 2.45 mol/(h kg-lipase), respectively. Immobilized lipase on DEA-fibers or OH-fibers was reused three times after it was used in the batch reactor for 24 h. It was found that lipase activity showed no signs of denaturation. However, when native lipase was used, lipase activity remarkably decreased after reusing. © 2007 Elsevier B.V. All rights reserved.

    DOI

  • Adsorption of bovine serum albumin to a polymer brush prepared by atom-transfer radical polymerization in a porous inorganic membrane

    Hidetaka Kawakita, Hiroyasu Masunaga, Kanako Nomura, Kazuya Uezu, Isamu Akiba, Satoshi Tsuneda

    Journal of Porous Materials   14 ( 4 ) 387 - 391  2007年11月  [査読有り]

     概要を見る

    Protein adsorption was performed by a polymer brush prepared by atom-transfer radical polymerization (ATRP) to a porous inorganic membrane. The porous inorganic membrane, Shirasu Porous Glass made from silica, was modified with a halogen-containing compound to bind the active species for the polymerization. Glycidyl methacrylate was polymerized from the halogen compound by ATRP for a prescribed time, and subsequently chemically modified. The progression of the chemical modification allowed the membrane to lower the phosphate-buffer flux of the porous membrane due to the attachment of the polymer brush. Bovine serum albumin (BSA), as a model protein, was adsorbed at 12 mg per gram of the membrane in permeating BSA solution through the polymer-brush-attached porous membrane. © 2006 Springer Science+Business Media, LLC.

    DOI

  • 細胞内遺伝子発現検出用の蛍光バイオプローブの設計と合成

    阿部洋, 古川和寛, 常田聡, 伊藤嘉浩

    蛋白質拡散酵素   52 ( 13 ) 1619 - 1624  2007年10月

  • リン回収技術の現状と将来展望

    蛯江美孝, 近藤貴志, 徐開欽, 常田聡, 稲森悠平

    再生と利用   30 ( 117 ) 6 - 10  2007年10月

  • Nitrification of landfill leachate using immobilized nitrifying bacteria at low temperatures

    Kazuichi Isaka, Sachiko Yoshie, Tatsuo Sumino, Yuhei Inamori, Satoshi Tsuneda

    BIOCHEMICAL ENGINEERING JOURNAL   37 ( 1 ) 49 - 55  2007年10月  [査読有り]

     概要を見る

    A technology to achieve stable and high rates of nitrification of landfill leachate at low temperatures has been desired. Nitrifying bacteria entrapped in a polyethylene glycol (PEG) gel carrier produced high nitrification rates of 0.71 kg N/m(3) /day at 10 degrees C for more than I year. As a characteristic of nitrification, ammonium nitrogen at 16-35 mg/L remained in effluent water irrespective of nitrogen load and nitrite accumulation was observed. Batch experiments clearly showed that the relationship between ammonium concentration and ammonium removal rate followed a Monod-type equation. It was also revealed that ammonium-oxidizing bacteria cultivated in a gel carrier had a low affinity for ammonium, leading to incomplete nitrification. Moreover, it was suggested that the remaining ammonium in the reactor produced free ammonium, which inhibited the activities of nitrite-oxidizing bacteria. Thus, only nitritation was observed. Molecular biological methods, such as denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH), revealed that Nitrosomonas sp. was the dominant ammonium-oxidizing bacteria in the gel carrier at low temperature. (C) 2007 Elsevier B.V. All rights reserved.

    DOI

  • Modeling of membrane-aerated biofilm: Effects of C/N ratio, biofilm thickness and surface loading of oxygen on feasibility of simultaneous nitrification and denitrification

    Shinya Matsumoto, Akihiko Terada, Satoshi Tsuneda

    BIOCHEMICAL ENGINEERING JOURNAL   37 ( 1 ) 98 - 107  2007年10月  [査読有り]

     概要を見る

    A multipopulation model of a membrane-aerated biofilm (MAB) considering heterotrophic bacteria (HB), ammonia-oxidizing bacteria (AOB), and nitrite-oxidizing bacteria (NOB) was constructed with the simulation software AQUASIM 2.1 to corroborate the process concept of the membrane-aerated biofilm reactor (MABR) and to reveal an operational range for high chemical oxygen demand (COD) and nitrogen removal efficiencies. The modeling results confirm that simultaneous nitrification and denitrification (SND) is feasible in the MAB but not in a top-down aerated biofilm (conventional biofilm) due to the absence of oxygen for AOB and NOB. The model precisely predicts the COD, NH4+-N, and T-N removal efficiencies and determines operating parameters like COD/nitrogen (C/N) ratio, biofilm, thickness and surface loading of oxygen, which significantly affect SND efficiency. High nitrogen removal efficiency (more than 70%) is attained at ranges of C/N ratio from 3.0 to 5.25 and of biofilm thickness from 600 to 1200 mu m. In addition, it was clearly demonstrated that nitrogen removal not via nitrate but via nitrite could be achieved by controlling the relative surface loadings of oxygen and ammonia, supporting the feasibility of short-cut SND with MABs. (C) 2007 Elsevier B.V. All rights reserved.

    DOI

  • Ammonium removal performance of anaerobic ammonium-oxidizing bacteria immobilized in polyethylene glycol gel carrier - Anammox bacteria immobilized in gel carrier

    Kazuichi Isaka, Yasuhiro Date, Tatsuo Sumino, Satoshi Tsuneda

    APPLIED MICROBIOLOGY AND BIOTECHNOLOGY   76 ( 6 ) 1457 - 1465  2007年10月  [査読有り]

     概要を見る

    Anaerobic ammonium-oxidizing (anammox) bacteria were immobilized in polyethylene glycol gel carriers. A small amount of seed sludge [0.24% (w/v)] was entrapped in the carriers, and continuous feeding tests were performed. Nitrogen removal activity increased gradually, reaching 3.7 kg N/m(3) stop reactor per day on day 67. The average of nitrogen conversion rate was calculated as 3.4 kg N/m(3) reactor per day. Microscopic examination clearly showed that small red clusters formed in the gel carrier. Moreover, fluorescence in situ hybridization analysis revealed that these clusters consisted of anammox bacteria. From real-time polymerase chain reaction analysis, the growth of anammox bacteria in the gel carriers was clearly shown by increased concentration of 16S rRNA gene of planctomycete from 4.3 x 10(8) to 4.2 x 10(9) copies/ml between days 41 and 55. To determine the effects of inoculation on the start-up of the reactor, the amount of seed sludge in the gel carrier was varied and it was found that the start-up period could be reduced to as little as 25 days when a sludge concentration of 1.4% (w/v) was used. This is the first report of successful immobilization and cultivation of anammox bacteria in a gel carrier.

    DOI

  • Calibration-Curve-Free Quantitative PCR: A Quantitative Method for Specific Nucleic Acid Sequences without Using Calibration Curves

    H. Tani, T. Kanagawa, N. Morita, S. Kurata, K. Nakamura, S. Tsuneda, N. Noda

    Anal. Biochem.   369 ( 1 ) 105 - 111  2007年09月

  • Analysis of the Relationship between Ammonia Oxidizing Bacterial Populations and Nitrification Efficiency in Full-Scale Advanced Johkasou Using Different Structured Carriers by Real-Time PCR

    G. Nakagawa, Y. Ebie, S. Tsuneda, M. Matsumura, Y. Inamori

    Jpn. J. Water Treatment Biol.   43 ( 3 ) 143 - 149  2007年09月

  • Technique for quantitative detection of specific DNA sequences using alternately binding quenching probe competitive assay combined with loop-mediated isothermal amplification

    Hidenori Tani, Tatsuya Teramura, Ken Adachi, Satoshi Tsuneda, Shinya Kurata, Kazunori Nakamura, Takahiro Kanagawa, Naohiro Noda

    ANALYTICAL CHEMISTRY   79 ( 15 ) 5608 - 5613  2007年08月  [査読有り]

     概要を見る

    We describe a novel technique for a simple, rapid, and reliable quantitative detection of specific DNA sequences using an alternately binding quenching probe (AB-QProbe) that binds to either the gene of interest (target) or an internal standard (competitor) in combination with loop-mediated isothermal amplification (1,AMP). The AB-QProbe is a singly labeled oligonucleotide bearing a fluorescent dye at the 5' end. The fluorescence intensity of the AB-QProbe reflects the ratio of the LAMP products from the target and competitor. We amplified the target and competitor by 1,AMP under isothermal conditions with high specificity, efficiency, and rapidity and calculated the starting quantity of the target from the fluorescence intensities at the beginning and end of LAMP. We call this technique alternately binding quenching probe competitive LAMP (ABC-LAMP). We quantified amoA, which encodes the ammonia-oxidizing enzyme in environmental bacteria, as a model target by ABC-LAMP, real-time PCR, and real-time turbidimetry of LAMP. By comparison, the accuracy of ABC-LAMP was found to be similar to that of real-time PCR. Moreover, ABC-LAMP enables the accurate quantification of DNA in the presence of DNA amplification inhibitors such as humic acid, urea, and Triton X-100 that compromise the values measured by real-time PCR and real-time turbidimetry of LAMP.

    DOI

  • Diversity of nitrite reductase genes in "Candidatus Accumulibacter phosphatis"-Dominated cultures enriched by flow-cytometric sorting

    Ryuki Miyauchi, Kazuma Oki, Yoshiteru Aoi, Satoshi Tsuneda

    APPLIED AND ENVIRONMENTAL MICROBIOLOGY   73 ( 16 ) 5331 - 5337  2007年08月  [査読有り]

     概要を見る

    "Candidatus Accumullibacter phosphatis" is considered a polyphosphate-accumulating organism (PAO) though it has not been isolated yet. To reveal the denitrification ability of this organism, we first concentrated this organism by flow cytometric sorting following fluorescence in situ hybridization (FISH) using specific probes for this organism. The purity of the target cells was about 97% of total cell count in the sorted sample. The PCR amplification of the nitrite reductase genes (nirK and nirS) from unsorted and sorted cells was performed. Although nirK and nirS were amplified from unsorted cells, only nirS was detected from sorted cells, indicating that "Ca. Accumulibacter phosphatis" has nirS. Furthermore, nirS fragments were cloned from unsorted (Ba clone library) and sorted (Bd clone library) cells and classified by restriction fragment length polymorphism analysis. The most dominant clone in clone library Ba, which represented 62% of the total number of clones, was not found in clone library Bd. In contrast, the most dominant clone in clone library Bd, which represented 59% of the total number of clones, represented only 2% of the total number of clones in clone library Ba, indicating that this clone could be that of "Ca. Accumullibacter phosphatis." The sequence of this nirS clone exhibited less than 90% similarity to the sequences of known denitrifying bacteria in the database. The recovery of the nirS genes makes it likely that "Ca. Accumulibacter phosphatis" behaves as a denitrifying PAO capable of utilizing nitrite instead of oxygen as an electron acceptor for phosphorus uptake.

    DOI

  • シミュレーションによるバイオフィルムシステム解析の進展

    松本慎也, 青井議輝, 常田聡

    ケミカルエンジニヤリング   52 ( 5 ) 359 - 363  2007年05月

  • Redox-stratification controlled biofilm (ReSCoBi) for completely autotrophic nitrogen removal: The effect of co- versus counter-diffusion on reactor performance

    Akihiko Terada, Susanne Lackner, Satoshi Tsuneda, Barth F. Smets

    BIOTECHNOLOGY AND BIOENGINEERING   97 ( 1 ) 40 - 51  2007年05月  [査読有り]

     概要を見る

    A multi-population biofilm model for completely autotrophic nitrogen removal was developed and implemented in the simulation program AQUASIM to corroborate the concept of a redox-stratification controlled biofilm (ReSCoBi). The model considers both counter- and co-diffusion, oxygen is supplied through a gas-permeable membrane that supports the biofilm while ammonia (NH4+) is supplied form the bulk liquid. On the contrary, in the co-diffusion biofilm, both oxygen and HH4+ are supplied from the bulk liquid. Results of the model revealed a clear stratification of microbial activities in both of the biofilms, the resulting chemical profiles, and the obvious effect of the relative surface loadings of oxygen and NH4+ (J(O2)/J(NH4+)) on the reactor performances. Steady-state biofilm thickness had a significant but different effect on T-N removal for co- and counter-diffusion biofilms: the removal efficiency in the counter-diffusion biofilm geometry was superior to that in the co-diffusion counterpart, within the range of 450-1,400 mu m; however, the efficiency deteriorated with a further increase in biofilm thickness, probably because of diffusion limitation of NH4+. Under conditions of oxygen excess (J(O2)/J(NH4)(+) &gt; 3.98), almost all NH4+ was consumed by aerobic ammonia oxidation in the co-diffusion biofilm, leading to poor performance, while in the counter-diffusion biofilm, T-N removal efficiency was maintained because of the physical location of anaerobic ammonium oxidiers near the bulk liquid. These results clearly reveal that counter-diffusion biofilms have a wider application range for autotrophic T-N removal than co-diffusion biofilms.

    DOI

  • RNA microarray for estimating relative abundance of 16S rRNA in microbial communities

    Tatsuhiko Hoshino, Kazuhiro Furukawa, Satoshi Tsuneda, Yuhei Inamori

    JOURNAL OF MICROBIOLOGICAL METHODS   69 ( 2 ) 406 - 410  2007年05月  [査読有り]

     概要を見る

    We developed an RNA microarray protocol in which total RNA frorn a microbial community was attached to a slide glass, and rRNA was detected by fluorescently labeled oligonucleotide probes. The RNA microar-ray requires only 4 h for hybridization and enables double staining and estimating relative abundance of rRNA. (C) 2007 Elsevier B.V. All rights reserved.

    DOI

  • High nitrogen removal performance at moderately low temperature utilizing anaerobic ammonium oxidation reactions

    Kazuichi Isaka, Tatsuo Sumino, Satoshi Tsuneda

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   103 ( 5 ) 486 - 490  2007年05月  [査読有り]

     概要を見る

    High rates of nitrogen removal from wastewater have been reported using anammox bacteria at temperatures around 37 C, but not at moderately low temperatures. In this study, nitrogen removal performance of an anaerobic biological filtrated (ABF) reactor, filled with porous polyester nonwoven fabric carriers as a fixed bed for anammox bacteria, was tested at 37 C and at moderately low temperature (20-22 degrees C). To attain higher nitrogen removal performance, effects of influent nitrogen concentrations and hydraulic retention time (HRT) on nitrogen removal rates were investigated. Nitrogen removal rate increased with influent ammonium and nitrite concentrations, resulting in a removal rate of 3.3 kg-N/m(3)/d on day 32 for an HRT of 180 min at 37 degrees C. However, influent nitrite concentrations greater than 280 mg/l inhibited anammox activity. Therefore, the influent nitrite concentration was adjusted to be below 280 mg/l, and high-loading tests were performed for a shorter HRT. As a result, a nitrogen conversion rate of 11.5 kg-N/m(3)/d was achieved. Moreover, to evaluate long-term anammox activity at moderately low temperatures, ABF reactors were operated for 446 d. Anammox activity could be maintained at 20-22 degrees C, and stable nitrogen removal performance was observed. Furthermore, high nitrogen conversion rate of 8.1 kg-N/m(3)/d was attained. These results clearly show that an appropriate nitrite concentration in the influent and a shorter HRT resulted in high nitrogen conversion rates. The nitrogen removal performance we obtained at moderately low temperatures will open the door for application of anammox processes to many types of industrial wastewater treatment.

    DOI

  • ゼオライト成形体の導入による高機能窒素除去型の植栽水質浄化法の開発

    木持謙, 正田武則, 三上恭弘, 常田聡

    月刊「水」   May-49 ( 700 ) 27 - 32  2007年04月

  • Determination of Polyphosphate-Accumulating Organisms Activity in Enhanced Biological Phosphorus Removal Using Conventional Methods and Microautoradiograly-FISH

    T. Kondo, Y. Ebie, S. Tsuneda, Y. Inamori

    Jpn. J. Water Treatment Biol.   43 ( 1 ) 19 - 29  2007年03月

  • Characterization of the High-Density Bacteria in Biological Phosphorus Removal Process by Using Buoyant Density Separation

    T. Kondo, Y. Ebie, S. Tsuneda, Y. Inamori

    Jpn. J. Water Treatment Biol.   43 ( 1 ) 51 - 62  2007年03月

  • Quantitative method for specific nucleic acid sequences using competitive polymerase chain reaction with an alternately binding probe

    Hidenori Tani, Takahiro Kanagawa, Shinya Kurata, Tatsuya Teramura, Kazunori NakamuraO, Satoshi Tsuneda, Naohiro Noda

    ANALYTICAL CHEMISTRY   79 ( 3 ) 974 - 979  2007年02月  [査読有り]

     概要を見る

    We have developed a simple, cost-effective, and accurate method for the quantification of specific nucleic acid sequences by the combined use of competitive PCR and a sequence-specific fluorescent probe that binds to either the gene of interest (target) or internal standard (competitor), referred to as alternately binding probe (ABProbe). In this method, the target and competitor were coamplified with the ABProbe, and then the fluorescence intensity was measured. The ratio of the target to the competitor can be calculated from the fluorescence intensity of the ABProbe using fluorescence quenching and fluorescence resonance energy transfer, that is, the starting quantity of the target is successfully calculated by end-point fluorescence measurement. Therefore, this method eliminates the complex post-PCR steps and expensive devices for real-time fluorescence measurement. We called this method alternately binding probe competitive PCR (ABC-PCR). We quantified amoA as a model target by ABC-PCR and real-time PCR. By comparison, the sensitivity, accuracy, and precision of ABC-PCR were similar to those of real-time PCR. Moreover, ABC-PCR was able to correctly quantify DNA even when PCR was inhibited by humic acid; therefore, this method will enable accurate DNA quantification for biological samples that contain PCR inhibitors.

    DOI

  • Use of real-time PCR to examine the relationship between ammonia oxidizing bacterial populations and nitrogen removal efficiency in a small decentralized treatment system 'Johkasou'

    G. Nakagawa, Y. Ebie, S. Tsuneda, M. Matsumura, Y. Inamori

    WATER SCIENCE AND TECHNOLOGY   55 ( 7 ) 203 - 210  2007年  [査読有り]

     概要を見る

    The aim of this study was to examine the relationship between ammonia oxidizing bacterial populations and biological nitrogen removal in a small on-site domestic wastewater treatment system "Johkasou". The population dynamics of ammonia oxidizing bacteria (AOB) in six full-scale advanced Johkasous was surveyed using real-time PCR assay over a period of one year. These Johkasous were selected to compare the AOB:populations in different treatment performance. When the effluent NH4-N concentration was higher than 2 mg L-1, it was difficult to meet the effluent standard of advanced Johkasous (T-N 10 mg L-1). In contrast, the nitrogen removal efficiency was hardly affected by nitrite oxidation and denitrification in these systems. In other words, ammonia oxidation was a rate-limiting step. Furthermore, we focused on the relationship between NH4-N loading per AOB cell and nitrogen removal. Real time PCR monitoring results demonstrated that it is important to regulate NH4-N loading per AOB cell below 210 pg cell(-1) day(-1) to meet the effluent standard of advanced Johkasou. It is considered that NH4-N loading per AOB cell is a useful parameter for determining suitable nitrogen loading and small decentralized system design.

    DOI

  • Experimental and simulation analysis of community structure of nitrifying bacteria in a membrane-aerated biofilm

    S. Matsumoto, A. Terada, Y. Aoi, S. Tsuneda, E. Alpkvist, C. Picioreanu, M. C. M. van Loosdrecht

    WATER SCIENCE AND TECHNOLOGY   55 ( 8-9 ) 283 - 290  2007年  [査読有り]

     概要を見る

    Until now, only few attempts have been made to assess biofilm models simulating microenvironments in a biofilm. As a first step, we compare the microenvironment observed in a membrane aerated biofilm (MAB) to that derived from a two-dimensional computational model with individual ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) embedded in a continuum EPS matrix. Gradients of oxygen were determined by means of microelectrodes. The change in nitrifying bacterial populations with the biofilm depth was quantified using fluorescence in situ hybridization (FISH) in combination with a confocal laser scanning microscopy (CLSM). Microelectrode measurements revealed that oxic and anoxic or anaerobic regions exist within the MAB. The oxygen profile predicted by the model showed good agreement with that obtained by microelectrode measurements. The oxic part of the biofilm was dominated by NSO190 probe-hybridized AOB, which formed relatively large clusters of cells directly on the membrane surface, and by the NOB belonging to genus Nitrobacter sp. On the other hand, NOB belonging to genus Nitrospira sp. were abundant at the oxic-anoxic interface. The model prediction regarding AOB and Nitrobacter sp. distribution was consistent with the experimental counterpart. Measurements of AOB cluster size distribution showed that colonies are slightly larger adjacent to the membrane than at the inner part of the biofilm. The sizes predicted by the current model are larger than those obtained in the experiment, leading to the arguments that some factors not contained in the model would affect the cluster size.

    DOI

  • Direct profiling of rRNA in saline wastewater treatment samples using an oligonucleotide Microarray

    Hidetoshi Urakawa, Junpei Matsumoto, Tatsuhiko Hoshino, Satoshi Tsuneda

    MICROBES AND ENVIRONMENTS   22 ( 2 ) 116 - 122  2007年  [査読有り]

     概要を見る

    Fifteen oligonucleotide probes, targeting a broad range of microorganisms, were spotted on a DNA microarray. Specificity and reproducibility were evaluated using fluorescently labeled rRNA from 16 bacterial and eukaryal strains. The oligonucleotide microarray was then used to analyze activated sludge samples of saline industrial wastewater in which microbial communities had been characterized previously using 16S rRNA clone libraries. The results obtained were partially consistent with the results of cloning, and demonstrate the possibility of using oligonucleotide microarrays for the monitoring and characterization of saline industrial wastewater populations.

  • Detection of Defluvicoccus-related glycogen-accumulating organisms in enhanced biological phosphorus removal processes

    Takashi Kondo, Yoshitaka Ebie, Satoshi Tsuneda, Yuhei Inamori

    MICROBES AND ENVIRONMENTS   22 ( 2 ) 190 - 195  2007年  [査読有り]

     概要を見る

    To distinguish subgroups of Defluvicoccus-related glycogen-accumulating organisms (Defluvicoccus-related G-bacteria), new oligonucleotide probes were designed. Two of these probes, DF636 and DF827, were used successfully to detect each subgroup of Defluvicoccus-related G-bacteria. The morphological differences in clusters and cells between the DF636- and DF827-binding cells were confirmed. Interestingly, DF636-binding cells showed autofluorescence under UV light. Additionally, auto fluorescence was observed in some alphaproteobacterial G-bacteria, which did not bind to any of the probes designed in this study. The results suggested that the Defluvicoccus-related G-bacteria consist of several physiologically different subspecies.

  • Psg18 is specifically expressed in follicle-associated epithelium

    Kazuya Kawano, Masashi Ebisawa, Koji Hase, Shinji Fukuda, Atsushi Hijikata, Sayaka Kawano, Yasuhiro Date, Satoshi Tsuneda, Kikuji Itoh, Hiroshi Ohno

    CELL STRUCTURE AND FUNCTION   32 ( 2 ) 115 - 126  2007年  [査読有り]

     概要を見る

    Pregnancy-specific glycoproteins (Psgs) secreted by the placenta regulate the immune system to ensure the survival of the fetal allograft by inducing IL-10, an anti-inflammatory cytokine. However, it is unknown whether Psgs are involved in more general aspects of immune response other than maternal immunity. Here, we report that Psg18 is highly expressed in the follicle-associated epithelium (FAE) overlaying Peyer's patches (PPs). Bioinformatics analysis with Reference Database for Immune Cells (RefDIC) as well as RT-PCR data demonstrated that Psg18 is exclusively expressed in FAE in adult mice, in contrast to other Psg family members that are either not expressed or only slightly expressed in FAE. Psg18 expression was observed in FAE of germ-free-conditioned mice, and was slightly upregulated after bacterial inoculation. In situ hybridization analysis revealed that Psg18 is widely expressed throughout FAE. Furthermore, Psg18 protein is deposited on the extracellular matrix in the subepithelial dome beneath FAE, where antigen-presenting cells accumulate. These results suggest that Psg18 is an FAE-specific marker protein that could promote interplay between FAE and immune cells in mucosa-associated lymphoid tissues.

  • 電気泳動による微生物固定化空間内の基質輸送の促進と脱窒反応の向上

    常田聡, 賀來周一, 林浩志, 大串聡, 寺田昭彦, 平田彰

    化学工学論文集   32 ( 6 ) 507 - 513  2006年12月

  • Effects of acetate and nitrite addition on fraction of denitrifying phosphate-accnmnlating organisms and nutrient removal efficiency in anaerobic/aerobic/anoxic process

    Koichi Soejima, Kazurna Oki, Akihiko Terada, Satoshi Tsuneda, Akira Hirata

    BIOPROCESS AND BIOSYSTEMS ENGINEERING   29 ( 5-6 ) 305 - 313  2006年12月  [査読有り]

     概要を見る

    The effects of acetate and nitrite on the performance of sequencing batch reactors (SBRs) employing an anaerobic/aerobic/anoxic (AOA) process were investigated. Three types of SBR operations were used: sodium acetate addition at the start of anoxic condition for heterotrophic denitrification (Type 1); sodium acetate addition at the start of aerobic condition for anoxic phosphate removal by denitrifying pbosphate-accumulating organisms (DNPAOs) (Type 2: conventional AOA process); and nitrite addition at the start of aerobic condition for inhibition of phosphate-accumulating organisms (PAOs) (Type 3). A track experiment shows that Type 2 led to the best performance of SBRs among the three types. An analysis by fluorescence in situ hybridization (FISH) revealed that nitrite addition decreased the ratio of PAOs with a decrease in phosphorus removal efficiency. The fraction of DNPAOs in Type 2 was the highest at 13%, indicating that Type 2 is suitable for the simultaneous nitrogen and phosphorus removal in the AOA process.

    DOI

  • Bacterial adhesion to and viability on positively charged polymer surfaces

    Akihiko Terada, Atsushi Yuasa, Takashi Kushimoto, Satoshi Tsuneda, Akio Katakai, Masao Tamada

    MICROBIOLOGY-SGM   152 ( 12 ) 3575 - 3583  2006年12月  [査読有り]

     概要を見る

    Secondary and tertiary amino groups were introduced into polymer chains grafted onto a polyethylene flat-sheet membrane to evaluate the effects of surface properties on the adhesion and viability of a strain of the Gram-negative bacterium Escherichia cofiand a strain of the Gram-positive bacterium Bacillus subtilis. The characterization of the surfaces containing amino groups, i.e. ethylamino (EA) and diethylamino (DEA) groups, revealed that the membrane potentials are proportional to amino-group densities and contact angle hysteresis. A high bacterial adhesion rate constant k was observed at high membrane potential, which indicates that membrane potential could be used as an indicator for estimating bacterial adhesion to the EA and DEA sheets, especially in B. subtilis. The bacterial adhesion rate constant of E coli markedly increased at a membrane potential higher than -7.8 mV, whereas that of B. subtilis increased at a membrane potential higher than -8.3 mV, at which the dominant effect on bacterial adhesion is expected to change. The viability experiments revealed that approximately 80 % of E coli cells adhering to the sheets with high membrane potential were inactivated after a contact time of 8 h, whereas 60 % of B. subtilis cells were inactivated. Furthermore, E coli viability significantly decreased at a membrane potential higher than -7.8 mV, whereas B. subtilis viability decreased as membrane potential increased, which reflects differences in cell wall structure between E coli and B. subtilis.

    DOI

  • 分離培養技術の進展

    青井議輝, 波多徹, 常田聡

    生物工学   84 ( 11 ) 444 - 447  2006年11月

  • 生物学的リン除去プロセスの最新動向

    近藤貴志, 常田聡

    化学工学   70 ( 11 ) 616 - 620  2006年11月

  • Real-Time Quantitative LAMP (Loop-Mediated Isothermal Amplification of DNA) as a Simple Method for Monitoring Ammonia-Oxidizing Bacteria

    Y. Aoi, M. Hosogai, S. Tsuneda

    J. Biotechnol.   125 ( 4 ) 484 - 491  2006年09月

  • Identification of Acetate- or Methanol-Assimilating Bacteria under Nitrate-Reducing Conditions by Stable-Isotope Probing

    T. Osaka, S. Yoshie, S. Tsuneda, A. Hirata, N. Iwami, Y Inamori

    Microbial Ecology   52 ( 2 ) 253 - 266  2006年09月

  • 好気性グラニュールを用いた水処理技術

    岸田直裕, 常田聡

    水処理技術   47 ( 8 ) 349 - 355  2006年08月

  • Rapid autohydrogenotrophic denitrification by a membrane biofilm reactor equipped with a fibrous support around a gas-permeable membrane

    A. Terada, S. Kaku, S. Matsumoto, S. Tsuneda

    BIOCHEMICAL ENGINEERING JOURNAL   31 ( 1 ) 84 - 91  2006年08月  [査読有り]

     概要を見る

    A hydrogen-based membrane biofilm reactor (MBfR), employing fibrous slag as a bacterial carrier, was developed for rapid and stable autohydrogenotrophic denitrification. This reactor allows hydrogen to be supplied through a gas-permeable membrane to the biofilm supported by fibrous slag. The estimation of hydrogen supply rate clearly demonstrated that hydrogen flux (J(H2)) is dependent on the gas pressure, leading to a possibility to control J(H2) by adjusting the pressure. A startup experiment to investigate denitrification rate with time clarified that denitrification rate of 4.35 g N/m(2)/day was achieved on day 10, exhibiting rapid startup for autohydrogenotrophic denitrification. Continuous denitrification experiment obviously indicated the effectiveness of the fibrous slag as a bacterial support; concretely, mean denitrification efficiency and rate after 70-day operation reached 99% and 6.58 g N/m(2)/day at a hydrogen pressure of 50 kPa, respectively, which results in the accomplishment of stable and high-speed denitrification. However, hydrogen utilization efficiency (HUE) was approximately 40%. This low efficiency allowed autotrophic sulfate-reducing bacteria (SRB) to grow in the fibrous-membrane matrix; eventually the RUE for sulfate reduction increased up to 28% on day 74. This result clearly indicates the significance of J(H2) control through the gas-permeable membrane for suppressing the occurrence of sulfate reduction. (c) 2006 Elsevier B.V. All rights reserved.

    DOI

  • Molecular analysis of halophilic bacterial community for high-rate denitrification of saline industrial wastewater

    Sachiko Yoshie, Hiroshi Makino, Hidenobu Hirosawa, Kosuke Shirotani, Satoshi Tsuneda, Akira Hirata

    APPLIED MICROBIOLOGY AND BIOTECHNOLOGY   72 ( 1 ) 182 - 189  2006年08月  [査読有り]

     概要を見る

    A denitrification system for saline wastewater utilizing halophilic denitrifying bacteria has not been developed so far. In this study, denitrification performance and microbial community under various saline conditions were investigated using denitrifying sludge acclimated under low-salinity condition for a few years as seed sludge. A continuous denitrification experiment showed that denitrification performance and microbial community at 10% salinity was higher than that at 1% salinity. The microbial community in the denitrification sludge that was acclimated under low salinity was monitored by terminal-restriction fragment length polymorphism (T-RFLP) analysis during acclimation to high-salinity condition. T-RFLP profiles and clone analysis based on 16S rRNA-encoding genes in the sludge of the denitrification system with 10% salinity indicated that the gamma-Proteobacteria, particularly Halomonas spp., were predominant species, suggesting that these bacterial members were possibly responsible for a high denitrification activity under high-salinity conditions. Furthermore, the investigation of denitrification performance under various saline conditions revealed that 4-10% salinity results in the highest denitrification rate, indicating that this salinity was optimal for predominant bacterial species to exhibit denitrification activity. These results indicate the possibility that an appropriate denitrification system for saline wastewater can be designed using acclimated sludge with a halophilic community.

    DOI

  • Highly sensitive real-time PCR assay for quantification of toxic cyanobacteria based on microcystin synthetase a gene

    Kazuhiro Furukawa, Naohiro Noda, Satoshi Tsuneda, Takeshi Saito, Tomoaki Itayama, Yuhei Inamori

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   102 ( 2 ) 90 - 96  2006年08月  [査読有り]

     概要を見る

    The presence of cyanobacterial bloom in water supply reservoirs can cause potential health hazards. In this study, we aimed at the quantification of microcystin-producing cyanobacteria based on the microcystin synthetase A (mcyA) gene using real-time PCR. To perform a highly sensitive real-time PCR assay, the novel primer MSR-2R was designed and a coprecipitation DNA extraction method was used in this study. Cyanobacterial cells could be collected efficiently by coprecipitation with other bacteria suspended in solution even in the case of low concentrations of cyanobacteria. The detection limit of the method was found to be 8.8 cells per reaction. When cyanobacterial growth was monitored in pure culture, the cell concentration determined by real-time PCR positively correlated with the cell concentration determined from direct microscopic count. Furthermore, we could detect and quantify the mcyA gene in lake water samples using real-time PCR. It was concluded that the quantification of the mcyA gene based on real-time PCR is a powerful tool for the rapid quantification of microcystin-producing cyanobacteria in environmental samples.

    DOI

  • Anaerobic/oxic/anoxic granular sludge process as an effective nutrient removal process utilizing denitrifying polyphosphate-accumulating organisms

    Naohiro Kishida, Juhyun Kim, Satoshi Tsuneda, Ryuichi Sudo

    WATER RESEARCH   40 ( 12 ) 2303 - 2310  2006年07月  [査読有り]

     概要を見る

    In a biological nutrient removal (BNR) process, the utilization of denitrifying polyphosphate-accumulating organisms (DNPAOs) has many advantages such as effective use of organic carbon substrates and low sludge production. As a suitable process for the utilization of DNPAOs in BNR, an anaerobic/oxic/anoxic granular sludge (AOAGS) process was proposed in this study. in spite of performing aeration for nitrifying bacteria, the AOAGS process can create anaerobic/anoxic conditions suitable for the cultivation of DNPAOs because anoxic zones exist inside the granular sludge in the oxic phase. Thus, DNPAOs can coexist with nitrifying bacteria in a single reactor. In addition, the usability of DNPAOs in the reactor can be improved by adding the anoxic phase after the oxic phase. These characteristics enable the AOAGS process to attain effective removal of both nitrogen and phosphorus. When acetate-based synthetic wastewater (COD: 600 mg/L, NH4-N: 60 mg/L, PO4-P: 10mg/L) was supplied to a laboratory-scale sequencing batch reactor under the operation of anaerobic/oxic/anoxic cycles, granular sludge with a diameter of 500 Pin was successfully formed within 1 month. Although the removal of both nitrogen and phosphorus was almost complete at the end of the oxic phase, a short anoxic period subsequent to the oxic phase was necessary for further removal of nitrogen and phosphorus. As a result, effluent concentrations of NH4-N, NOx-N and PO4-P were always lower than 1 mg/L. It was found that penetration depth of oxygen inside the granular sludge was approximately 100 mu m by microsensor measurements. in addition, from the microbiological analysis by fluorescence in situ hybridization, existence depth of polyphosphate-accumulating organisms was further than the maximum oxygen penetration depth. The water quality data, oxygen profiles and microbial community structure demonstrated that DNPAOs inside the granular sludge may be responsible for denitrification in the oxic phase, which enables effective nutrient removal in the AOAGS process. (c) 2006 Elsevier Ltd. All rights reserved.

    DOI

  • Sequencing Batch Membrane Biofilm Reactor for Simultaneous Nitrogen and Phosphorus Removal: Novel Application of Membrane-Aerated Biofilm

    A. Terada, T. Yamamoto, S. Tsuneda, A. Hirata

    Biotechnol. Bioeng.   94 ( 4 ) 730 - 739  2006年06月

  • マイクロバブル化オゾン酸化法および吸着脱リン法を組み込んだ新しい資源循環型排水処理システム

    鈴木康之, 近藤貴志, 常田聡, 稲森悠平

    用水と廃水   48 ( 5 ) 424 - 431  2006年05月

  • Esterification of lauric acid using lipase immobilized in the micropores of a hollow-fiber membrane

    Muneharu Goto, Hidetaka Kawakita, Kazuya Uezu, Satoshi Tsuneda, Kyoichi Saito, Masahiro Goto, Masao Tamada, Takanobu Sugo

    JAOCS, Journal of the American Oil Chemists' Society   83 ( 3 ) 209 - 213  2006年03月  [査読有り]

     概要を見る

    A porous anion-exchange hollow-fiber membrane was prepared by radiation-induced graft polymerization and chemical modification to immobilize lipase for enzymatic reaction in an organic solvent. The amount of anion-exchange group introduced to the porous hollow-fiber membrane was 2.5 mol/kgfiber. A lipase solution was allowed to permeate through the porous anion-exchange hollow-fiber membrane, and lipase molecules that adsorbed onto the grafted polymer brush were cross-linked with glutaraldehyde. The lipase was immobilized at a density of 0.14 kglipase/kgfiber, which was equivalent to a degree of multilayer binding of 20. Esterification was carried out by passing a solution of lauric acid and benzyl alcohol in anhydrous isooctane through the lipase-immobilized membrane, and lipase activity was determined. A reaction percentage of 50% was achieved at space velocity 68 h-1. The maximum immobilized lipase and native lipase activities were 8.9 and 0.38 mol/(h·kglipase), respectively. Thus, the activity of the immobilized lipase was 23.4 times higher than that of the native lipase. Copyright © 2006 by AOCS Press.

    DOI

  • Recovery of Sb(V) using a functional-ligand-containing porous hollow-fiber membrane prepared by radiation-induced graft polymerization

    H Kawakita, K Uezu, S Tsuneda, K Saito, M Tamada, T Sugo

    HYDROMETALLURGY   81 ( 3-4 ) 190 - 196  2006年03月  [査読有り]

     概要を見る

    A ligand-containing porous membrane was prepared by radiation-induced graft polymerization of an epoxy-group-containing monomer of glycidyl methacrylate onto a polyethylene porous hollow-fiber membrane and by subsequent conversion of the epoxy group to an N-methylglucamino (NMG) group at a density of 0.78 mmol/g of the membrane. Sb(V) solution was permeated through the NMG-ligand-containing porous hollow-fiber membrane. Optimum pH for Sb(V) recovery was 3.0. Breakthrough curves of Sb (V) overlapped irrespective of residence times of Sb (V) in the membrane, due to negligible diffusional mass-transfer resistance. Maximum amount of Sb (V) adsorbed was 130 mg/g-membrane, which was equivalent to 1.3 binding molar ratio. Repeated usage of the membrane for adsorption and elution was possible. (c) 2006 Elsevier B.V. All rights reserved.

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  • Long-term monitoring of the succession of a microbial community in activated sludge from a circulation flush toilet as a closed system

    T Hoshino, T Terahara, K Yamada, H Okuda, Suzuki, I, S Tsuneda, A Hirata, Y Inamori

    FEMS MICROBIOLOGY ECOLOGY   55 ( 3 ) 459 - 470  2006年03月  [査読有り]

     概要を見る

    The microbial diversity and community succession of a circulation flush toilet were investigated by terminal restriction fragment length polymorphism and cloning analyses. Clonal libraries of 16S rRNA gene on day 3 and day 127 were constructed. On day 3, 102 clones were sequenced; Proteobacteria and Bacteroidetes accounted for 27% and 45%, respectively. On day 127, Proteobacteria had increased to 43% and Bacteroidetes had decreased to 26% of a total of 100 clones. Terminal restriction fragment length polymorphism peaks were identified by in silico analysis of clone libraries. The relative abundances of Nitrosomonas increased from 1% to 6% with commencement of nitrification and denitrification. Similarly, the relative abundance of terminal restriction fragments generated from Xanthomonas increased from 3% to 10%. Therefore, these bacteria could play a prominent role in this process. To reveal the relationship between stability of the microbial community and performance of the system, microbial community succession was visualized by multidimensional scaling analysis. The microbial community structure changed markedly, particularly during the start-up period of the system. The plots then became stable after the start of nitrification and denitrification. This result suggests that the succession of microbial community structure had a correlation with the performance of the system.

    DOI

  • Growth characteristic of anaerobic ammonium-oxidizing bacteria in an anaerobic biological filtrated reactor

    K Isaka, Y Date, T Sumino, S Yoshie, S Tsuneda

    APPLIED MICROBIOLOGY AND BIOTECHNOLOGY   70 ( 1 ) 47 - 52  2006年03月  [査読有り]

     概要を見る

    The doubling time of anaerobic ammonium-oxidizing (anammox) bacteria in an anaerobic biological filtrated (ABF) reactor was determined. Fluorescence in situ hybridization analysis was used to detect and count anammox bacteria cells in anammox sludge. As a result, the populations of anammox bacteria at 14th and 21st days were 1.1x10(6) and 1.7x10(7) cells/ml reactor, respectively. From these results, the doubling time of anammox bacteria was calculated as 1.8 days, and the specific growth rate (mu) was 0.39 day(-1). This result indicated that the anammox bacteria have higher growth rate than the reported value (doubling time, 11 days). Furthermore, it was clearly demonstrated that nitrogen conversion rate was proportional to the population of anammox bacteria. Maintaining the ideal environment for the growth of anammox bacteria in the ABF reactor might lead to faster growth. This is the first report of the growth rate of anammox bacteria based on the direct counting of anammox bacteria.

    DOI

  • Characteristics of bacteria showing high denitrification activity in saline wastewater

    S Yoshie, T Ogawa, H Makino, H Hirosawa, S Tsuneda, A Hirata

    LETTERS IN APPLIED MICROBIOLOGY   42 ( 3 ) 277 - 283  2006年03月  [査読有り]

     概要を見る

    Aims: Denitrification efficiency at 10% salinity was compared with that at 2% salinity. The characteristics of bacterial strains isolated from the denitrification system, where an improvement of denitrification efficiency was observed at a high salinity were investigated.
    Methods and Results: Two continuous feeding denitrification systems for saline solutions of 2% and 10% salinity, were operated. Denitrification efficiency at 10% salinity was higher than that at 2% salinity. The bacterial strains were isolated using the trypticase soy agar (TSA) medium at 30 degrees C. The phylogenetic analysis of 16S rRNA gene sequences of isolates indicated that halophilic species were predominant at 10% salinity.
    Conclusions: The improvement of denitrification efficiency at a high salinity was demonstrated. The strains isolated from the denitrifying system with 10% salinity were halophilic bacteria, Halomonas sp. and Marinobacter sp., suggesting that these bacteria show a high denitrifying activity at 10% salinity.
    Significance and Impact of Study: The long-term acclimated sludge used in this study resulted in high denitrification performance at a high salinity, indicating that the design of a high-performance denitrification system for saline wastewater will be possible.

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  • Affinity capillary electrophoresis with a DNA-nanoparticle conjugate as a new tool for genotyping

    K Adachi, N Noda, M Nakashige, S Tsuneda, T Kanagawa

    JOURNAL OF CHROMATOGRAPHY A   1109 ( 2 ) 127 - 131  2006年03月  [査読有り]

     概要を見る

    We have developed a novel method for genotyping based on free solution affinity capillary electrophoresis. We prepared DNA-nail opal-tic le conjugates by mixing biotin-modified DNA and NeutrAvidin-modified polystyrene nanoparticles; this mixture was then injected into a capillary. Subsequently, we injected the fluorescent-labeled sample DNAs into the capillary, applied the voltage, increased its temperature after 7 min, and detected the fluorescence at its anodic end. This novel method was applied for genotyping human c-K-ras, and the three genotypes were definitely distinguishable with high reproducibility. This method can be easily automated, and it is useful for high-throughput gene mutation analysis. (c) 2006 Elsevier B.V. All fights reserved.

    DOI

  • Feasibility of a membrane-aerated biofilm reactor to achieve controllable nitrification

    A Terada, T Yamamoto, R Igarashi, S Tsuneda, A Hirata

    BIOCHEMICAL ENGINEERING JOURNAL   28 ( 2 ) 123 - 130  2006年02月  [査読有り]

     概要を見る

    A feasibility of a membrane-aerated biofilm reactor (MABR) for controllable nitrification was examined. The estimation of oxygen supply rate (OSR) with three polyacrylonitrile membrane modules revealed that specific OSR was equivalent in these membrane modules and OSR affected only air pressure, thus enabling control of aeration simply by adjustment of air pressure. A continuous nitrification experiment consisting of three reactors differing in membrane surface area investigated the reactor performance of the MABR at an air pressure of 23 kPa. The results indicated that the ammonia removal rate at steady state was dependent on membrane surface area, at rates nearly equivalent to that predicted by the above OSR experiment. The amount of bacteria adhering to the membrane surface was not completely proportional to membrane surface area due to clogging in a reactor with high membrane surface area, which accompanies a decrease in specific ammonia removal rate per biomass with membrane surface area. Stable ammonia removal rates at air pressures of 23, 45 and 100 kPa corresponded to the predicted values from the OSR experiment. Further, more than 80% oxygen utilization efficiency (OUE) was achieved under all operational conditions. indicating effective oxygen uptake by nitrifying bacteria under oxygen-depleted conditions. Based on these experiments, the MABR was shown to be a controllable nitrification system, and to be able to provide a reaction space for nitrification in a membrane-attached biofilm without altering the bulk conditions. (c) 2005 Elsevier B.V. All rights reserved.

    DOI

  • Improvement of denitrifying reaction rate by enhanced substrate transport within a cell-immobilized space by electrophoresis

    Satoshi Tsuneda, Shuichi Kaku, Hiroshi Hayashi, Satoshi Ohgushi, Akihiko Terada, Akira Hirata

    Kagaku Kogaku Ronbunshu   32 ( 6 ) 507 - 513  2006年  [査読有り]

     概要を見る

    In order to improve the microbial reaction rate within a cell-immobilized space, this study experimentally investigated enhanced substrate transport by electrophoresis of a specific ion. Batch-mode and continuous feeding denitrification tests were carried out in an autotrophic denitrifying bioreactor using sulfur-oxidizing microbes as a model system. Seed sludge and powdered sulfur were immobilized on fibrous carrier medium, and an electric field was applied through the cell-immobilized zone via inert electrodes on both sides of vessel. In batch-mode denitrification tests, nitrogen removal rate reached 1.99 g-N·m-3·h-1 when the electric field of 18V was reversed at intervals of 30min, as compared with 0.40g-N·m -3·h-1 when the electric field was not applied. These findings demonstrated that the denitrification rate was increased by promoting the transport of NO3- ions across the cell-immobilized zone by electrophoresis. In addition, no reduction of NO 3- to NO2- occurred, indicating that decrease of nitrogen compound was due to biological reaction. Mathematical simulation analysis using a model involving Monod-type reaction kinetics and the Stokes formula for NO3- mobility was in general agreement with the experimental results. The results of the continuous feeding test also indicated that electrophoresis improved the nitrogen removal rate. Copyright © 2006 The Society of Chemical Engineers, Japan.

    DOI

  • 生物学的窒素・リン除去プロセスにおける微生物生態と機能

    近藤貴志, 大坂利文, 青井議輝, 常田聡

    用水と廃水   48 ( 1 ) 53 - 60  2006年01月

  • ナノパーティクルを用いたアフィニティーキャピラリー電気泳動法による特定遺伝子の新規な検出手法の開発

    足立賢, 野田尚宏, 中繁誠人, 常田聡, 金川貴博

    化学工学シンポジウムシリーズ   79   106 - 110  2006年01月

  • Simultaneous nitrogen and phosphorus removal using denitrifying phosphate-accumulating organisms in a sequencing batch reactor

    S Tsuneda, T Ohno, K Soejima, A Hirata

    BIOCHEMICAL ENGINEERING JOURNAL   27 ( 3 ) 191 - 196  2006年01月  [査読有り]

     概要を見る

    In this study, an anaerobic/aerobic/anoxic process (referred to as an AOA process) using a sequencing batch reactor (SBR) was proposed for simultaneous phosphorus and nitrogen removal from wastewater. The AOA process was stably operated over more than one year when a certain amount of carbon substrate (40 mg-C/L in a reactor) was supplemented to inhibit aerobic phosphate uptake. The average nitrogen and phosphorus removal efficiencies were 83% and 92%, respectively. It was demonstrated that phosphate-accumulating organisms (PAOs) capable of utilizing nitrite as an electron acceptor, the so-called denitrifying phosphate-accumulating organisms (DNPAOs), could exist in the AOA process. Moreover, the ratio of anoxic phosphate uptake rate (PUR) to aerobic PUR (anoxic/aerobic PUR ratio), which indicates the fraction of DNPAOs in total PAOs, was experimentally evaluated. The results indicate that the AOA process has a much larger anoxic/aerobic PUR ratio than the conventional A(2)O (anaerobic/anoxic/aerobic) and AO (anaerobic/aerobic) processes. In conclusion, the AOA process allows DNPAOs to take an active part in simultaneous nitrogen and phosphorus removal in an SBR when a suitable amount of carbon substrate is supplied at the start of aerobic conditions. (c) 2005 Elsevier B.V. All rights reserved.

    DOI

  • High-rate nitrification using aerobic granular sludge

    S Tsuneda, M Ogiwara, Y Ejiri, A Hirata

    WATER SCIENCE AND TECHNOLOGY   53 ( 3 ) 147 - 154  2006年  [査読有り]

     概要を見る

    The performance of nitrifying granules, which had been produced in an aerobic upflow fluidised bed (AUFB) reactor, was investigated in various types of ammonia-containing wastewaters. When pure oxygen was supplied to the AUFB reactor with a synthetic wastewater containing a high concentration of ammonia (500g-N/m(3)), the ammonia removal rate reached 16.7 kg-N/m(3)/day with a sustained ammonia removal efficiency of more than 80%. The nitrifying granules possessing a high settling ability could be retained with a high density (approximately 10,000 g-MLSS/m(3)) in a continuous stirring tank reactor (CSTR) even under a short hydraulic retention time (44 min), which enabled a high-rate and stable nitrification for an inorganic wastewater containing low concentrations of ammonia (50 g-N/m(3)). Moreover, the nitrifying granules exhibited sufficient performance in the nitrification of real industrial wastewater containing high V concentrations of ammonia (1,000-1,400 g-N/m(3)) and salinity (1.2-2.2%), which was discharged from metal-refinery processes. When the nitrifying granules were used in cooperation with activated sludge to treat domestic wastewater containing organic pollutants as well as ammonia, they fully contributed to CA nitrification even though a part of activated sludge adhered onto the granule surfaces to form biofilms. These results show the wide applicability of nitrifying granules to various cases in the nitrification step of wastewater treatment plants.

    DOI

  • Evaluation of sludge reduction and phosphorus recovery efficiencies in a new advanced wastewater treatment system using denitrifying polyphosphate accumulating organisms

    Y Suzuki, T Kondo, Nakagawa, V, S Tsuneda, A Hirata, Y Shimizu, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   53 ( 6 ) 107 - 113  2006年  [査読有り]

     概要を見る

    A new biological nutrient removal process, anaerobic - oxic - anoxic (A/O/A) system using denitrifying polyphosphate-accumulating organisms (DNPAOs), was proposed. To attain excess sludge reduction and phosphorus recovery, the A/O/A system equipped with ozonation tank and phosphorus adsorption column was operated for 92 days, and water quality of the effluent, sludge reduction efficiency, and phosphorus recovery efficiency were evaluated. As a result, TOC, T-N and T-P removal efficiency were 85%, 70% and 85%, respectively, throughout the operating period. These slightly lower removal efficiencies than conventional anaerobic- anoxic-oxic (A/A/O) processes were due to the unexpected microbial population in this system where DNPAOs were not the dominant group but normal polyphosphate-accumulating organisms (PAOs) that could not utilize nitrate and nitrite as electron acceptor became dominant. However, it was successfully demonstrated that 34-127% of sludge reduction and around 80% of phosphorus recovery were attained. In conclusion, the A/O/A system equipped with ozonation an phosphorus adsorption systems is useful as a new advanced wastewater treatment plant (WWTP) to resolve the problems of increasing excess sludge and depleted phosphorus.

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  • Comprehensive Analysis of Cell Wall-Permeabilizing Conditions for Highly Sensitive Fluorescence in Situ Hybridization

    Kazuhiro Furukawa, Tatsuhiko Hoshino, Satoshi Tsuneda, Yuhei Inamori

    Microbes and Environments   21 ( 4 ) 227 - 234  2006年

     概要を見る

    The simultaneous detection of different bacterial strains carrying a certain functional gene is absolutely imperative in order to detect bacteria on the basis of functional gene expression products (mRNA) in situ. Functional genes are possessed by bacterial strains with different types of cell walls
    therefore, the optimization of conditions for digesting different types of cell walls is significant. In this study, we defined the optimal conditions for permeabilization in eight bacterial strains belonging to different phylogenetic divisions using solutions containing different concentrations of lysozyme and/or achromopeptidase, for conventional fluorescence in situ hybridization (FISH), digoxigenin (DIG)-FISH, and catalyzed reporter deposition (CARD)-FISH with a rRNA-targeting oligonucleotide probe. Most bacterial strains were successfully detected using CARD-FISH with lysozyme 10 mg/ml pretreatment. Additionally, achromopeptidase pretreatment combined with lysozyme pretreatment was a highly effective means of permeabilizing bacterial strains that were unable to be detected using lysozyme pretreatment. However, this additional pretreatment resulted in a loss of cell morphology in some bacterial strains due to excessive permeabilization. Consequently, permeabilizing conditions for applying highly sensitive FISH to the well-defined target bacterial strains used in this study were optimized. The results of this study will contribute to the optimization of permeabilizing conditions, which is one of the most important factors for the successful application of highly sensitive FISH. © 2006, Japanese Society of Microbial Ecology &amp
    The Japanese Society of Soil Microbiology. All rights reserved.

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  • 繊維化スラグの複合的利用による低濃度重金属汚染水処理

    常田聡, 酒井寿郎, 林浩志

    水環境学会誌   28 ( 11 ) 651 - 655  2005年11月

  • 窒素除去プロセスにおける複合微生物系解析とその利用

    青井議輝, 大坂利文, 常田聡

    水環境学会誌   28 ( 8 ) 474 - 478  2005年08月

  • Single-stage autotrophic nitrogen-removal process using a composite matrix immobilizing nitrifying and sulfur-denitrifying bacteria

    Y Aoi, Y Shiramasa, E Kakimoto, S Tsuneda, A Hirata, T Nagamune

    APPLIED MICROBIOLOGY AND BIOTECHNOLOGY   68 ( 1 ) 124 - 130  2005年07月  [査読有り]

     概要を見る

    We developed a novel single-stage autotrophic nitrogen-removal process comprised of two composite immobilized biomass layers-one of nitrifying bacteria and one of sulfar-denitrifying bacteria and elemental sulfur-in a Fe-Ni fibrous slag matrix. Nitrification and consumption of dissolved oxygen occurred in the outer part and sulfur denitrification in the anoxic inner part of the composite matrix, thus realizing autotrophic nitrogen removal in a single reactor. The complete conversion of ammonia into N-2 in a single reactor was demonstrated in both batch-mode incubation and continuous-feed operation. The spatial profiles of the ammonia-oxidizing bacteria and denitrifying bacteria were evaluated by real-time PCR, targeting their functional genes, and stratification of these two types was observed in the matrix after several months of incubation. This process does not require any specific reactor type or conditions and thus has the potential to be applied to many different wastewater treatment processes due to its simplicity in both operation and construction.

    DOI

  • Elucidation of dominant effect on initial bacterial adhesion onto polymer surfaces prepared by radiation-induced graft polymerization

    A Terada, A Yuasa, S Tsuneda, A Hirata, A Katakai, M Tamada

    COLLOIDS AND SURFACES B-BIOINTERFACES   43 ( 2 ) 99 - 107  2005年06月  [査読有り]

     概要を見る

    Surface-modified polyethylene (PE) membrane sheets were prepared by the radiation-induced graft polymerization (RIGP) of an epoxy-group-containing monomer, glycidyl methacrylate (GMA). The epoxy ring of GMA was opened by introducing diethylamine (DEA) or sodium sulfite (SS). We examined the properties of these sheets by measuring the amount of grafting polymer, surface roughness and membrane potential, and also investigated the adhesion of five Gram-negative bacteria, Escherichia coli, Pseudomonas aeruginosa, Pseudomonas putida, Pseudomonas fluorescens and Paracoccus denitrificans, onto the prepared sheet surfaces. A linear relationship between the degree of grafting (dg) and surface roughness was observed. Moreover, membrane potential was dependent on the amount of DEA or SS as the ionizable group. These results indicate that RIGP enables the control of the physicochemical properties of such a sheet surface by adjusting dg and the subsequent conversion of functional groups. A batch test on bacterial adhesion onto the sheets clarified that the DEA-containing sheet (DEA sheet) exhibited an adhesion rate constant, k, significantly greater than those of other types of sheet. Clearly, the adhesion rate constant of the DEA sheet increased with dg, indicating that electrostatic interaction is the most decisive factor for bacterial adhesion when it works as an attractive force. Furthermore, the densities of bacteria adhering onto the GMA-containing sheet (GMA sheet) and the SS-containing sheet (SS sheet) were almost the same as that onto a PE sheet, whereas that onto a DEA sheet significantly increased. Thus, the introduction of the GMA- and SS-containing graft chain did not have much influence on bacterial adhesion onto the surfaces, supporting the conclusion that the promotion of bacterial adhesion onto the GMA and SS sheets was due to an increase in surface area resulting from RIGP. Moreover, the scanning electron microscopy images of the sheet surfaces indicate that the conditions and morphologies of initial bacterial adhesion are dependent on surface properties, particularly membrane potential. (c) 2005 Elsevier B.V. All rights reserved.

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  • ビール粕成形炭による観賞魚用水槽の水質浄化

    岡本裕行, 芝田隼次, 村山憲弘, 山本秀樹, 塚元祐二, 飯塚梨加, 常田聡

    環境資源工学   52 ( 1 ) 25 - 31  2005年05月

  • Quantification of genetically modified soybean by quenching probe polymerase chain reaction

    H Tani, N Noda, K Yamada, S Kurata, S Tsuneda, A Hirata, T Kanagawa

    JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY   53 ( 7 ) 2535 - 2540  2005年04月  [査読有り]

     概要を見る

    Quenching probe (QProbe) polymerase chain reaction (PCR) is a simple and cost-effective real-time PCR assay in comparison with other real-time PCR assays such as the TaqMan assay. We used QProbe-PCR to quantify genetically modified (GM) soybean (Roundup Ready soybean). We designed event-specific QProbes for Le1 (soy endogenous gene) and RRS (recombinant gene), and we quantified certified reference materials containing 0.1, 0.5, 1, 2, and 5% GM soybean. The TaqMan assay was also applied to the same samples, and the results were compared. The accuracy of QProbe-PCR was similar to that of TaqMan assay. When GM soybean content was 0.5% or more, the relative standard deviations of QProbe-PCR were less than 20%. QProbe-PCR is sensitive enough to monitor labeling systems and has acceptable levels of accuracy and precision.

    DOI

  • Characterization of denitrifying polyphosphate-accumulating organisms in activated sludge based on nitrite reductase gene

    S Tsuneda, R Miyauchi, T Ohno, A Hirata

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   99 ( 4 ) 403 - 407  2005年04月  [査読有り]

     概要を見る

    Nitrite reductase gene (nirS) fragments in the activated sludge obtained from a sequencing batch reactor (SBR) under anaerobic-aerobic condition were cloned and classified by restriction fragment length polymorphism (RFLP) analysis, and representative fragments were sequenced. One of the nirS clones was approximately 70% of all nirS clones in anaerobic/aerobic (existing oxygen and nitrate) cycle operation in which a large amount of anoxic phosphate uptake was observed. Although the activated sludge samples analyzed might contain bacteria that did not accumulate polyphosphate, it was likely that this nirS fragment sequence was that from denitrifying polyphosphate-accumulating organisms (DNPAOs) which can utilize both oxygen and nitrate as electron acceptors. The sequence was similar to the WrS sequences of Thauera mechemichensis (83% similarity) and Azoarcus tolulyticus (83% similarity) both of which belong to the Rhodocyclus group.

    DOI

  • Characteristics and Applicability of Nitrifying Granules Produced in an Aerobic Upflow Fluidized Bed Reactor

    S. Tsuneda, Y. Ejiri, M. Ogiwara, T. Nagano, A. Hirata

    Aerobic Granular Sludge, Water Environmental Management Series (WEMS)     15 - 24  2005年04月

  • 脱窒性リン蓄積細菌を利用した下水処理技術およびリン資源回収の可能性

    常田聡, 大野高史, 副島孝一, 平田彰

    環境バイオテクノロジー学会誌   4 ( 2 ) 95 - 99  2005年03月

  • ステップ流入式嫌気/好気/無酸素プロセスによる窒素・リン同時除去

    常田聡, 大野高史, 副島孝一, 平田彰

    用水と廃水   47 ( 3 ) 230 - 236  2005年03月

  • Effect of salinity on nitrous oxide emission in the biological nitrogen removal process for industrial wastewater

    S Tsuneda, M Mikami, Y Kimochi, A Hirata

    JOURNAL OF HAZARDOUS MATERIALS   119 ( 1-3 ) 93 - 98  2005年03月  [査読有り]

     概要を見る

    The effects of wastewater salinity on both nitrogen removal efficiency and N2O emission rate were investigated in a single nitrification process, a single denitrification process and an anoxic-oxic activated sludge process. In the single nitrification process, by increasing the salt concentration from 1.0 to 2.0 wt%, the N2O conversion ratio in the steady state increased by 2.2 times, from 0.22 to 0.48%. In the single denitrification process, a minimal change in the N2O conversion ratio was observed in the steady state even when the salt concentration was increased from 3.0 to 5.0 wt%. From the results of the anoxic-oxic activated sludge process, it was found that a salt concentration increase from 1.6 to 3.0 wt% significantly increases the N2O conversion ratio from 0.7 to 13%. It is suggested that an increase in salt concentration markedly influences N2O emission both directly and indirectly via the inhibition of N2O reductase activity. The indirect inhibition is due to the high concentration of dissolved oxygen which is transported from the oxic tank to the anoxic tank through the circulated liquid. Thus, the salt concentration should be maintained below 3.0% to suppress N2O emission in an anoxic-oxic activated sludge process. (c) 2004 Elsevier B.V. All rights reserved.

    DOI

  • リアルタイム制御法を用いた新規窒素除去プロセスの開発

    岸田直裕, 金主鉉, 須藤隆一, 佐々木弘, 常田聡

    ケミカルエンジニヤリング   50 ( 3 ) 108 - 113  2005年02月

  • Water Purification Properties of Charcoal Bricks Made from Beer Lees

    Hiroyuki Okamoto, Junji Shibata, Norihiro Murayama, Hideki Yamamoto, Yuji Tsukamoto, Rika Iizuka, Satoshi Tsuneda

    Resources Processing   52 ( 1 ) 25 - 31  2005年  [査読有り]

     概要を見る

    The performance of charcoal bricks made from beer lees (MaltCeramics, MC) was investigated as the material for purification of water breeding goldfish in order to compare with gravel and activated charcoal. The goldfish used in this study discharges 0.409 mg/D-g of TOC, 0.26 mg/D-g of NH4-N, 0.024 mg/D-g of NO3-N and 0.007 mg/D-g of T-P. It was confirmed that MC is useful for the carrier of microorganisms and it is possible to reduce soluble organic matter and soluble nitrogen compound such as NH4-N, NO3-N and NO2-N as same as activated charcoal. In the case of MC, NH4-N is decomposed to form NO2-N and NO3-N within 50 h. NO2-N and NO3-N are the decomposition products of NH4-N substrate and NO2-N is denitrated for 50–80 h. NH4-N and NO2-N are rapidly decomposed, but the denitrification of NO3-N is a very slow reaction. TOC is decreased down to the initial concentration level for 20–30 h. MC contains phosphorus at the ratio of about 2 wt%, which is soluble in water, and some minerals. It is considered that they would activate bacteria in water. © 2005, The Resources Processing Society of Japan. All rights reserved.

    DOI

  • Comparison of spatial organization in top-down- and membrane-aerated biofilms: a numerical study

    A Bell, Y Aoi, A Terada, S Tsuneda, A Hirata

    WATER SCIENCE AND TECHNOLOGY   52 ( 7 ) 173 - 180  2005年  [査読有り]

     概要を見る

    The study of community structure in wastewater biofilms is made difficult by the slow growth rates and high environmental sensitivities of autotrophic nitrifiers. Simulations of such films can generate data quickly and without susceptibility to random environmental perturbation. This study uses a 2D cellular automaton model to compare the community structures of biofilms grown under top-down and membrane aeration conditions. This study found dramatic differences in community structure between the two approaches, most notably the emergence of a niche at the solid - biofilm interface that facilitates the growth of nitrite oxidizing bacteria.

  • Molecular analysis of microbial population transition associated with the start of denitrification in a wastewater treatment process

    T Hoshino, T Terahara, S Tsuneda, A Hirata, Y Inamori

    JOURNAL OF APPLIED MICROBIOLOGY   99 ( 5 ) 1165 - 1175  2005年  [査読有り]

     概要を見る

    Aims; The objective of this study is to determine the bacteria playing an important role in denitrification by monitoring the molecular dynamics accompanying the start of denitrification.
    Methods and Results: cDNA reverse-transcribed from 16S rRNA was amplified with fluorescent labelled primer for terminal restriction fragment length polymorphism (T-RFLP) analysis and an unlabelled primer for cloning analysis. The terminal restriction fragments (T-RFs) that increased in association with the start of denitrification were determined. These T-RFs were identified by in silico analysis of 16S rRNA sequences obtained from cloning. As a result, it was clearly observed that the bacteria belonging to the genera Hydrogenophaga and Acidovorax increased in number after the start of denitrification.
    Conclusions: It was demonstrated that T-RFLP analysis targeting 16S rRNA is appropriate for the daily monitoring of a bacterial community to control wastewater treatment processes. Combination of the results of T-RFLP analysis and 16S rRNA clone library indicated that the bacteria belonging to the genera Hydrogenophaga and Acidovorax play an important role in denitrification.
    Significance and Impact of the Study: The results of this study provide new insight to the 16S rRNA level of active denitrifying bacteria in wastewater treatment processes.

    DOI

  • 硝化グラニュールを利用した高塩濃度産業廃水処理

    星野辰彦, 広沢英信, 松川忠史, 小川知幸, 江尻慶央, 常田聡, 平田彰

    日本水処理生物学会誌   40 ( 4 ) 137 - 142  2004年12月

  • Monitoring the microbial population dynamics at the start-up stage of wastewater treatment reactor by terminal restriction fragment length polymorphism analysis based on 16S rDNA and rRNA gene sequences

    T Terahara, T Hoshino, S Tsuneda, A Hirata, Y Inamori

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   98 ( 6 ) 425 - 428  2004年12月  [査読有り]

     概要を見る

    The microbial population dynamics at the start-up stage of a wastewater treatment reactor was investigated using terminal restriction fragment length polymorphism (T-RFLP) analysis based on 16S rDNA and rRNA gene sequences. The results of fragment peaks suggested that the number and activity of nitrifying bacteria increased in association with the start of nitrification, and the relative ratios of 16S rRNA of these bacteria changed prior to those of the 16S rDNA. Furthermore, multidimensional scaling (MDS) analysis revealed that the 16S rRNA exhibited wider dispersion than the 16S rDNA at the start-up stage, indicating that the diversity of 16S rRNA in the microbial communities was strongly affected by environmental changes.

  • Significance of cell electrokinetic properties determined by soft-particle analysis in bacterial adhesion onto a solid surface

    S Tsuneda, H Aikawa, H Hayashi, A Hirata

    JOURNAL OF COLLOID AND INTERFACE SCIENCE   279 ( 2 ) 410 - 417  2004年11月  [査読有り]

     概要を見る

    The influence of extracellular polymeric substances (EPSs) on bacterial cell electrokinetic properties and on cell adhesion onto glass beads in connection with bacterial cell electrokinetic properties was investigated using 12 heterotrophic bacterial strains. Bacterial cell surface properties such as the softness 1/lambda and charge density ZN were determined by Ohshima's soft-particle analysis using the measured electrophoretic mobility as a function of ionic strength. In 10 of 12 strains, when EPSs covering the cell surface were removed, the softness of the cell decreased, indicating that EPS adsorption enhanced the ease of liquid fluid in the ion-penetrable layer on the cell surface. On the other hand, the negative charge density of the cell surface increased for 9 of 12 strains, suggesting that EPSs covering the cell surface decreased the negative charge density of the cell surface layer. In addition, the characteristics of bacterial cell adhesion onto glass beads were evaluated by the packed-bed method and the data were interpreted to indicate cell adhesiveness. As a result, the efficiency of cell adhesion onto glass beads increased as negative cell surface potential Psi(0) decreased, whereas there seemed to be no correlation between zeta potential and cell adhesiveness. Cell surface potential Psi(0), which was derived by taking the bacterial polymer layer with EPSs into consideration, provided a more detailed understanding of the electrokinetic properties of bacterial cells. (C) 2004 Elsevier Inc. All rights reserved.

    DOI

  • Removal of antimony(III) using polyol-ligand-containing porous hollow-fiber membranes

    T Saito, S Tsuneda, A Hirata, S Nishiyama, K Saito, K Saito, K Sugita, K Uezu, M Tamada, T Sugo

    SEPARATION SCIENCE AND TECHNOLOGY   39 ( 13 ) 3011 - 3022  2004年09月  [査読有り]

     概要を見る

    A polyol-ligand-containing porous hollow-fiber membrane capable of removing antimony (III) from a liquid stream was prepared by radiation-induced graft polymerization of an epoxy-group-containing vinyl monomer, glycidyl methacrylate (GMA), and subsequent functionalization with N-methylglucamine (NMG) and 3-amino-1,2-propanediol (APD). The resultant chelate-forming group density was 1.6 mol per kg of the NMG-group-containing porous hollow-fiber membrane. An antimony (111) oxide solution (10 mg per L, pH 3.6-13) was forced to permeate through the submicron-diameter pores of the chelating porous hollow-fiber membrane. The antimony concentration of the effluent penetrating the outside surface of the hollow fiber was determined as a function of the effluent volume. The breakthrough or dynamic adsorption capacity for antimony was 54 g of Sb per kg of membrane at pH 11. Because of negligible diffusional mass-transfer resistance, the breakthrough curves overlapped irrespective of the permeation rate of the antimony solution across the chelating porous hollow-fiber membranes.

    DOI

  • 高度リン回収および余剰汚泥減容化を志向した排水処理プロセスの開発および評価

    稲森悠平, 中川和哉, 鈴木康之, 近藤貴志, 常田聡, 平田彰

    用水と廃水   46 ( 8 ) 671 - 677  2004年08月

  • Expression of amoA mRNA in wastewater treatment processes examined by competitive RT-PCR

    Y Aoi, Y Shiramasa, Y Masaki, S Tsuneda, A Hirata, A Kitayama, T Nagamune

    JOURNAL OF BIOTECHNOLOGY   111 ( 2 ) 111 - 120  2004年07月  [査読有り]

     概要を見る

    The expression of ammonia monooxygenase encoding mRNA (amoA mRNA) in a wastewater treatment process was analyzed in an attempt to propose an effective target for the monitoring of nitrifying bacteria in engineered systems or natural environments. The quick response (1-2 h) of amoA mRNA transcription to the recovery of ammonia oxidation activity induced by the sudden exposure to ammonia was observed in a short-time batch-mode incubation whereas the amount of amoA DNA did not markedly change during the incubation under any conditions. In the continuous feeding-operation, amoA mRNA level dynamically changed in response to the change in the surrounding environmental conditions and increase in ammonia oxidation rate. Although, amoA mRNA level did not quickly respond to the decrease in ammonia oxidation activity, it decreases over long time scales. These results suggest that the profiles of amoA mRNA expression can be used as an indicator of the ammonia oxidation activity. (C) 2004 Elsevier B.V. All rights reserved.

    DOI

  • 脱窒性リン蓄積細菌を用いた水処理技術

    常田聡, 大野高史, 安祚煥, 平田彰

    水処理技術   45 ( 6 ) 261 - 266  2004年06月

  • Structure of polyol-ligand-containing polymer brush on the porous membrane for antimony(III) binding

    T Saito, H Kawakita, K Uezu, S Tsuneda, A Hirata, K Saito, M Tamada, T Sugo

    JOURNAL OF MEMBRANE SCIENCE   236 ( 1 ) 65 - 71  2004年06月  [査読有り]

     概要を見る

    A polyol-ligand-containing porous hollow-fiber membrane for the recovery of antimony(III) was prepared by radiation-induced graft polymerization of an epoxy-group-containing vinyl monomer, glycidyl methacrylate (GMA), and by subsequent functionalization with N-methylglucamine (NMG) and 3-amino-1,2-propanediol (APD), that forma coordination complex with Sb(III). The structure of NMG-Sb(III) and APD-Sb(III) complexes in aqueous solution were determined by electron ionization-time-of-flight mass spectrometer (ESI-TOF-MS), and the binding ratio of NMG or APD to Sb(III) is 2: 1. An antimony(III) oxide solution (10 mg Sb/l, pH 11.4) was forced to permeate through the submicron-diameter pores of the polyol-ligand-containing porous hollow-fiber membranes. The equilibrium binding capacity for antimony(III) to the NMG-ligand-containing porous hollow-fiber membrane, 96 gSb/kg, was 10 times higher than that of the APD membrane. In a further study of the NMG membrane, the equilibrium binding ratios for antimony(III) to NMG groups were all approximately 0.5, illustrating that the NMG-Sb(III) complex on the fibers was in the ratio of 2:1. The results of computational structural analysis of the NMG-Sb(III) complex were in agreement with the experimental results of binding ratio. It was verified that an antimony(III) ion formed a coordination complex with two adjacent hydroxyl groups of two NMG moieties. The length of a functional group and the distance between functional groups on the polymer brush were significant factors to bind antimony(III) through the computational simulation. (C) 2004 Elsevier B.V. All rights reserved.

    DOI

  • Simplified modeling of simultaneous reaction kinetics of carbon oxidation and nitrification in biofilm processes

    S Tsuneda, JA Auresenia, K Hibiya, A Hirata

    ENGINEERING IN LIFE SCIENCES   4 ( 3 ) 239 - 246  2004年06月  [査読有り]

     概要を見る

    Batch experiments with varying initial substrate concentrations and biomass volumes were performed in a three-phase fluidized bed biofilm reactor treating simulated domestic wastewater to study the simultaneous carbon oxidation and nitrification in the biofilm Process. A simplified mass balance equation for the biofilm was proposed and five different kinetic rate equations were used to match the actual data. The kinetic parameters were obtained by nonlinear regression analysis on a set of two differential equations representing the simultaneous carbon oxidation and nitrification. The competitive inhibition model incorporating the effects of total organic carbon (TOC) concentrations on nitrification rates was the best-suited model based on the average r(2). In this model, oxygen concentration and its affinity constants were not included. Instead, it was assumed that the rate of carbon oxidation is independent of the NH4+-N, while nitrification is affected by TOC. The number of parameters was successfully minimized without reducing its ability to accurately predict the bulk concentration time course, which would reduce computational complexity and possibly enhance the availability for an actual wastewater treatment process.

    DOI

  • Simple Prediction of Oxygen Penetration Depth in Biofilms for Wastewater Treatment

    K. Hibiya, J. Nagai, S. Tsuneda, A. Hirata

    Biochem. Eng. J.   19 ( 1 ) 61 - 68  2004年06月

  • Design of 16S rRNA-targeted oligonucleotide probes and microbial community analysis in the denitrification process of a saline industrial wastewater treatment system

    S Yoshie, N Noda, S Tsuneda, A Hirata, Y Inamori

    FEMS MICROBIOLOGY LETTERS   235 ( 1 ) 183 - 189  2004年06月  [査読有り]

     概要を見る

    Three 16S rRNA-targeted oligonucleotide probes, namely, PSMg437 targeting several members of the genus Pseudomonas, Hlm474 targeting several members of the genus Halomonas, and Clw844 targeting several members of the genus Colwellia, were designed. The microbial community structure and nitrogen removal ability of nitrate-containing saline wastewater treatment systems with anaerobic packed bed and fluidized bed were monitored. Direct cell counting using fluorescence in situ hybridization (FISH) images revealed that various phylogenetic groups were evenly distributed in the anaerobic packed bed whereas members of the genus Halomonas were dominant particularly in the anaerobic fluidized bed. These results suggest that the microbial communities produced by different flow conditions correlated with denitrification ability in saline industrial wastewater treatment systems. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.

    DOI

  • Comparative analysis of genetic diversity and expression of amoA in wastewater treatment processes

    Y Ebie, N Noda, H Miura, M Matsumura, S Tsuneda, A Hirata, Y Inamori

    APPLIED MICROBIOLOGY AND BIOTECHNOLOGY   64 ( 5 ) 740 - 744  2004年06月  [査読有り]

     概要を見る

    The genetic diversity and expression of amoA of autotrophic ammonia oxidizers in wastewater treatment processes were investigated by RT-PCR and denaturing gradient gel electrophoresis (DGGE) in order to identify active components of ammonia-oxidizer populations in a such processes. Ammonia oxidizers, evidenced by the presence of amoA mRNA, were regarded as metabolically active. The DGGE profiles derived from amoA mRNA and from its gene, which were amplified by RT-PCR or PCR using samples collected from a bench-scale reactor treating high concentration of inorganic ammonia, were similar. In contrast, RNA and DNA-derived DGGE profiles from three domestic wastewater treatment facilities were different from each other. These data indicate that the dominant ammonia oxidizers in the bench-scale reactor exhibited ammonia-oxidizing activity, whereas some ammonia oxidizers in the domestic wastewater treatment facilities apparently did not express high levels of amoA mRNA.

    DOI

  • T-RFLP法による排水処理細菌叢の迅速モニタリング

    星野辰彦, 寺原猛, 常田聡, 平田彰, 稲森悠平

    用水と廃水   46 ( 5 ) 408 - 412  2004年05月

  • Salinity decreases nitrite reductase gene diversity in denitrifying bacteria of wastewater treatment systems

    S Yoshie, N Noda, S Tsuneda, A Hirata, Y Inamori

    APPLIED AND ENVIRONMENTAL MICROBIOLOGY   70 ( 5 ) 3152 - 3157  2004年05月  [査読有り]

     概要を見る

    Investigation of the diversity of nirK and nirS in denitrifying bacteria revealed that salinity decreased the diversity in a nitrate-containing saline wastewater treatment system. The predominant nirS clone was related to nirS derived from marine bacteria, and the predominant. nirK clone was related to nirK of the genus Alcaligenes.

    DOI

  • メンブレンエアレーション法を応用した単一槽内有機物・窒素同時除去システム

    寺田昭彦, 日比谷和明, 常田聡, 平田彰

    用水と廃水   46 ( 2 ) 148 - 155  2004年02月

  • 界面特性を利用した細菌細胞の付着・脱着制御法

    林浩志, 二瓶智也, 生木大志, 常田聡, 平田彰, 佐々木弘

    資源と素材   120 ( 1 ) 54 - 59  2004年01月

  • Transition of bacterial spatial organization in a biofilm monitored by FISH and subsequent image analysis

    Y Aoi, S Tsuneda, A Hirata

    WATER SCIENCE AND TECHNOLOGY   49 ( 11-12 ) 365 - 370  2004年  [査読有り]

     概要を見る

    The dynamic transition of bacterial community structure in a biofilm was monitored by the fluorescence in situ hybridization (FISH) technique and subsequent image analysis. Heterotrbphic bacteria that had occupied the outer layer were gradually decreased whereas ammonia-oxidizing bacteria (AOB) gradually increased their growth activity and extended their existence area to the outer layer of the biofilm through the gradual reduction of the C/N ratio. The spatial organization of AOB in the biofilm dynamically changed responding to the environmental conditions such as pH fluctuation and lack of dissolved oxygen (DO) and had great influence on the nitrification activity. The accumulation of nitrite was observed at lower DO concentration, which might be due to the property that nitrite-oxidizing bacteria (NOB) possess of higher K-m values for oxygen than AOB.

  • Formation mechanism of nitrifying granules observed in an aerobic upflow fluidized bed (AUFB) reactor

    S Tsuneda, Y Ejiri, T Nagano, A Hirata

    WATER SCIENCE AND TECHNOLOGY   49 ( 11-12 ) 27 - 34  2004年  [査読有り]

     概要を見る

    The influences of trace metals in the wastewater and shear stress by aeration were particularly examined to clarify the formation mechanism of nitrifying granules in an aerobic upflow fluidized bed (AUFB) reactor. It was found that Fe added as a trace element to the inorganic wastewater accumulated at the central part of the nitrifying granules. Another result obtained was that suitable shear stress by moderate aeration (0.07-0.20 L/min/L-bed) promoted granulation. Furthermore, it was successfully demonstrated that pre-aggregation of seed sludge using hematite promoted core formation, leading to rapid production of nitrifying granules. From these results, a nitrifying granulation mechanism is proposed: 1) as a first step, nitrifying bacteria aggregate along with Fe precipitation, and then the cores of granules are formed; 2) as a second step, the aggregates grow to be spherical or elliptical in form due to multiplication of the nitrifying bacteria and moderate shear stress in the reactor, and then mature nitrifying granules are produced. Fluorescence in situ hybridization (FISH) analysis successfully visualized the change in the spatial distribution of nitrifying bacteria in the granules, which supports the proposed granulation mechanism.

  • Enhancement of biofilm formation onto surface-modified hollow-fiber membranes and its application to a membrane-aerated biofilm reactor

    A Terada, T Yamamoto, K Hibiya, S Tsuneda, A Hirata

    WATER SCIENCE AND TECHNOLOGY   49 ( 11-12 ) 263 - 268  2004年  [査読有り]

     概要を見る

    Surface-modified hollow-fiber membranes were prepared by radiation-induced grafting of an epoxy-group-containing monomer, glycidylmethacrylate (GMA), onto a polyethylene-based fiber (PE-fiber). The epoxy ring of GMA was opened by introduction of diethylamine (DEA). The bacterial adhesivity to this material (DEA-fiber) was tested by immersion into a nitrifying bacterial suspension. The initial adhesion rates and the amount of attached bacteria of the DEA-fiber were 6-10-fold and 3-fold greater than those of the PE fiber, respectively. A membrane-aerated biofilm reactor (MABR) composed of DEA fibers was developed for partial nitrification with nitrite accumulation. Prior to the nitrification test, it was confirmed that the oxygen supply rate (OSR) was proportional to air pressure up to 100 kPa, allowing easy control of oxygen supply. Stable nitrite accumulation was observed in the partial nitrification test at a fixed oxygen supply throughout the operation period, indicating that oxygen was consumed only by ammonia oxidizers. Furthermore, it was demonstrated that oxygen utilization efficiency (OUE) in the ammonia oxidation process was nearly 100% after 300 h incubation.

  • Quantitative analysis of amoA mRNA expression as a new biomarker of ammonia oxidation activities in a complex microbial community

    Y Aoi, Y Masaki, S Tsuneda, A Hirata

    LETTERS IN APPLIED MICROBIOLOGY   39 ( 6 ) 477 - 482  2004年  [査読有り]

     概要を見る

    Aims: To quantitatively analyse the changes to amoA mRNA (ammonia mono-oxygenase encoding mRNA) profiles in response to a change in ammonia oxidation activity in a complex microbial community.
    Methods and Results: The amoA mRNA levels in both a batch-mode incubation and a continuously fed nitrification reactor were determined by real-time reverse transcription-PCR analysis. The amoA mRNA level changed rapidly in response to the change in environmental conditions which affect ammonia oxidation activity.
    Conclusion: An increase in amoA mRNA level can be detected within 1-2 h in response to an initiation of cell activity whereas a decrease in amoA mRNA level is detected within 24 h in response to a cessation of activity.
    Significance and Impact of the Study: amoA mRNA, which shows sensitive response to ammonia oxidation activity, can be used as a biomarker of ammonia oxidation activity in wastewater treatment processes where many bacterial species exist.

    DOI

  • Automatic control strategy for biological nitrogen removal of low C/N wastewater in a sequencing batch reactor

    N Kishida, JH Kim, M Chen, S Tsuneda, H Sasaki, R Sudo

    WATER SCIENCE AND TECHNOLOGY   50 ( 10 ) 45 - 50  2004年  [査読有り]

     概要を見る

    To establish an automatic control system of external carbon addition in biological nitrogen removal, a bench-scale sequencing batch reactor with real-time control strategy was designed in this study. An oxidation-reduction potential (ORP) profile as used for automatic control of external carbon addition. The mean removal efficiency of total organic carbon was over 98%. Complete denitrification in an anoxic phase and complete denitrification and nitrification in anoxic and oxic phases were accomplished, respectively, because the oxic and anoxic periods were also appropriately controlled with ORP and pH profiles, respectively. Mean removal efficiency of total nitrogen was over 95%. When concentration of influent wastewater was changed, volume of additional carbon was automatically changed with the influent, fluctuation, and flexible hydraulic retention time was achieved in this system.

  • 硫酸塩還元細菌を利用したFe-EDTA分解除去プロセスの構築

    常田聡, 塩野貴史, 中村和之, 平田彰

    日本水処理生物学会誌   39 ( 4 ) 167 - 174  2003年12月

  • 放射性同位体トレーサー法を用いた水圏生態系マイクロコズムに及ぼすリンの影響評価

    近藤貴志, 板山朋聡, 常田聡, 平田彰, 稲森悠平

    日本水処理生物学会誌   39 ( 4 ) 175 - 181  2003年12月

  • ビール粕を原料とする成形炭の水質浄化特性

    岡本裕行, 八木紀依, 井上雅夫, 山崎秀一, 石田清治, 芝田隼次, 山本秀樹, 林浩志, 塩野貴史, 常田聡, 平田彰

    環境資源工学   50 ( 4 ) 165 - 174  2003年12月

  • RT-PCR法を用いた生活排水処理プロセスにおけるアンモニア酸化細菌の活性発現のモニタリング解析

    蛯江美孝, 三浦英智, 野田尚宏, 松村正利, 常田聡, 平田彰, 水落元之, 稲森悠平

    日本水処理生物学会誌   39 ( 4 ) 199 - 207  2003年12月

  • Characterization of nitrifying granules produced in an aerobic upflow fluidized bed reactor

    S Tsuneda, T Nagano, T Hoshino, Y Ejiri, N Noda, A Hirata

    WATER RESEARCH   37 ( 20 ) 4965 - 4973  2003年12月  [査読有り]

     概要を見る

    Since nitrification is the rate-determining step in the biological nitrogen removal from wastewater, many research studies have been conducted on the immobilization of nitrifying bacteria. In this research, granulation of nitrifying bacteria in an aerobic upflow fluidized bed (AUFB) reactor in a nitrification process for inorganic wastewater containing 500 g/m(3) of NH(4)(+)-N was investigated. It was observed that spherical, pseudocubic and elliptical granules with a diameter of 346 mum were produced at the bottom of the reactor after 300 days. Denaturing gradient gel electrophoresis analysis revealed that Nitrosomonas-like bacteria were the dominant ammonia-oxidizing species in the granules. Many colonies of Nitrosomonas-like bacteria were found in the outer part of the granules based on the spatial distribution analysis by fluorescence in situ hybridization. By stepwise reduction of the hydraulic retention time, the ammonia removal rate of the AUFB reactor containing these nitrifying granules finally reached 1.5 kg-N/m(3)/day. Results suggested that the use of granules realizes the retention of a large amount of nitrifying bacteria in the reactor, which guarantees a highly efficient nitrification. (C) 2003 Elsevier Ltd. All rights reserved.

    DOI

  • In situ PCR for visualizing distribution of a functional gene "amoA" in a biofilm regardless of activity

    T Hoshino, S Tsuneda, A Hirata, Y Inamori

    JOURNAL OF BIOTECHNOLOGY   105 ( 1-2 ) 33 - 40  2003年10月  [査読有り]

     概要を見る

    In this study, ammonia-oxidizing bacteria present in biofilms resulting from a nitrifying reactor were detected by both a conventional FISH technique and an original in situ PCR technique. Both techniques showed that ammonia-oxidizing bacteria were found near the surface of the biofilms. However, after the biofilm had been exposed to 2 weeks of ammonia starvation, ammonia-oxidizing bacteria present in the biofilm could not be detected by fluorescence in situ hybridization (FISH) because they did not have sufficient copies of rRNA. In contrast, ammonia-oxidizing bacteria could be detected by in situ PCR with strong signal. It was thus demonstrated that a cell possessing a specific functional gene is detectable by in situ PCR regardless of its activity. (C) 2003 Elsevier B.V. All rights reserved.

    DOI

  • スラグウールを付着担体とする固定床型硫酸還元バイオリアクターによる希薄廃水からのカドミウム回収

    林浩志, 勝賀瀬暢一, 常田聡, 平田彰, 佐々木弘

    資源と素材   119 ( 9 ) 559 - 563  2003年09月

  • Photooxidation of PCE in Gas Phase in UV-Bubble Column Reactor with H2O2

    D. Alibegic, S. Tsuneda, A. Hirata

    Water Intelligence Online    2003年09月

  • Influence of Growth Phase on Bacterial Cell Electrokinetic Characteristics Examined by Soft Particle Electrophoresis Theory

    H. Hayashi, H. Seiki, S. Tsuneda, A. Hirata, H. Sasaki

    J. Colloid Interface Sci.   264 ( 2 ) 565 - 568  2003年09月

  • Adsorption Effect on the Dynamic Response of a Biochemical Reaction in a Biofilm Reactor for Wastewater Treatment

    S. Tsuneda, Y. Inoue, J. Auresenia, A. Hirata

    ENGINEERING IN LIFE SCIENCES   3 ( 9 ) 371 - 375  2003年09月  [査読有り]

  • Oxidation of tetrachloroethylene in a bubble column photochemical reactor applying the UV/H2O2 technique

    D Alibegic, S Tsuneda, A Hirata

    CANADIAN JOURNAL OF CHEMICAL ENGINEERING   81 ( 3-4 ) 733 - 740  2003年06月  [査読有り]

     概要を見る

    Mass transfer of tetrachloroethylene (PCE) gas, followed by a free-OH radical reaction in the liquid phase, was studied in a bubble column reactor equipped with a UV light source and containing aqueous H2O2 as the reacting medium. Degradation of PCE in the liquid phase was found to follow pseudo-first-order kinetics, and the optimal ratio of H2O2/PCE leading to the highest oxidation rate could be successfully obtained from the analysis of the steady-state OH radical concentration. Absorption of PCE gas was in the kinetic slow regime and could be predicted based on the ratio of the apparent rate constant of PCE liquid degradation to the volumetric mass transfer coefficient (kapp/K(L)a). The presence of small amounts of PCE in the liquid bulk had positive effect on the mass transfer over the range studied and need to be, taken into account.

  • Extracellular polymeric substances responsible for bacterial adhesion onto solid surface

    S Tsuneda, H Aikawa, H Hayashi, A Yuasa, A Hirata

    FEMS MICROBIOLOGY LETTERS   223 ( 2 ) 287 - 292  2003年06月  [査読有り]

     概要を見る

    The influence of extracellular polymeric substances (EPS) on bacterial cell adhesion onto solid surfaces was investigated using 27 heterotrophic bacterial strains isolated from a wastewater treatment reactor. Cell adhesion onto glass beads was carried out by the packed-bed method and the results were discussed in terms of the amount of each EPS component produced and cell surface characteristics such as zeta potential and hydrophobicity. Protein and polysaccharides accounted for 75-89% of the EPS composition, indicating that they are the major EPS components. Among the polysaccharides, the amounts of hexose, hexosamine and ketose were relatively high in EPS-rich strains. For EPS-poor strains, the efficiency of cell adhesion onto glass beads increased as the absolute values of zeta potential decreased, suggesting that electrostatic interaction suppresses cell adhesion efficiency. On the other hand, the amounts of hexose and pentose exhibited good correlations with cell adhesiveness for EPS-rich strains, indicating that polymeric interaction due to the EPS covering on the cell surface promoted cell adhesion. It was concluded that, if the EPS amount is relatively small, cell adhesion onto solid surfaces is inhibited by electrostatic interaction, and if it is relatively large, cell adhesion is enhanced by polymeric interaction. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

    DOI

  • Influence of Extracellular Polymers on Electrokinetic Properties of Heterotrophic Bacterial Cells Examined by Soft Particle Electrophoresis Theory

    S. Tsuneda, J. Jung, H. Hayashi, H. Aikawa, A. Hirata, H. Sasaki

    Colloids and Surf. B: Biointerfaces   29 ( 2,3 ) 181 - 188  2003年05月

  • 中空糸メンブレンを用いた新しい水処理技術

    寺田昭彦, 日比谷和明, 常田聡, 平田彰

    水処理技術   44 ( 4 ) 153 - 164  2003年04月

  • High-speed recovery of antimony using chelating porous hollow-fiber membrane

    SY Nishiyama, K Saito, K Saito, K Sugita, K Sato, M Akiba, T Saito, S Tsuneda, A Hirata, M Tamada, T Sugo

    JOURNAL OF MEMBRANE SCIENCE   214 ( 2 ) 275 - 281  2003年04月  [査読有り]

     概要を見る

    A porous hollow-fiber membrane containing an iminodiethanol (IDE) group as the chelate-forming group was applied to the recovery of antimony in the permeation mode. An antimony solution was forced to permeate through the pores of the chelating porous hollow-fiber membrane, driven by a transmembrane pressure. The membrane with a thickness of 0.7 mm and a porosity of 70% had an immodiethanol group of 1.6 mol/kg of the membrane and a water flux of 0.95 m/h at 0.1 MPa and 298 K. The breakthrough curves of antimony overlapped irrespective of the permeation rate of the antimony solution ranging from 2 to 20 ml/min, i.e. the residence time across the membrane thickness ranging from 3.4 to 0.34 s, because of negligible diffusional mass-transfer resistance of the ionic species of antimony to the iminodiethanol group. At antimony concentrations below 10 mg/l (pH 4.0), a linear adsorption isotherm was obtained. The adsorbed antimony was quantitatively eluted by permeation of 2 M hydrochloric acid through the pores of the membrane. (C) 2002 Elsevier Science B.V. All rights reserved.

    DOI

  • 独立栄養細菌を用いた硝化・脱窒同時進行型反応場の開発

    青井議輝, 白政優子, 常田聡, 平田彰

    用水と廃水   45 ( 2 ) 129 - 133  2003年02月

  • UV-bubble column reactor (UV-BCR) for photolytic removal of tetrachloroethylene (PCE) from the vapor phase: Methodological approach

    D Alibegic, S Tsuneda, A Hirata

    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN   36 ( 2 ) 178 - 186  2003年02月  [査読有り]

     概要を見る

    Chlorinated volatile organic compounds (CVOCs) such as tri- and tetrachloroethylene (TCE and PCE) are common contaminants of ground water and soil. Numerous studies have been carried out with the long-term objective of the development of efficient, destructive on-site technologies for their removal. The so-called advanced oxidation processes (AOPs) were applied in the liquid and in the gas, but were shown to have limited application. In the liquid phase the efficiency was limited due to the presence of OH radical scavengers and UV light absorbers; and in the gas phase due to the production of stable intermediates.
    A new photochemical reactor system is described, in which the polluted air (from the air stripper or SVE unit) is absorbed into a bubble column reactor equipped with the UV light (UV-BCR) containing only distilled water and H2O2 as a reacting medium. The experiments showed that the oxidation of model pollutant PCE in a liquid phase occurred approximately 6 times faster in an OH radical scavenger-free environment compared to the experiments in which the OH radical scavenger concentration was adjusted to a level usually found in ground waters. It was also observed, that for the certain PCE concentration, there exists an optimal hydrogen peroxide concentration above and below which the rate is reduced and could be predicted by the kinetic model under operational conditions of this work. For the experiments in which PCE gas was absorbed into the UV-BCR, the influences of the two critical parameters, gas flow rate and the hydrogen peroxide concentration, were investigated using the experimental design methodology. There has been observational evidence of the efficiency of the process (cca 75%-80% PCE gas removal efficiency in one flow through the UV-BCR) but the operational parameters still need to be optimized.

  • Nitrogen removal characteristics and biofilm analysis of a membrane-aerated biofilm reactor applicable to high-strength nitrogenous wastewater treatment

    A Terada, K Hibiya, J Nagai, S Tsuneda, A Hirata

    JOURNAL OF BIOSCIENCE AND BIOENGINEERING   95 ( 2 ) 170 - 178  2003年02月  [査読有り]

     概要を見る

    A membrane-aerated biofilm reactor (MABR) capable of simultaneous nitrification and denitrification in a single reactor vessel was developed to investigate the characteristics of nitrogen removal from high-strength nitrogenous wastewater, and biofilm analysis using microelectrodes and the fluorescence in situ hybridization (FISH) technique was performed. Mean removal percentages of total organic carbon (TOC) and nitrogen were 96% and 83% at removal rates of 5.76 g-C m(-2) d(-1) and 4.48 g-N m(-2) d(-1), respectively. For stable removal efficiency, constant washing of the biofilm was needed. Dissolved oxygen microelectrode measurement revealed that the biofilm thickness was about 1600 mum, and that oxygen penetrated about 300 to 700 mum from the outer surface of the membrane. Furthermore, FISH analysis revealed that ammonia-oxidizing bacteria (AOB) were located near the outer surface of the membrane, whereas other bacteria were located from the inner to the outer part of the biofilm. Combining these results demonstrated that simultaneous nitrification and denitrification occurred in the biofilm of the MABR system. In addition, stoichiometric analysis revealed that after 130 d the free ammonia (FA) concentration ranged within the concentration causing inhibition of the growth of nitrite oxidizing bacteria (NOB) and that AOB consumed 86% of the oxygen supplied through the intra-membrane. These results indicate that nitrogen removal not via nitrate but via nitrite was mainly achieved in the MABR system.

  • Simultaneous nitrification and denitrification by controlling vertical and horizontal microenvironment in a membrane-aerated biofilm reactor

    K Hibiya, A Terada, S Tsuneda, A Hirata

    JOURNAL OF BIOTECHNOLOGY   100 ( 1 ) 23 - 32  2003年01月  [査読有り]

     概要を見る

    Nitrogen and carbon components in domestic modified wastewater were completely removed by simultaneous nitrification and denitrification using a membrane-aerated biofilm reactor where biofilm was fixed on a hollow-fiber membrane. To measure the spatial distribution of pH, ammonium and nitrate ions and to observe microbes inside the biofilm fixed on the membrane, microelectrodes and the fluorescence in situ hybridization (FISH) method were applied. Due to plug flow in the vertical direction (from the bottom to the top of the reactor), ammonium nitrogen was gradually removed and negligible nitrate nitrogen was detected throughout the reactor. FISH revealed that ammonia-oxidizing bacteria were mainly distributed inside the biofilm and other bacteria, which included denitrifying bacteria, were mainly distributed outside the biofilm and over the suspended sludge. In order to characterize bacterial activity in the vertical direction of the reactor, nitrification rates at lower, central and upper points were calculated using microelectrode data. The nitrification rate at the lower point was 7 and 125 times higher than those at the central and upper points, respectively. These results show that the removal of carbon and nitrogen compounds was accomplished efficiently by using various kinds of bacteria distributed vertically and horizontally in a single reactor. (C) 2002 Elsevier Science B.V. All rights reserved.

  • Comparison of detection specificity of nitrifying bacteria in biofilm using fluorescence in situ hybridization and in situ fluorescent antibody methods

    N Noda, Y Ebie, M Matsumura, S Tsuneda, A Hirata, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   47 ( 5 ) 129 - 132  2003年  [査読有り]

     概要を見る

    The in situ fluorescent antibody and fluorescence in situ hybridization (FISH) methods are very useful in the in situ detection of specific bacteria like nitrifiers in a biofilm. In this study, simultaneous staining using the FISH and in situ fluorescent antibody methods was examined. As a result, no specific fluorescence was observed with either method when FISH was performed followed by the in situ fluorescent antibody method; however, when the in situ fluorescent antibody method was performed first followed by FISH, specific fluorescence was observed in both cases. Moreover, it was suggested that the detection specificities of FISH and the in situ fluorescent antibody method are almost identical.

  • Quinone Profiles Reflecting Population Dynamics of Denitrifying Phosphate-Accumulating Organisms

    Satoshi Tsuneda, Takashi Ohno, Johwan Ahn, Tomotaka Daidou, Akira Hirata

    Microbes and Environments   18 ( 2 ) 69 - 73  2003年

     概要を見る

    Selective enrichment of phosphate-accumulating organisms (PAOs) and denitrifying phosphate-accumulating organisms (DNPAOs) was conducted using a sequencing batch reactor (SBR). To elucidate biomarkers for DNPAOs, quinone profiles were monitored during selective enrichment. As a result, a high correlation between the mole fraction of ubiquinone with eight isoprene units (Q-8) and anoxic phosphate uptake ability was observed, indicating that Q-8 was one of the biomarkers for DNPAOs. In addition, the mole ratio of ubiquinones to menaquinones (Q/MK) increased throughout this selective enrichment. © 2003, Japanese Society of Microbial Ecology &amp
    The Japanese Society of Soil Microbiology. All rights reserved.

    DOI

  • Effects of SRT and DO on N2O reductase activity in an anoxic-oxic activated sludge system

    N Noda, N Kaneko, M Milkami, Y Kimochi, S Tsuneda, A Hirata, M Mizuochi, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   48 ( 11-12 ) 363 - 370  2003年  [査読有り]

     概要を見る

    Nitrous oxide (N2O) is emitted from wastewater treatment processes, and is known to be a green house gas contributing to global warming. It is thus important to develop technology that can suppress N2O emission. The effects of sludge retention time (SRT) and dissolved oxygen (DO) on N2O emission in an anoxic-oxic activated sludge system were estimated. Moreover, the microbial community structure in the sludge, which plays an important role in N2O Suppression, was clarified based on nitrous oxide reductase (nosZ) gene analysis by molecular biological techniques. The results showed that under low SRT conditions, nitrification efficiency was reduced and the N2O emission rate in the oxic reactors was increased. It was also observed that N2O emission was enhanced under low DO conditions, where the available oxygen is insufficient for nitrification. Moreover, molecular analysis revealed that the clones identified in this study were closely related to Ralstonia eutropha and Paracoccus denitrificans. The fact that the identified sequences are not closely related to known culturable denitrifier nosZ sequences indicates a substantial in situ diversity of denitrifiers contributing to N2O suppression, which are not reflected in the cultivatable fraction of the population. The further application of these new molecular techniques should serve to enhance our knowledge of the microbial community of denitrifying bacteria contributing to N2O suppression in wastewater treatment systems.

  • Degradation of xenobiotic substances using sulfate-reducing bacteria in a UASB reactor

    S Tsuneda, T Shiono, K Nakamura, T Dogan, A Hirata

    WATER SCIENCE AND TECHNOLOGY   48 ( 11-12 ) 227 - 234  2003年  [査読有り]

     概要を見る

    An upflow anaerobic sludge blanket (UASB) reactor was successfully applied to continuous degradation of ferric ethylene diamine tetraacetate (Fe-EDTA) as a typical xenobiotic substance contained in photo-processing wastewater. The sludge in the UASB reactor had an abundance of sulfate-reducing bacteria (SRB), which had been anaerobically cultivated in a sulfate-rich culture medium including Fe-EDTA and yeast-extract as the carbon sources. Since the prominent reductions of Fe-EDTA and sulfate ion were observed, the contribution of SRB to Fe-EDTA degradation in the UASB reactor was confirmed. The aggregated sludge in the UASB reactor became gradually large reaching steady state with an equivalent diameter of 60-90 mum after 124 days operation. An increase of the amount of yeast extract addition to feed solution improved the Fe-EDTA removal efficiency up to 90%. Moreover, the combination of ozone treatment with SRB treatment further improved removal efficiency of total organic carbon (TOC) in an actual photo-processing wastewater composed of fixing and developing wastes.

  • 脱窒性リン蓄積細菌を利用した新しい高度排水処理プロセス

    常田聡, 安祚煥, 大道智孝, 大野高史, 平田彰

    水環境学会誌   25 ( 12 ) 751 - 755  2002年12月

  • 有用微生物固定化技術と排水高度処理への応用

    常田聡

    最近の化学工学   54   128 - 141  2002年11月

  • 放射線グラフト重合法で作製した多孔性膜を用いた金属イオンの高効率捕集

    斎藤加織, 斎藤恭一, 杉田和之, 常田聡, 平田彰, 須郷高信

    科学と工業   76 ( 11 ) 565 - 571  2002年11月

  • Dynamic Modeling and Simulation of a Three-Phase Fluidized Bed Batch Process for Wastewater Treatment

    S. Tsuneda, J. Auresenia, T. Morise, A. Hirata

    Process Biochem.   38 ( 4 ) 599 - 604  2002年11月

  • 吸着脱リン法を導入した資源回収型リン除去技術

    高井智丈, 宮坂章, 稲森悠平, 小松央子, 小沼和博, 中川和哉, 常田聡

    用水と廃水   44 ( 7 ) 604 - 610  2002年07月

  • Transformation of phosphorus and relevant intracellular compounds by a phosphorus-accumulating enrichment culture in the presence of both the electron acceptor and electron donor

    J Ahn, T Daidou, S Tsuneda, A Hirata

    BIOTECHNOLOGY AND BIOENGINEERING   79 ( 1 ) 83 - 93  2002年07月  [査読有り]

     概要を見る

    This study was conducted to obtain a better insight into the metabolic behavior of denitrifying phosphate-accumulating organisms relative to the transformations of relevant intracellular compounds as well as phosphorus and nitrate for enhanced biological phosphorus removal under different combinations of electron acceptor (oxygen or nitrate) and electron donor (acetate). Under anoxic conditions, the amount of polyhydroxybutyrate (PHB) produced per acetate taken up considerably increased with the increasing amount of nitrate reduced whereas the amounts of nitrate reduced and phosphorus released per acetate taken up remained almost constant. However, glycogen utilization occurred during PHB production and then was again observed in response to the initial supplementation of acetate after glycogen accumulation was transiently observed during anoxic phosphorus uptake using nitrate as an electron acceptor. On the other hand, under subsequent aerobic conditions, the additional supplementation of acetate again caused aerobic phosphorus release and PHB production, which showed that PHB production was associated with polyphosphate cleavage regardless of electron acceptor conditions. In contrast to anoxic conditions, glycogen accumulation was observed during PHB production. Based on these observations, the preliminary model for the metabolic behavior of denitrifying phosphate-accumulating organisms was proposed and could well account for the complex transformations of PHB and glycogen together with phosphorus release in the presence of acetate under different electron acceptors. (C) 2002 Wiley Periodicals, Inc.

    DOI

  • Kinetic model for dynamic response of three-phase fluidized bed biofilm reactor for wastewater treatment

    S Tsuneda, J Auresenia, Y Inoue, Y Hashimoto, A Hirata

    BIOCHEMICAL ENGINEERING JOURNAL   10 ( 1 ) 31 - 37  2002年02月  [査読有り]

     概要を見る

    Step changes in inlet concentration has been introduced into the completely mixed three-phase fluidized bed biofilm reactor treating simulated domestic wastewater to study the dynamic behavior of the system and to establish the suitable kinetic model from the response curve. Three identical reactors having different biomass volumes were operated in parallel. It was found that the response curves showed second-order characteristics, and thus at least two first-order differential equations are necessary to simulate the substrate and biomass response curves. Nonlinear regression analysis was performed using different types of rate equations and their corresponding kinetic parameters were used to simulate the theoretical response curve using the Runge-Kutta numerical integration method. As a result, although various types of conventional biokinetic models such as Monod, Haldane and Andrew types were examined, all the theoretical substrate response curves underestimated time constants compared to the actual substrate response plots. On the other hand, the theoretical curve of the kinetic model that incorporates adsorption term has best fit to the actual response in most of the cases. Thus, it was concluded that adsorption of substrate onto biofilm and carrier particles has significant effect on he dynamic response in biofilm processes. (C) 2002 Elsevier Science B.V. All rights reserved.

  • Three-dimensional immobilization of bacterial cells with a fibrous network and its application in a high-rate fixed-bed nitrifying bioreactor

    H Hayashi, M Ono, S Tsuneda, A Hirata

    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN   35 ( 1 ) 68 - 75  2002年01月  [査読有り]

     概要を見る

    A novel technique of immobilizing nitrifying bacteria using fibrous material, the three-dimensional immobilization with a fibrous network (3-D IFN), is proposed and its use in a high-rate nitrifying bioreactor is investigated. The fibrous carrier employed is ferro-nickel fibrous slag (FS), which is industrial solid waste from a ferro-nickel electrosmelting process. Since cell immobilization with FS is readily carried out within 90 seconds, this method is by far more rapid than any other cell immobilization techniques. A fixed-bed nitrifying reactor packed with cell-immobilizing FS is examined by both batch-mode and continuous feeding tests. By controlling the circulation flow rate, the transport of dissolved oxygen to the immobilized cells is improved, which is a distinct characteristic of this reactor. The continuous feeding test revealed that the ammonia removal rate of the reactor reached 6.5 kg-N/(m(3)-reactor)/d, which was extremely high compared with that of the conventional fixed-bed reactor for wastewater treatment. It is demonstrated that the 3-D IFN is a simple yet effective cell immobilization technique that can be successfully used in a high-rate nitrifying reactor.

  • Characterization of denitrifying phosphate-accumulating organisms cultivated under different electron acceptor conditions using polymerase chain reaction-denaturing gradient gel electrophoresis assay

    J Ahn, T Daidou, S Tsuneda, A Hirata

    WATER RESEARCH   36 ( 2 ) 403 - 412  2002年01月  [査読有り]

     概要を見る

    To investigate the characteristics and the microbial diversity of denitrifying phosphate-accumulating organisms (DNPAOs) that are capable of conducting enhanced biological phosphorus removal (EBPR) using nitrate as electron acceptor, three sequencing batch reactors were operated under three different electron acceptor conditions, i.e., only oxygen, oxygen together with nitrate and only nitrate. Based on the chemical analysis concerning the biochemical transformation of each reactor, it was found that phosphate-accumulating organisms responsible for EBPR consisted of at least three populations including DNPAOs, and that the microbial community structure was changed according to the electron acceptor conditions. Also, the sludge cultivated with oxygen together with nitrate showed a drastic increase in the amount of phosphorus uptake under anoxic conditions, which suggested that a proportion of DNPAOs capable of utilizing nitrate under aerobic conditions were present.
    On the other hand, the change in microbial community structure depending on the type of electron acceptor was demonstrated by the analysis of the results of denaturing gradient gel electrophoresis of polymerase chain reaction-amplified 16S ribosomal DNA fragments. It was found that the bacteria commonly contained in all the reactors were Rhodocyclus sp. (96% identity) and Dechlorimonas sp. (97% identity) that belonged to the beta subclass of Proteobacteria, on the basis of the analysis of the sequence excised from DGGE bands and the determination of phylogenetic affiliation. However, only the presence of Rhodocyclus sp. in all the reactors was demonstrated by fluorescent in situ hybridization analysis. (C) 2002 Elsevier Science Ltd. All rights reserved.

  • Real-time monitoring of ammonia-oxidizing activity in a nitrifying biofilm by amoA mRNA analysis

    Y Aoi, Y Shiramasa, S Tsuneda, A Hirata, A Kitayama, T Nagamune

    WATER SCIENCE AND TECHNOLOGY   46 ( 1-2 ) 439 - 442  2002年  [査読有り]

     概要を見る

    Ammonia monooxygenase encoding mRNA (amoA mRNA) transcription in the wastewater treatment process was investigated using reverse transcription PCR (RT-PCR) as the model indicating specific function and activity in nitrifying processes. The dynamic response of amoA mRNA transcription and ammonia-oxidizing activity to the change of environmental conditions such as pH and concentration of ammonia was examined to determine the inductive factor and the inhibitor for amoA mRNA expression. Furthermore, we semiquantitatively investigated the response of amoA mRNA transcription to the pH fluctuation in a continuous fed nitrifying reactor. AS a result, amoA mRNA oriented analysis enabled real-time assay of ammonia-oxidizing activity within 2 h as a response time. In contrast, rRNA and amoA encoding DNA were constantly detected at almost the same amount throughout the experiment. mRNA transcription was regulated by the many environmental conditions: ammonia seems to be one of the strong inducers for transcription of amoA mRNA, whereas low pH seems to be a strong inhibitor. These factors simultaneously affected the mRNA transcription and enzymatic activity leading to the complex phenomena of ammonia-oxidizing activity and amoA mRNA transcription in the continuous feeding reactors.

  • PCR-DGGE analysis of denitrifying bacteria in a metallurgic wastewater treatment process

    N Noda, S Yoshie, T Miyano, S Tsuneda, A Hirata, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   46 ( 1-2 ) 333 - 336  2002年  [査読有り]

     概要を見る

    The wastewater generated from the processes of recovering precious metals from industrial wastes contains high concentrations of acids such as nitric acid and of salts. Biological nitrogen removal from this wastewater was attempted by using a circulating bioreactor system equipped with an anoxic packed bed or an anoxic fluidized bed and an aerobic three-phase fluidized bed. The system was found to effectively remove nitrogen from the diluted wastewater (T-N; 1,000-4,000 mg litre(-1)). The microbial population structure of activated sludge in an anoxic reactor was analyzed by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA (rDNA) fragments. DGGE analysis under different operating conditions demonstrated the presence of some distinguishable bands in the separation pattern, which were most likely derived from many different species constituting the microbial communities. Furthermore, the population diversity varied in accordance with the nitrate-loading rate, water temperature and reactor condition. Some major DGGE bands were excised, reamplified and directly sequenced. It was revealed that the dominant population in the anoxic reactor were affiliated with the beta subclass of the class Proteobacteria.

  • Detection and quantification of expression of amoA by competitive reverse transcription-PCR

    Y Ebie, H Miura, N Noda, M Matsumura, S Tsuneda, A Hirata, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   46 ( 1-2 ) 281 - 288  2002年  [査読有り]

     概要を見る

    Ammonia oxidation by chemolithoautotrophic ammonia-oxidizing bacteria is an important step in the biological nitrogen removal process. The first conversion step, the oxidation of ammonia to hydroxylamine is catalyzed by ammonia monooxygenase (AMO). To investigate the activity of ammonia oxidation, mRNA (designated as amoA) encoding a subunit of AMO was quantified by competitive reverse transcription (RT)-PCR. As a result, it was possible to detect and quantify amoA expression in cultured Nitrosomonas europaea and even complex microbial communities such as nitrifying bacterial aggregates by competitive RT-PCR. It was estimated that amoA concentration in cultured N. europaea was 2.3 x 10(8) copies.ml(-1). Additionally, it was calculated that the copy number of amoA in nitrifying bacterial aggregates was 1.0 x 10(12) copies.ml(-1) (5.1 x 10(10) copies.mg(-1).dry weight). On the other hand, amoA expression in the natural activated sludge in a household Gappei-Johkaso was undetectable, whereas 16S rRNA of ammonia-oxidizing bacteria was detected by RT-PCR. Then, four days cultivation of this sludge in inorganic artificial wastewater resulted in increasing amoA expression to a quantifiable amount by competitive RT-PCR. In conclusion, the competitive RT-PCR was effective to investigate the expression of amoA as an indicator of ammonia oxidation activity by autotrophic ammonia-oxidizing bacteria.

  • Inhibition effect of chlorine ion on hydroxyl radical generation in UV-H2O2 process

    S Tsuneda, Y Ishihara, M Hamachi, A Hirata

    WATER SCIENCE AND TECHNOLOGY   46 ( 11-12 ) 33 - 38  2002年  [査読有り]

     概要を見る

    UV-H2O2 process is widely used as an advanced oxidation process (AOP) for the treatment of chlorine volatile organic compounds (CVOCs) such as dichloromethane (DCM) with strong oxidativity of hydroxyl radical generated from photolysis of H2O2. The result of DCM degradation rate at different initial concentrations in UV-H2O2 processes indicated the inhibition effect of produced chlorine ions on DCM oxidation processes, because the first-order degradation rate constant increased with lower initial concentrations. A spin trapping adduct of hydroxyl radical with 5,5-dimethyl-1-pyrroline-n-oxide (DMPO) was quantified by ESR spectrometer after UV irradiation in the presence of different amounts of chlorine ion, and as a result, the chlorine ion was found to act as a hydroxyl radical scavenger, which resulted in decreasing DCM degradation rate. An UV-H2O2 reactor equipped with ion exchangers for removing chlorine ion achieved higher DCM degradation rate than that without ion exchangers.

  • Community analysis of nitrifying bacteria in. an advanced and compact Gappel-Johkasou by FISH and PCR-DGGE

    Y Ebie, M Matsumura, N Noda, S Tsuneda, A Hirata, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   46 ( 11-12 ) 105 - 111  2002年  [査読有り]

     概要を見る

    Fluorescent in situ hybridization (FISH) method with 16S rRNA-targeted oligonucleotide probes was used for quantitative estimation of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in a Johkasou. Although the occupation ratios of AOB and NOB increased as nitrification progressed, about one month later, the occupation ratios decreased, despite showing good nitrification ability. Furthermore, even when urea was added to the feeding wastewater to raise the amount of T-N, the occupation ratios of both nitrifying bacteria remained constant. For further investigation, denaturing gradient gel electrophoresis (DGGE) was used to study the community structure of AOB in the Johkasou. As a result, DGGE band patterns and following sequence analysis revealed that the community structure of AOB was complicated and changed during this experiment. It was suggested that even if the occupation ratio of AOB to eubacteria was constant, the majorities of AOB were changed through temperature and load fluctuation. The combination of FISH and PCR-DGGE provides new information that was not available by conventional cultivation based methods.

  • Characterization of microbial community in nitrogen removal process of metallurgic wastewater by PCR-DGGE

    S Yoshie, N Noda, T Miyano, S Tsuneda, A Hirata, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   46 ( 11-12 ) 93 - 98  2002年  [査読有り]

     概要を見る

    The metallurgic wastewater generated from the processes of recovering precious metals from industrial wastes contains high concentrations of nitrogen compounds such as ammonia and nitric acid and of salts such as sodium chloride and sodium sulfate. Biological nitrogen removal from this wastewater was attempted by a circulating bioreactor system equipped with an anoxic packed bed and an aerobic fluidized bed. The anoxic packed bed of this system was found to effectively remove nitrite and nitrate from the wastewater by denitrification at a removal ratio of 97%. As a result of denitrification activity tests at various NaCl concentrations, the sludge obtained from the anoxic packed bed exhibited accumulation of nitrite at 5.0 and 8.4% NaCl concentrations, suggesting that the reduction of nitrite is the key step in the denitrification pathway under hypersaline conditions. The microbial community analysis by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA (rDNA) fragments revealed that the community diversity varied in accordance with water temperature, nitrate-loading rate and ionic strength. When particular major DGGE bands were excised, reamplified and directly sequenced, the dominant species in the anoxic packed bed were affiliated with the beta and gamma subclasses of the class Proteobacteria such as Alcaligenes defragrans and Pseudomonas spp., respectively.

  • 地域環境保全のための嫌気好気生物膜法による畜産排水の高度処理 〜脱窒性リン蓄積細菌の優占化技術と栄養塩除去プロセスへの応用〜

    常田聡, 安祚煥, 大道智孝, 平田彰

    環境科学総合研究所年報   20   7 - 11  2001年12月

  • 貴金属回収工程から排出される硝酸含有廃水の生物学的窒素除去

    常田聡, 宮野知子, 小川知幸, 吉江幸子, 平田 彰, 大田有香, 磯部公信, 稲垣 肇, 片山 卓

    日本水処理生物学会誌   37 ( 4 ) 141 - 149  2001年12月

  • Selection and dominance mechanisms of denitrifying phosphate-accumulating organisms in biological phosphate removal process

    J Ahn, T Daidou, S Tsuneda, A Hirata

    BIOTECHNOLOGY LETTERS   23 ( 24 ) 2005 - 2008  2001年12月  [査読有り]

     概要を見る

    A sequencing batch reactor under different electron acceptor conditions was operated serially to investigate the selection and dominance mechanisms of denitrifying phosphate-accumulating organisms (DNPAOs) in a biological nutrient removal process. The presence of a small amount of NO3- at the start of the anaerobic phase stimulated the selection of DNPAOs in an anaerobic/aerobic system, and switching O-2 to NO3- as an electron acceptor enhanced the activity of anoxic phosphate uptake.

  • Kinetics of tetrachloroethylene (PCE) gas degradation and byproducts formation during UV/H2O2 treatment in UV-bubble column reactor

    D Alibegic, S Tsuneda, A Hirata

    CHEMICAL ENGINEERING SCIENCE   56 ( 21-22 ) 6195 - 6203  2001年11月  [査読有り]

     概要を見る

    The UV/H2O2 process is commonly used for the remediation of drinking and groundwater pollution with chlorinated volatile organic compounds. In direct treatment, its efficiency can be lowered in the presence of radical scavengers and/or UV light absorbers. This research is focused on the improvement of the UV/H2O2 photolytic process, due to the reduction of OH radical scavengers and UV absorbers in the reacting system. Degradation of tetrachloroethylene (PCE) gas, which was absorbed into a bubble column reactor equipped with UV light (UV-BCR), containing distilled water and H2O2, as the reacting medium, was studied in a one flow-through mode. Degradation of PCE in the liquid phase was found to follow pseudo-first-order kinetics and apparent rate constants in the order of 0.02 s(-1) have been observed. An absorption-reaction model based on slow reaction in the bulk liquid was proposed, and it fitted the experimental data reasonably well. However, when sequence making internal (designed as to prolong the gas pathway through the reactor) was in the system in addition to the relatively high PCE concentrations (500 ppm), production of the byproduct chloroform was observed, indicating that some reaction might have occurred in the gas phase. The addition of term for a reaction in the gas phase was able to account for the reaction due to direct absorption of PCE. (C) 2001 Elsevier Science Ltd. All rights reserved.

  • Direct detection by in situ PCR of the amoA gene in biofilm resulting from a nitrogen removal process

    T Hoshino, N Noda, S Tsuneda, A Hirata, Y Inamori

    APPLIED AND ENVIRONMENTAL MICROBIOLOGY   67 ( 11 ) 5261 - 5266  2001年11月  [査読有り]

     概要を見る

    Ammonia oxidation is a rate-limiting step in the biological removal of nitrogen from wastewater. Analysis of microbial communities possessing the amoA gene, which is a small subunit of the gene encoding ammonia monooxygenase, is important for controlling nitrogen removal. In this study, the amoA gene present in Nitrosomonas europaea cells in a pure culture and biofilms in a nitrifying reactor was amplified by in situ PCR. In this procedure, fixed cells were permeabilized with lysozyme and subjected to seminested PCR with a digoxigenin-labeled primer. Then, the amplicon was detected with an alkaline phosphatase-labeled antidigoxigenin antibody and HNPP (2-hydroxy-3-naphthoic acid-2'-phenylanilide phosphate), which was combined with Fast Red TR, and with an Alexa Fluor 488-labeled antidigoxigenin antibody. The amoA gene in the biofilms was detected with an unavoidable nonspecific signal when the former method was used for detection. On the other hand, the amoA gene in the biofilms was detected without a nonspecific signal, and the cells possessing the amoA gene were clearly observed near the surface of the biofilm when Alexa Fluor 488-labeled antidigoxigenin antibody was used for detection. Although functional gene expression was not detected in this study, detection of cells in a biofilm based on their function was demonstrated.

  • TOC removal of diethylene glycol mono-n-hexyl ether synthetic wastewater and 1,4-butanediol diglycidyl ether synthetic wastewater with H2O2/UV in a batch reactor

    WJ Hou, S Tsuneda, A Hirata

    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN   34 ( 10 ) 1279 - 1284  2001年10月  [査読有り]

     概要を見る

    Total organic carbon (TOC) removals of two synthetic wastewaters which contain diethylene glycol mono-n-hexyl ether (DIGME) and 1,4-butanediol diglycidyl ether (1,4-BDE) respectively as a main component, have been carried out by using hydrogen peroxide and ultraviolet irradiation (H2O2/UV). Experiments were carried out in a batch reactor with a low pressure UV lamp (500 W) irradiating ultraviolet at 254 nm and at 185 nm (5% of energy). The following results were obtained. (1) The complete TOC removals of the two synthetic wastewaters have been obtained. TOC removals of the two synthetic wastewaters are pseudo-first-order processes. (2) The removal rates of TOC of the two synthetic wastewaters were governed by the concentration of hydrogen peroxide added initially and the maximum pseudo-first-order rate constant and the optimum initial hydrogen peroxide concentration existed both in the two synthetic wastewaters. (3) The relation between the initial TOC concentration and the optimum initial hydrogen peroxide concentration exhibited linear in both synthetic wastewaters. The optimum initial hydrogen peroxide concentration in the TOC removal of the 1,4-BDE synthetic wastewater is higher than that of the DGME synthetic wastewater at the given initial TOC concentration. (4) The maximum pseudo-first-order rate constant increases with the decrease in the initial TOC concentration in both synthetic wastewaters. The maximum pseudo-first-order rate constant for the DGME synthetic wastewater is higher than that for the 1,4-BDE synthetic wastewater at the given initial TOC concentration. (5) The experimental results agree well with the theoretical consideration which has been previously proposed by authors (Hou et al., 2001c) while hydrogen peroxide concentration and TOC concentration in the wastewater were very high.

  • Rapid Recovery of Bacterial Cells from a Stable Dispersion by Heterocoagulation to a Fibrous Collector

    H. Hayashi, T. Nihei, M. Ono, S. Tsuneda, A. Hirata, H. Sasaki

    J. Colloid Interface Sci.   243 ( 1 ) 109 - 115  2001年10月

  • Efficient TOC removal of wastewater containing 1,2-naphthoquinone-2-diazido-5-sulfonic acid sodium salt with H2O2/UV in a batch reactor

    WJ Hou, S Tsuneda, A Hirata

    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN   34 ( 9 ) 1084 - 1090  2001年09月  [査読有り]

     概要を見る

    Total organic carbon (TOC) removals of the synthetic wastewater and of the raw industrial wastewater discharged from LSI photo-resist processing of which main component is 1,2-naphthoquinone-2-diazido-5-sulfonic acid sodium salt (abbreviation naphthoquinone-5), have been carried out by using hydrogen peroxide and ultraviolet irradiation (H2O2/UV). Experiments were carried out in a batch reactor with a low pressure UV lamp (500 W) irradiating ultraviolet of 254 nm and of 185 nm (5% of energy). The following results were obtained. (1) TOC removals of the synthetic wastewater and of the raw industrial wastewater are pseudo-first-order processes, and TOC shows zero in about ten and several hours. (2) The TOC removal rate of the wastewater was governed by the concentration of hydrogen peroxide initially added and by the maximum pseudo-first-order rate constant and the optimum initial hydrogen peroxide concentration both existed in the synthetic wastewater and in the raw industrial wastewater. (3) The relation between the initial TOC concentration and the optimum initial hydrogen peroxide concentration exhibited linear both in the synthetic wastewater and in the raw industrial wastewater. The optimum initial hydrogen peroxide concentration in TOC removal of the raw industrial wastewater is same as that in the synthetic wastewater at the given initial TOC concentration. (4) The maximum pseudo-first-order rate constant increases with the decrease in the initial TOC concentration both in the synthetic wastewater and in the raw industrial wastewater. (5) A theoretical consideration was carried out and could explain with experimental results.

  • Visualization of Microscale Distribution of Nitrifying Bacteria in Biofilms Formed in Various Type Wastewater Treatment Processes

    Y. Aoi, T. Miyoshi, T. Okamoto, S. Tsuneda, A. Kitayama, E. Kayano, T. Nagamune, A. Hirata

    Advances in Water and Wastewater Treatment Technology -Molecular Technology, Nutrient Removal, Sludge Reduction, and Environmental Health-     141 - 151  2001年08月

  • TOC removal of 2,4,5-trichlorophenol synthetic wastewater with H2O2/UV in a batch reactor

    WJ Hou, S Tsuneda, A Hirata

    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN   34 ( 8 ) 1049 - 1051  2001年08月  [査読有り]

     概要を見る

    2,4,5-Trichlorophenol (2,4,5-TCP) is one of the most toxic chlorophenols (CPs) and is very difficult to be biodegraded. The establishment of an appropriate treatment which is friendly to the earth environment for 2,4,5-TCP is an urgent matter to be solved. Total organic carbon (TOC) removal of the synthetic wastewater which contains 2,4,5-TCP at TOC of 405 g/m(3) has been carried out by using hydrogen peroxide and ultraviolet irradiation (H2O2/UV). Experiments were carried out in a batch reactor with a low pressure UV lamp (500 W) irradiating ultraviolet at 254 nm and at 185 nm (5%). The chemical compounds included in the synthetic wastewater have been completely removed in the presence of hydrogen peroxide. It was found that the optimum concentration of hydrogen peroxide, which was added initially, exists.

  • 包括型および付着型PEG担体で固定した硝化細菌の抗原抗体法による挙動解析

    野田尚宏, 蛯江美孝, 生田創, 常田聡, 平田彰, 松村正利, 角野立夫, 稲森悠平

    日本水処理生物学会誌   37 ( 2 ) 77 - 86  2001年06月

  • Direct Observation of Nitrifying Biofilms on Particles by Electron Microscopy

    A. Hirata, A. A. Meutia, S. Tsuneda

    Jpn. J. Water Treatment Biol.   37 ( 2 ) 87 - 92  2001年06月

  • 粉砕生ゴミを含む厨芥排水の生物処理

    常田聡, 丁在国, 中村和之, 日比谷和明, 平田彰

    用水と廃水   43 ( 5 ) 381 - 385  2001年05月

  • The Role of Electrokinetic Properties on Adhesion of Nitrifying Bacteria to Solid Surfaces

    H. Hayashi, S. Tsuneda, A. Hirata, H. Sasaki

    Studies in Surface Science and Catalysis   132   293 - 296  2001年05月

  • 火力発電所復水脱塩装置再生廃水からの生物学的窒素除去

    常田聡, 三好朋子, 平田彰

    日本水処理生物学会誌   37 ( 1 ) 9 - 17  2001年03月

  • アンチモン含有廃水の処理技術

    齋藤智宣, 常田聡, 斎藤恭一, 平田彰

    水処理技術   42 ( 3 ) 103 - 111  2001年03月

  • TOC removal of raw industrial wastewater from LSI photo-resist processing with H2O2/UV in a batch reactor

    WJ Hou, S Tsuneda, A Hirata

    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN   34 ( 3 ) 444 - 447  2001年03月  [査読有り]

     概要を見る

    The raw industrial wastewater from LSI photo-resist processing which contains 1,2-naphthoquinone-2-diazido-5-sulfonic acid sodium salt as a main component with high NaCl concentration (&gt;20 kg/m(3)), is very difficult to treat, The establishment of an appropriate treatment, which is friendly to the earth's environment for raw industrial wastewater is an urgent matter to be solved. Total organic carbon (TOC) removal of the raw industrial wastewater, which contains TOC at 8000 g-TOC/m(3), by using hydrogen peroxide and ultraviolet irradiation (H2O2/UV), has been carried out. Experiments were carried out in a batch reactor with a low pressure UV lamp (500 W) irradiating ultraviolet at 254 nm and at 185 nm (5 %), The chemical compounds included in the raw industrial wastewater have been removed completely in the presence of initial concentration of hydrogen peroxide of two times the stoichiometric ratio.

  • Enhancement of nitrifying biofilm formation using selected EPS produced by heterotrophic bacteria

    S Tsuneda, S Park, H Hayashi, J Jung, A Hirata

    WATER SCIENCE AND TECHNOLOGY   43 ( 6 ) 197 - 204  2001年  [査読有り]

     概要を見る

    The possibility of enhancing nitrifying biofilm formation rate with the aid of selected EPS produced by heterotrophic bacteria was investigated. When EPS production characteristics were examined for four kinds of heterotrophs isolated from a domestic wastewater treatment reactor, two strains obtained from biofilms (B1, B2) exhibited a higher polysaccharide production rate than those from suspended flocs (A1, A2). Among EPS components, the concentration of uronic acids gave a good correlation with flocculation ability, which suggests that acidic polysaccharides play a major role in bioaggregate formation. Addition of 1g/L D-glucuronic acid as an EPS substitute enhanced the homocoagulation rate of autotrophic Nitrosomonas europaea and altered its zeta potential from (n) over tilde 30.4mV to + 4.3mV, which indicates a possibility that particular EPS components produced by heterotrophs are utilized as neutralising reagents for nitrifying biofilm formation. Moreover, when heterotrophic isolates with Nitrobacter winogradskyi were cultured in batch with fabric supports, biofilm formed on the substratum, These experimental results suggest the application of selected EPS for enhancing nitrifying biofilm formation.

  • Soft particle analysis of bacterial cells and its interpretation of cell adhesion behaviors in terms of DLVO theory

    Hiroshi Hayashi, Satoshi Tsuneda, Akira Hirata, Hiroshi Sasaki

    Colloids and Surfaces B: Biointerfaces   22 ( 2 ) 149 - 157  2001年

     概要を見る

    The electrokinetic properties of two nitrifying strains, Nitrosomonas europaea and Nitrobacter winogradskyi, and three heterotrophic bacteria, Escherichia coli, Pseudomonas putida and Pseudomonas aeruginosa, were examined by electrophoretic mobility measurement and analyzed using the soft particle electrophoresis theory that is suitable for biological particles. The bacterial adhesion characteristics onto glass bead substratum were also evaluated by packed bed method. The mobility of the bacterial cells employed converged to a non-zero value as the ionic concentration increased, suggesting that the bacterial cells exhibited typical soft particle characteristics. Moreover, cell surface potentials based on the soft particle theory were lower than those estimated by the conventional Smoluchowski formula, i.e. zeta potential. Cell collision efficiencies onto glass beads (α0) were largely dependent on interfacial interaction, although almost electrically neutral P. aeruginosa did not follow that trend. From a comparison of α0 with DLVO interaction energy maximum (Vmax), it was assumed that heterocoagulation between cell and substratum at primary minimum potential took place under Vmax of 24-34 kT based on soft particle analysis. On the other hand, Vmax predictions using the Smoluchowski theory gave 81-223 kT, which indicated the possibility of overestimating electrostatic repulsive forces by the conventional Smoluchowski theory. Thus, the application of this new electrophoresis theory to several kinds of bacterial cells has led to the revision of the interpretation of bacterial mobility data and provided a more detailed understanding of the bacterial adhesion phenomenon. Copyright © 2001 Elsevier Science B.V.

    DOI

  • Biological nitrogen removal from industrial wastewater discharged from metal recovery processes

    A Hirata, Y Nakamura, S Tsuneda

    WATER SCIENCE AND TECHNOLOGY   44 ( 2-3 ) 171 - 179  2001年  [査読有り]

     概要を見る

    The wastewater generated from the processes of recovering precious metals from industrial wastes contains high concentrations of acids and alkalis such as nitric acid and aqueous ammonia, and of salts such as sodium chloride and sodium sulfate. Biological nitrogen removal from this wastewater was attempted by using a circulating bioreactor system equipped with an anaerobic packed bed and an aerobic three-phase fluidized bed. As a result of acclimating microorganisms with change of the hydraulic residence time, this system effectively removed nitrogen from diluted wastewater (T-N: from 2,000 to 4,000 g/m(3)), such that the total nitrogen concentration in the effluent met the sewage discharge control criteria in Japan (240 g/m(3)). The removal ratio of total nitrogen was 90% to 98% and that of ammonia was 80% to 92%. In addition, the characteristic equations for biological treatment were applied to this system on the assumption that both reactions of denitrification in the anaerobic reactor and nitrification in the aerobic reactor can be approximated to a first-order reaction. This simplified approach successfully led to a new analytical method for simulating the optimum volume ratio of anaerobic reactor to aerobic reactor for minimizing the total hydraulic residence time.

  • Microbial community analysis in the denitrification process of saline-wastewater by denaturing gradient gel electrophoresis of PCR-amplified 16S rDNA and the cultivation method

    Sachiko Yoshie, Naohiro Noda, Tomoko Miyano, Satoshi Tsuneda, Akira Hirata, Yuhei Inamori

    Journal of Bioscience and Bioengineering   92 ( 4 ) 346 - 353  2001年

     概要を見る

    The metallurgic wastewater generated from the processes of recovering precious metals from industrial wastes contains high concentrations of nitrogen compounds and salts. Biological nitrogen removal from this wastewater was attempted using a circulating bioreactor system equipped with an anaerobic packed bed or an anaerobic fluidized bed. The denitrification capability of the system with the anaerobic packed bed was more stable than that of the system with the anaerobic fluidized bed. The NOx removal rate of the anaerobic packed bed was as high as 97%. Microbial community analysis by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA (rDNA) fragments and the cultivation method revealed that the community diversity varied in accordance with wastewater composition such as the level of salinity and so on. Phylogenetic analysis suggested that the taxonomic affiliation of the dominant species in the anaerobic reactors was to the γ-Proteobacteria including Halomonadaceae species. The PCR-DGGE method as a non-cultivation method was found to be a powerful tool for analysis of the microbial community, because the cultivation method could detect only a fraction of the microbial species present in these systems. The genetic diversity of the isolated bacteria belonging to the γ-Proteobacteria which reduced both nitrate and nitrite in the anaerobic packed bed was higher than that of the bacteria in the anaerobic fluidized bed. This suggested that a genetically diverse microbial community stabilized the denitrifying performance in the anaerobic packed bed.

    DOI

  • Metabolic behavior of denitrifying phosphate-accumulating organisms under nitrate and nitrite electron acceptor conditions

    Johwan Ahn, Tomotaka Daidou, Satoshi Tsuneda, Akira Hirata

    Journal of Bioscience and Bioengineering   92 ( 5 ) 442 - 446  2001年

     概要を見る

    The effects of various types of electron acceptors on anoxic phosphorus uptake were investigated in detail to obtain a better insight into the metabolic behavior of denitrifying phosphate-accumulating organisms. Batch experimental tests under three different electron acceptor conditions, i.e., nitrate, nitrite and mixtures of nitrate and nitrite, were carried out using activated sludge cultivated in a sequencing batch reactor. The experimental results confirmed no inhibition of the utilization of nitrate or nitrite as an electron acceptor for anoxic phosphorus uptake. Anoxic phosphorus uptake occurred provided there was an electron acceptor present regardless of whether it was nitrate or nitrite. However, for nitrite a relatively small amount of anoxic phosphorus was taken up per nitrogen denitrified compared to nitrate. On the other hand, the amount of anoxic phosphorus taken up per nitrogen denitrified increased with an increase in the initial loading amount of electron acceptor in the case of nitrate, whereas it slightly decreased nitrite. Moreover, the amount of phosphorus taken up per nitrogen denitrified decreased with increasing mixed liquor suspended solid (MLSS) concentration in the case of nitrate, while it slightly increased for nitrite. From these results, it was confirmed that the activity of anoxic phosphorus uptake is strongly associated with the type and the initial loading amount of electron acceptor and the MLSS concentration under anoxic conditions.

    DOI

  • Simultaneous Nitrogen and Phosphorus Removal from Nutrient-Rich Wastewater -I. Characterization of Denitrifying Phosphate-Accumulating Organisms-

    S. Tsuneda, J. Ahn, T. Daidou, A. Hirata

    Ann. Report Interdiscipl. Res. Inst. Environ. Sci.   19   67 - 75  2000年12月

  • 感光剤製造工程廃液の生物処理

    平田彰, 島本敦史, 飯田宏幸, 常田聡

    用水と廃水   42 ( 9 ) 775 - 780  2000年09月

  • Evaluation of Kinetic Parameters of Biochemical Reaction in Three-Phase Fluidized Bed Biofilm Reactor for Wastewater Treatment

    A. Hirata, T. Takemoto, K. Ogawa, J. Auresenia, S. Tsuneda

    Biochem. Eng. J.   5 ( 2 ) 165 - 171  2000年04月

  • Formation and Characteristics of Nitrifying Biofilm on a Membrane Modified with Positively-Charged Polymer Chains

    K. Hibiya, S. Tsuneda, A. Hirata

    Colloids and Surf. B: Biointerfaces   18 ( 2 ) 105 - 112  2000年03月

  • Effects of oxygen supply condition and specific biofilm interfacial area on phenol removal rate in a three-phase fluidized bed bioreactor

    A Hirata, AA Meutia, M Osawa, M Arai, S Tsuneda

    CANADIAN JOURNAL OF CHEMICAL ENGINEERING   78 ( 1 ) 95 - 101  2000年02月  [査読有り]

     概要を見る

    The effects of oxygen supply conditions and specific biofilm interfacial area on the phenol removal rate in a three-phase fluidized bed bioreactor were evaluated. the experimental data were well-explained by the semi-theoretical equation based on the assumption that the reaction rate follows first-order reaction kinetics with respect to oxygen and zero-order one with respect to phenol. Two cases; biological reaction as rate-controlling step and oxygen absorption as rate-controlling step, were both explicable by this semi-theoretical equation. The maximum volumetric phenol removal rate was 27.4 kg.m(-3) d(-1).

  • Rapid quantification and in situ detection of nitrifying bacteria in biofilms by monoclonal antibody method

    N Noda, H Ikuta, Y Ebie, A Hirata, S Tsuneda, M Matsumura, T Sumino, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   41 ( 4-5 ) 301 - 308  2000年  [査読有り]

     概要を見る

    Fluorescent antibody technique by the monoclonal antibody method is very useful and helpful for the rapid quantification and in situ detection of the specific bacteria like nitrifiers in a mixed baxterial habitat such as a biofilm. In this study, twelve monoclonal antibodies against Nitrosomonas europaea (IFO14298) and sixteen against Nitrobacter winogradskyi (IFO 14297) were raised from splenocytes of mice (BALB/c). It was found that these antibodies exhibited little cross reactivity against various kinds of heterotrophic bacteria. The direct cell count method using monoclonal antibodies could exactly detect and rapidly quantify N. europaea and N. winogradskyi. Moreover, the distribution of N. europaea and N. winogradskyi in a biofilm could be examined by in situ fluorescent antibody technique. It was shown that most of N. whogradskyi existed near the surface part and most of N. europaea existed at the inner part of the polyethylene glycol (PEG) gel pellet, which had entrapped activated sludge and used in a landfill leachate treatment reactor. it was suggested that this monoclonal antibody method was utilized for estimating and controlling the population of nitrifying bacteria as a quick and favorable tool.

  • The rapid quantification and detection of nitrifying bacteria by using monoclonal antibody method

    H Ikuta, N Noda, Y Ebie, A Hirata, S Tsuneda, M Matsumura, Y Inamori

    WATER SCIENCE AND TECHNOLOGY   42 ( 3-4 ) 1 - 7  2000年  [査読有り]

     概要を見る

    Monoclonal antibodies against the two kinds of nitrifying bacteria Nitrosomonas europaea (IFO14298) and Nitrobacter winogradskyi (IFO14297) were raised and isotypes of these monoclonal antibodies, IgM and IgG(1), were successfully obtained. Cross reactivities of these monoclonal antibodies against various kinds of representative heterotrophic bacteria turned out to be relatively low by competitive ELISA. In contrast, these monoclonal antibodies were very specific for nitrifying bacteria used as antigens. By means of sandwich ELISA using different isotype monoclonal antibodies such as IgM and IgG(1), calibration curves were successfully developed for quantification of nitrifying bacteria. It was shown that the obtainable lower limit of quantification of N. europaea and N. winogradskyi were 7.0 x 10(6) N/ml and were 6.0 x 10(5) N/ml, respectively. Nitrifying bacteria in activated sludge of advanced domestic wastewater treatment johkaso were counted by sandwich ELISA and MPN methods. The bacterial number estimated by MPN method was lower than that estimated by sandwich ELISA, It was indicated that this monoclonal antibody method could be used asa quick and powerful tool for estimating and controlling the population of nitrifying bacteria in the advanced domestic wastewater treatment processes.

  • Tailoring of highly efficient nitrifying biofilms in fluidized bed for ammonia-rich industrial wastewater treatment

    S Tsuneda, T Miyoshi, Y Aoi, A Hirata

    WATER SCIENCE AND TECHNOLOGY   42 ( 3-4 ) 357 - 362  2000年  [査読有り]

     概要を見る

    We proposed two tailoring methods for efficient nitrifying biofilms on particles which are expected to be used in fluidized bed in nitrogen removal processes for industrial wastewaters. The first method was examined with gradual reduction of the hydraulic retention time in continuous feeding reactor to form biofilm with high nitrification ability. As a result, nitrification rate was successfully improved mainly due to acclimation of nitrifying bacteria to higher loading. The second tailoring method for nitrifying biofilm started with the biofilm which had been previously constructed in synthetic domestic wastewater containing high concentration of NH4+-N as well as various biodegradable organic compounds. Stepwise reduction of CIN ratio in inlet wastewater was performed during one month simultaneously with observation of microbial population dynamics in the biofilm using fluorescent in situ hybridization (FISH) analysis. As a result, this acclimation process promoted occupation of the biofilm by ammonia-oxidizing bacteria and resulted in making suitable biofilm structure for nitrification of ammonia-rich industrial wastewater. Moreover, it is confirmed that this new tailoring method greatly shortened required time to obtain nitrifying biofilms.

  • Microbial ecology of nitrifying bacteria in wastewater treatment process examined by fluorescence in situ hybridization

    Yoshiteru Aoi, Tomoko Miyoshi, Toshiyuki Okamoto, Satoshi Tsuneda, Akira Hirata, Atsushi Kitayama, Teruyuki Nagamune

    Journal of Bioscience and Bioengineering   90 ( 3 ) 234 - 240  2000年

     概要を見る

    The microbial ecology of nitrifying bacteria in various types of wastewater treatment processes and the dynamic response of the microbial ecology in biofilms were investigated using fluorescence in situ hybridization (FISH) with 16S rRNA-targeted oligonucleotide probes. Nitrifying bacteria were found to exhibit various organizational forms under different conditions of substrate composition and concentration. Ammonia-oxidizing bacteria were dominant in ammonia-rich inorganic wastewater, while heterotrophic bacteria and ammonia-oxidizing bacteria were localized at different positions in the biofilm in organic wastewater. The dynamics of the microbial ecology in the biofilm with regard to the spatial distribution of ammonia-oxidizing bacteria and heterotrophic bacteria caused by a gradual change in substrate composition was successfully monitored by FISH analysis.

    DOI

  • 写真廃液中の難分解性有機物の微生物分解

    平田彰, 山下秀人, 常田聡

    用水と廃水   41 ( 9 ) 808 - 812  1999年09月

  • 紫外線照射と過酸化水素逐次添加を併用したジクロロメタンの高速分解処理

    平田彰, 石井純, 常田聡

    水環境学会誌   22 ( 5 ) 396 - 402  1999年05月

  • Radiation-induced graft polymerization is the key to develop high-performance functional materials for protein purification

    K Saito, S Tsuneda, M Kim, N Kubota, K Sugita, T Sugo

    RADIATION PHYSICS AND CHEMISTRY   54 ( 5 ) 517 - 525  1999年05月  [査読有り]

     概要を見る

    We have described a preparation scheme for immobilizing polymer chains at a uniformly high density onto a microfiltration membrane. Highly efficient protein recovery was demonstrated by the results of the determination of breakthrough and elution curves. The three requirements of high rare, high capacity, and repeated use for the protein recovery were satisfied by ensuring the occurrence of convection, multilayer binding, and hydrophilization, respectively. In addition, easy scale-up to fabrication of a membrane module was verified on a small scale. (C) 1999 Published by Elsevier Science Ltd, All rights reserved.

  • 写真廃液の再生とゼロエミッション化

    平田彰, 武井浩樹, 常田聡

    化学工業   50 ( 2 ) 113 - 118  1999年02月

  • Tailoring of a smooth polycrystalline gold surface as a suitable anchoring site for a self-assembled monolayer

    S Tsuneda, T Ishida, N Nishida, M Hara, H Sasabe, W Knoll

    THIN SOLID FILMS   339 ( 1-2 ) 142 - 147  1999年02月  [査読有り]

     概要を見る

    We investigated an effective pretreatment method for a polycrystalline gold film surface on which an ordered self-assembled monolayer (SAM) could form. The wetting properties of the SAM surface determined by the hysteresis between advancing and receding contact angles against water and hexadecane revealed that the ordered SAM was formed on the gold surface pretreated with a combination of UV/ozone exposure and ethanol rinsing prior to SAM formation. The change in optical properties of the gold film surface was observed by surface plasmon spectroscopy (SPS), indicating that pure ethanol rinsing makes the gold surface smooth by removing small gold grains oxidized by UV/ozone exposure. (C) 1999 Elsevier Science S.A. All rights reserved.

  • High resolution x-ray photoelectron spectroscopy measurements of octadecanethiol self-assembled monolayers on Au(111)

    T Ishida, M Hara, Kojima, I, S Tsuneda, N Nishida, H Sasabe, W Knoll

    LANGMUIR   14 ( 8 ) 2092 - 2096  1998年04月  [査読有り]

     概要を見る

    We have measured high-resolution X-ray photoelectron spectroscopy (XPS) spectra of 1-octadecanethiol (ODT) self-assembled monolayers (SAMs) on a Au(111) surface in order to investigate the Au-S binding properties at the initial stage of SAM growth and after the desorption of the ODT from the Au surface. For the SAM prepared by the 1 min immersion into the ODT solution, we found new sulfur species around 161 eV and assigned it to isolated sulfur without C-S cleavage. We also confirmed the presence of a similar 161 eV peak in the S(2p) spectra after desorption of the ODT molecules. Furthermore, we observed a peak shift in the carbon 1s (C(1s)) peak, depending on the surface coverage of the ODT. In addition to the C(1s) peak of 285.1 eV which might correspond to alkyl chains of densely packed ODT molecules, another lower binding energy peak at 284.3 eV appeared after annealing. This lower C(1s) binding energy peak formation suggested that some of the alkyl chains for the remaining ODT molecules might be oriented parallel to the Au surface after annealing.

  • 嫌気好気生物膜法による産業廃水の高度処理

    平田彰, 常田聡

    ケミカルエンジニヤリング   43 ( 3 ) 188 - 192  1998年03月

  • Fluorescence study on the conformational change of an amino group-containing polymer chain grafted onto a polyethylene microfiltration membrane

    S Tsuneda, T Endo, K Saito, K Sugita, K Horie, T Yamashita, T Sugo

    MACROMOLECULES   31 ( 2 ) 366 - 370  1998年01月  [査読有り]

     概要を見る

    The fluorescence probe technique was used to investigate the characteristics of an amino group-containing polymer chain grafted onto a polyethylene microfiltration (MF) membrane. The amino group-containing polymer chain labeled with a dansyl group that served as a fluorescence probe was grafted onto a polyethylene MF membrane by radiation-induced graft polymerization. The conformational changes of the grafted polymer chain (graft chain) in various solvents were monitored by considering that the steady-state fluorescence emission spectrum of the dansyl group was affected by the polarity of the solvent, the polyethylene, and the graft chain itself. The shift of the emission peak wavelength of graft chains with different lengths demonstrated that the graft chain containing amino groups stretched in water and methanol and shrank in dimethylformamide, acetone, and benzene. These results corresponded to changes in solvent permeability through the membrane pore to which the amino group-containing polymer chains were grafted.

  • Kinetics of biological treatment of phenolic wastewater in three-phase fluidized bed containing biofilm and suspended sludge

    A Hirata, M Noguchi, N Takeuchi, S Tsuneda

    WATER SCIENCE AND TECHNOLOGY   38 ( 8-9 ) 205 - 212  1998年  [査読有り]

     概要を見る

    Phenolic wastewater was treated in complete mixing type three-phase fluidized bed which contained both biofilm and suspended sludge. By considering the contributions of biofilm and suspended sludge to biodegradation of phenol separately, phenol removal rates with biofilm and with suspended sludge were evaluated both theoretically and experimentally. As a result, biodegradation of phenolic wastewater by biofilm process could be treated as a zero-order reaction. The volumetric biological removal rates with biofilm was proportional to the specific surface area of the biofilm with biodegradation coefficients (K) of 1.25x10(-2) kg-PhOH/m(2)-biofilm/d At a lower suspended sludge concentration, bioparticle diameter and bioparticle holdup in the three-phase fluidized bed reactor were decisive factors for the efficiency of phenol treatment, and it was also proved that almost 100 % of phenol removal could be attained at a larger specific biofilm surface area per volumetric phenol loading rate than 80 m(2)/(kg-PhOH/d) without suspended sludge. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.

  • Surface-conditioning effect of gold substrates on octadecanethiol self-assembled monolayer growth

    T Ishida, S Tsuneda, N Nishida, M Hara, H Sasabe, W Knoll

    LANGMUIR   13 ( 17 ) 4638 - 4643  1997年08月  [査読有り]

     概要を見る

    The surface-conditioning effect of gold substrates on n-octadecanethiol (ODT) self-assembled monolayer (SAM) growth was studied by X-ray photoelectron spectroscopy (XPS). The gold substrates were immersed in an ethanol solution containing 1 mM ODT for 1 h. The C/Au ratios of the ODT SAMs estimated by XPS formed on gold substrates depended on the amount of contamination on the gold surface. A full-coverage ODT SAM was successfully obtained on the gold substrate after ultraviolet light (UV)/ozone treatment for 1 h and rinsing with pure ethanol for 1 h. XPS measurements indicated that low contamination levels and a sulfur-free gold surface were obtained using this pretreatment and, hence, the adsorption of ODT molecules on gold proceeded efficiently. On the other hand, the C/Au ratio of an ODT SAM on a contaminated gold substrate was less following immersion in an ODT solution for 1 h, because surface contamination may reduce the adsorption rate of ODT molecules on the gold surface. When the gold substrate was rinsed with a chloroform solution for 1 h before SAM formation, the lowest C/Au ratio was obtained. XPS results showed that sulfur atoms quickly adsorbed onto the gold surface after chloroform rinsing and prevented the adsorption of ODT molecules onto the gold surface.

  • Local mobility of polymer chain grafted onto polyethylene monitored by fluorescence depolarization

    S Tsuneda, T Endo, K Saito, K Sugita, K Horie, T Yamashita, T Sugo

    CHEMICAL PHYSICS LETTERS   275 ( 3-4 ) 203 - 210  1997年08月  [査読有り]

     概要を見る

    The fluorescence depolarization method was used for investigating the local mobility of polymer chains grafted onto a porous polyethylene membrane. The real value of the rotational diffusion coefficient of a dansyl probe attached to the grafted polymer chain was obtained by using a correction method which eliminated the effect of multiple scattering on fluorescence anisotropy, The rotational mobility of the dansyl probe attached to the grafted polymer chain was sensitive to both degree of grafting and solvent polarity, which indicated that the conformation of the grafted polymer chain and the pore size of the base membrane strongly governed the dynamic parameters of the grafted polymer chain. (C) 1997 Elsevier Science B.V.

  • Treatment of photographic processing wastewater using anaerobic-aerobic biofilm reactor

    A Hirata, HS Lee, S Tsuneda, T Takai

    WATER SCIENCE AND TECHNOLOGY   36 ( 12 ) 91 - 99  1997年  [査読有り]

     概要を見る

    Two types of anaerobic-aerobic biofilm processes were applied to the treatment of the photographic processing wastewater. Two-phase fixed bed reactor packed with sponge cubic media and completely mixing three-phase fluidized bed reactor, respectively, were used as an anaerobic and aerobic biofilm reactors. One of the aerobic biofilm reactors was packed with cement balls (CB) made by crushed cement particles, and another packed with biological activated carbon (BAC). The fivefold diluted photographic processing wastewater, from which Ag had been removed previously, was used as an influent (BOD 5,700 g/m(3), CODcr 17,000 g/m(3), T-N 2,600 g/m(3)). During long-term continuous biological treatment, BOD values in effluent decreased gradually and reached 280 g/m(3), which could fulfill the sewage discharge control value in Japan (BOD &lt; 600 g/m(3)). It took more than one year to acclimatize the sludge and to get the effective microorganisms for degrading the compounds in the photographic processing wastewater. However, pH values in the aerobic biofilm reactors fell down to 3 similar to 4. This was possibly because thiosulfate (5,700 g/m(3)) in the photographic processing wastewater was almost oxidized to sulfate by sulfur-oxidizing bacteria. For the purpose of obtaining higher BOD removal efficiency, pH in the aerobic biofilm reactor was adjusted to 7 using pH controller. As a result, BOD removal ratio was gradually improved, and the sewage discharge control value was steadily achieved after 181 days. The number of bacteria in the anaerobic biofilm reactor and the aerobic biofilm reactor with pH controller were 6.0 x 10(9) N/mL and 1.1 x 10(8) N/mL, respectively. (C) 1997 IAWQ. Published by Elsevier Science Ltd.

  • Alkyl chain length effect on growth kinetics of n-alkanethiol self-assembled monolayers on gold studied by X-ray photoelectron spectroscopy

    T Ishida, N Nishida, S Tsuneda, M Hara, H Sasabe, W Knoll

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS   35 ( 12B ) L1710 - L1713  1996年12月  [査読有り]

     概要を見る

    Growth kinetics of self-assembled monolayers (SAMs) of n-alkanethiols on gold substrates was studied by X-ray photoelectron spectroscopy (XPS). We compared adsorption kinetics for three alkanethiol homologues: butanethiol (C4SH), dodecanethiol (C12SH), and octadecanethiol (C18SH). Results of-quantitative analysis by XPS suggested that the adsorption rate of short alkyl chain thiols is higher than that of long ones on gold substrates at the initial growth stage, in contrast to previous reports. For C4SH SAM formation, we have also confirmed the occurrence of a replacement effect from contamination to SAM on gold, based on our observation of a decrease in the amount of carbon and an increase in the amount of gold where as determined from XPS spectra.

  • Ring-opening reaction of poly-GMA chain grafted onto a porous membrane

    M Kim, S Kiyohara, S Konishi, S Tsuneda, K Saito, T Sugo

    JOURNAL OF MEMBRANE SCIENCE   117 ( 1-2 ) 33 - 38  1996年08月  [査読有り]

     概要を見る

    An epoxy-group-containing polymer chain was grafted onto a porous polyethylene membrane of hollow-fiber form by applying radiation-induced graft polymerization, The produced epoxide was converted into a diol group, ion-exchange (diethylamino and sulfonic acid) and chelate-forming (ethylenediamine and iminodiacetic acid) groups, and pseudoaffinity ligands (phenylalanine and tryptophan), The conversion of the epoxide into the functional group was investigated as a function of the degree of GMA grafting and molecular weight of the reactants. A reactant with low molecular weight exhibited a high conversion. The high conversion of the epoxide into the ion-exchange group caused the extension of the polymer chain grafted onto the pore interface and decreased the water permeability through the hollow-fiber membrane.

  • HYDRODYNAMIC EVALUATION OF 3-DIMENSIONAL ADSORPTION OF PROTEIN TO A POLYMER-CHAIN GRAFTED ONTO A POROUS SUBSTRATE

    S TSUNEDA, H KAGAWA, K SAITO, T SUGO

    JOURNAL OF COLLOID AND INTERFACE SCIENCE   176 ( 1 ) 95 - 100  1995年12月  [査読有り]

     概要を見る

    A porous hollow-fiber membrane was modified with diethylamino (DEA) and ethanolamino (EA) groups by radiation-induced graft polymerization and subsequent chemical modifications. Adsorption behavior of bovine serum albumin (BSA) was investigated by permeating a BSA buffer solution through the membrane. A polymer chain grafted onto the pore surface of the membrane held BSA in multilayers, i.e., three-dimensionally in a tentacle-like manner. The membrane with a DEA group density of 2.5 mol/kg had a binding capacity for BSA of 443 g/kg, equivalent to 11 times the monolayer adsorption. Permeation of a buffer solution containing 0.5 M NaCl as an eluent caused the graft chain to shrink, resulting in restricted diffusion of BSA departing from the graft chain toward the pore interior while realizing a quantitative elution. Hydrodynamic analysis of the change in permeation pressure accompanying BSA binding to the graft chain showed that the BSA molecules layered in the graft chains form a closely packed structure. (C) 1995 Academic Press, Inc.

  • NOVEL ION-EXCHANGE MEMBRANES FOR ELECTRODIALYSIS PREPARED BY RADIATION-INDUCED GRAFT-POLYMERIZATION

    S TSUNEDA, K SAITO, H MITSUHARA, T SUGO

    JOURNAL OF THE ELECTROCHEMICAL SOCIETY   142 ( 11 ) 3659 - 3663  1995年11月  [査読有り]

     概要を見る

    Novel ion-exchange membranes containing sulfonic acid (SO3H) and trimethyl ammonium [N(CH3)(3)] groups were prepared by a simple method of radiation-induced cografting of sodium styrenesulfonate (SSS) with acrylic acid (AAc) and vinyl benzyl trimethyl ammonium chloride (VBTAC) with 2-hydroxyethyl methacrylate (HEMA), onto a polyethylene film with a thickness of 50 mu m. The high density graft chain was introduced throughout the polyethylene film. The maximum cation- and anion-exchange capacities of the resultant membranes were 2.5 and 1.3 mol/kg, respectively. These membranes exhibited an electrical resistance one order lower than commercially available ion-exchange membranes; for example, 12 h cografting provided cation- and anion-exchange membranes whose electrical resistances in a 0.5 M NaCl solution were 0.25 and 0.85 Omega cm(2) respectively. From the evaluation of electrodialytic desalination in a batch mode, using a pair of the graft-type ion-exchange membranes, the time required to achieve 99.5% desalination of the initial 0.5 M NaCl solution was reduced to 85% comparing with that of the commercial ion-exchange membranes.

  • PROTEIN ADSORPTION CHARACTERISTICS OF POROUS AND TENTACLE ANION-EXCHANGE MEMBRANE PREPARED BY RADIATION-INDUCED GRAFT-POLYMERIZATION

    S TSUNEDA, K SAITO, T SUGO, K MAKUUCHI

    RADIATION PHYSICS AND CHEMISTRY   46 ( 2 ) 239 - 245  1995年08月  [査読有り]

     概要を見る

    A polymer chain containing a diethylamino group was grafted onto the pore surface of a porous hollow-fiber membrane by radiation-induced graft polymerization. Dependence of the protein binding capacity of the membrane on environmental parameters such as salt concentration, pH and temperature was investigated. Saturation capacity of protein bound onto the graft chain containing ion-exchange group was governed by the conformation of the graft chain and the intensity of ion-exchange interaction. The conformation of the graft chain was investigated based on the pore radius of the membrane estimated from the permeation flux of a buffer solution through the membrane. By sufficiently permeating a bovine serum albumin (BSA) solution within the concentration range of 0.2-10 mg-BSA/ml through the membrane, the BSA binding capacity was determined. With increasing salt concentration or pH of the protein buffer solution, the graft chain shrank and BSA binding capacity decreased. On the other hand, the BSA binding capacity slightly increased with increasing temperature, and the conformation of the graft chain was insensitive to temperature in the range from 278 to 303 K. The bound BSA could be quantitatively eluted by permeating a buffer solution containing 0.5 M NaCl, and no deterioration in the BSA binding capacity was observed during five cycles of adsorption, elution and conditioning.

  • HIGHLY EFFICIENT ENZYME RECOVERY USING A POROUS MEMBRANE WITH IMMOBILIZED TENTACLE POLYMER-CHAINS

    S MATOBA, S TSUNEDA, K SAITO, T SUGO

    BIO-TECHNOLOGY   13 ( 8 ) 795 - 797  1995年08月  [査読有り]

     概要を見る

    We describe a novel ''tentacle-type'' porous membrane that allows adsorption of enzymes in multilayers in amounts about 50-fold those permitted by monolayer adsorption. A diethylamino (DEA) group as an anion-exchanger was appended to a polymer chain, grafted onto the pores of a hollow-fiber membrane. A urease solution was forced to permeate through the pores of the anion-exchange membrane, which had a DEA group density up to 2.9 mmol per gram of membrane and a thickness of 0.8 mm. The grafted chain with a higher DEA group density provided a larger number of three-dimensional adsorption (tentacle-like binding) sites for urease. The binding capacity exceeded one gram of urease per gram of the membrane at DEA group densities higher than 1.6 mmol per gram, which amounted to a more than 37-fold greater amount of adsorbed enzyme compared to monolayer adsorption. In addition, urease captured by the DEA on the graft chain could be quantitatively eluted with retention of 90% of the feed urease activity.

  • Protein adsorption characteristics of porous and tentacle anion-exchange membrane prepared by radiation-induced graft polymerization

    Satoshi Tsuneda, Kyoichi Saito, Takanobu Sugo, Keizo Makuuchi

    Radiation Physics and Chemistry   46 ( 2 ) 239 - 245  1995年  [査読有り]

     概要を見る

    A polymer chain containing a diethylamino group was grafted onto the pore surface of a porous hollow-fiber membrane by radiation-induced graft polymerization. Dependence of the protein binding capacity of the membrane on environmental parameters such as salt concentration, pH and temperature was investigated. Saturation capacity of protein bound onto the graft chain containing ion-exchange group was governed by the conformation of the graft chain and the intensity of ion-exchange interaction. The conformation of the graft chain was investigated based on the pore radius of the membrane estimated from the permeation flux of a buffer solution through the membrane. By sufficiently permeating a bovine serum albumin (BSA) solution within the concentration range of 0.2-10 mg-BSA/ml through the membrane, the BSA binding capacity was determined. With increasing salt concentration or pH of the protein buffer solution, the graft chain shrank and BSA binding capacity decreased. On the other hand, the BSA binding capacity slightly increased with increasing temperature, and the conformation of the graft chain was insensitive to temperature in the range from 278 to 303 K. The bound BSA could be quantitatively eluted by permeating a buffer solution containing 0.5 M NaCl, and no deterioration in the BSA binding capacity was observed during five cycles of adsorption, elution and conditioning. © 1995.

    DOI

  • HIGH-THROUGHPUT PROCESSING OF PROTEINS USING A POROUS AND TENTACLE ANION-EXCHANGE MEMBRANE

    S TSUNEDA, K SAITO, S FURUSAKI, T SUGO

    JOURNAL OF CHROMATOGRAPHY A   689 ( 2 ) 211 - 218  1995年01月  [査読有り]

     概要を見る

    The immobilization of polymer chains containing a diethylamino (DEA) group on the pore surface of a porous hollow-fibre membrane is reported. This novel membrane can collect proteins at a high rate and high capacity because of convective transport and multi-layering of proteins. Overlapping of the breakthrough curves for different residence times of bovine serum albumin (BSA) solution demonstrates that the diffusional resistance of BSA to the DEA group anchored to the polymer chain was negligible. Membranes with a higher density of DEA groups exhibited a higher binding capacity for BSA. For example, a membrane with a DEA group density of 2.9 mol/kg had a BSA binding capacity of 490 g/kg, which was equivalent to eleven times the adsorption capacity of a monolayer. This vertical layering is due to holding of the BSA molecules in a tentacle-like manner by the graft chains extending from the pore surface towards the pore interior.

  • SULFONIC-ACID CATALYSTS PREPARED BY RADIATION-INDUCED GRAFT-POLYMERIZATION

    T MIZOTA, S TSUNEDA, K SAITO, T SUGO

    JOURNAL OF CATALYSIS   149 ( 1 ) 243 - 245  1994年09月  [査読有り]

  • HYDROLYSIS OF METHYL ACETATE AND SUCROSE IN SO3H-GROUP-CONTAINING GRAFTED POLYMER-CHAINS PREPARED BY RADIATION-INDUCED GRAFT-POLYMERIZATION

    T MIZOTA, S TSUNEDA, K SAITO, T SUGO

    INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH   33 ( 9 ) 2215 - 2219  1994年09月  [査読有り]

     概要を見る

    The sulfonic acid (SO3H) group was attached to polyethylene by radiation-induced graft polymerization of sodium p-styrenesulfonate and compared with the SO3H group introduced into the polystyrene chain cross-linked with divinylbenzene. The catalytic activities of the SO3H group were measured in a batch mode for the hydrolysis of methyl acetate and sucrose. The temperature dependence of the reaction rate constants for the hydrolysis was determined. For the hydrolysis of methyl acetate, the SO3H group anchored to the grafted polymer chain had the same activity as the SO3H group introduced into the cross-linked polymer chain. On the other hand, the graft-type acid catalyst had about 10 times the hydrolytic activity for sucrose as the cross-linked acid catalyst.

  • RADIATION-INDUCED CRAFT POLYMERIZATION OF VINYL BENZYLTRIMETHYLAMMONIUM CHLORIDE ONTO POLYETHYLENE FILM

    YC NHO, T SUGO, S TSUNEDA, K MAKUUCHI

    JOURNAL OF APPLIED POLYMER SCIENCE   51 ( 7 ) 1269 - 1275  1994年02月  [査読有り]

     概要を見る

    An attempt was made to introduce a strong base anion-exchange group by radiation-induced grafting of vinyl benzyltrimethylammonium chloride (VBTAC) onto polyethylene film. Both two-step grafting and comonomer grafting techniques were tried owing to the difficulty of direct graft polymerization of VBTAC onto polyethylene. 2-Hydroxyethyl methacrylate (HEMA) and ethyl methacrylate (EMA), having the same backbone structure except that the hydroxyl group of HEMA was grafted onto the polyethylene film and then VBTAC was grafted to examine the reactivity of VBTAC with each grafted polyethylene film. Cografting of the binary mixtures of VBTAC and HEMA, or EMA, onto polyethylene film was also carried out. (C) 1994 John Wiley & Sons, Inc.

  • BINDING OF LYSOZYME ONTO A CATION-EXCHANGE MICROPOROUS MEMBRANE CONTAINING TENTACLE-TYPE GRAFTED POLYMER BRANCHES

    S TSUNEDA, H SHINANO, K SAITO, S FURUSAKI, T SUGO

    BIOTECHNOLOGY PROGRESS   10 ( 1 ) 76 - 81  1994年01月  [査読有り]

     概要を見る

    Ion-exchange adsorption of lysozyme to the sulfonic acid (SO3H) group on polymer chains grafted onto microporous polyethylene hollow-fiber membranes was examined. The lysozyme solution was forced to permeate across the hollow fiber. Diversely anchored SO3H groups, i.e., SP and SS groups, were introduced into the membrane by reaction of the glycidyl methacrylate-grafted membrane with propanesultone and sodium sulfite, respectively. The resulting SP and SS group-containing membranes, designated as SP-T and SS-T fibers, respectively, had 95 and 77 % water flux of the original membrane, respectively. The binding capacity of lysozyme as a function of the SO3H group density was compared between the SP-T and SS-T fibers from measurement of the ion-exchange breakthrough curves during the permeation of lysozyme solution across the SP-T and SS-T fibers. The binding capacity of lysozyme to the SP-T fiber remained constant, independent of the SP group density, whereas that to the SS-T fiber increased linearly with increasing SS group density. This difference was explained by means of a model whereby lysozyme adheres onto the SP group-containing grafted polymer branches, while the SS group-containing grafted polymer branches hold lysozyme in a tentacle-like manner.

  • ATTACHMENT OF SULFONIC-ACID GROUPS TO VARIOUS SHAPES OF POLYETHYLENE, POLYPROPYLENE AND POLYTETRAFLUOROETHYLENE BY RADIATION-INDUCED GRAFT-POLYMERIZATION

    S SUGIYAMA, S TSUNEDA, K SAITO, S FURUSAKI, T SUGO, K MAKUUCHI

    REACTIVE POLYMERS   21 ( 3 ) 187 - 191  1993年12月  [査読有り]

     概要を見る

    Sulfonic acid (SO3H) groups were attached to four different polymeric substrates by means of cografting sodium styrene sulfonate (SSS) with acrylic acid (AAc). The polymeric substrates were: microporous polyethylene (PE) hollow-fiber membrane, polypropylene (PP) tube, non-woven fabric made from PE and PP, and polytetrafluoroethylene (PTFE) film. The polymers were pre-irradiated by means of an electron beam source and immersed into monomer mixtures of SSS and AAc at 323 K. The molar ratio of the sulfonic acid groups to carboxyl (COOH) groups in the grafted polymers increased with reaction time. The salt-splitting capacities of the resultant ion exchangers, after 20 h of reaction, were 2.5, 1.4, 1.6 and 1.1 mol/kg for hollow fiber, tube, non-woven fabric and film, respectively. These values are in the range of salt-splitting capacities characteristic for conventional cation exchangers based on styrene-divinyl benzene copolymer beads.

  • SIMPLE INTRODUCTION OF SULFONIC-ACID GROUP ONTO POLYETHYLENE BY RADIATION-INDUCED COGRAFTING OF SODIUM STYRENE-SULFONATE WITH HYDROPHILIC MONOMERS

    S TSUNEDA, K SAITO, S FURUSAKI, T SUGO, K MAKUUCHI

    INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH   32 ( 7 ) 1464 - 1470  1993年07月  [査読有り]

     概要を見る

    The sulfonic acid (SO3H) group was readily introduced into a polyethylene (PE) membrane by radiation-induced cografting of sodium styrenesulfonate (SSS) with hydrophilic monomers such as acrylic acid (AAc) and hydroxyethyl methacrylate (HEMA). The density of SSS grafted onto the PE membrane was determined as a function of molar ratio of hydrophilic monomer to SSS in the monomer mixture. Immersion of the electron-beam-irradiated PE membrane into the mixture of SSS and HEMA for 5 h at 323 K provided the SO3H density of 2.5 mol/kg of the H-type product.

  • ION-EXCHANGE OF LYSOZYME DURING PERMEATION ACROSS A MICROPOROUS SULFOPROPYL-GROUP-CONTAINING HOLLOW FIBER

    H SHINANO, S TSUNEDA, K SAITO, S FURUSAKI, T SUGO

    BIOTECHNOLOGY PROGRESS   9 ( 2 ) 193 - 198  1993年03月  [査読有り]

     概要を見る

    A microporous hollow fiber containing a sulfopropyl (SP) group as a strongly acidic cation-exchange group was prepared by radiation-induced graft polymerization of glycidyl methacrylate, followed by hydrolysis of the resulting epoxide group into a diol, and then conversion of the diol into the SP group. The SP group density of the resulting hollow fiber ranged from 0.21 to 0.84 mol/kg of dry fiber with a pure water flux of 2.7 m/h at a filtration pressure of 0.1 MPa. Lysozyme adsorption was examined during permeation of the lysozyme solution (pH 6) through the pores across a microporous cation-exchange hollow fiber. The lysozyme concentration of the effluent penetrating the outside of the hollow fiber did not change irrespective of the residence time of the solution across the hollow fiber, which was indicative of the negligible diffusional resistance of lysozyme to the SP group. The binding capacity of lysozyme to the fiber was constant in this range of SP group density. For comparison, the adsorption characteristics of a cupric chloride solution during permeation were also determined. The binding capacity of Cu to the fiber increased linearly with increasing SP group density, because cupric ions of a smaller size than lysozyme can invade the depths of the grafted polymer branches formed in the amorphous domain of the polymer matrix.

  • PREPARATION OF MICROFILTRATION MEMBRANES CONTAINING ANION-EXCHANGE GROUPS

    K KOBAYASHI, S TSUNEDA, K SAITO, H YAMAGISHI, S FURUSAKI, T SUGO

    JOURNAL OF MEMBRANE SCIENCE   76 ( 2-3 ) 209 - 218  1993年02月  [査読有り]

     概要を見る

    Anion-exchange groups were introduced into an existing microfiltration membrane by radiation-induced grafting and subsequent chemical modification. The tertiary-amino-group-containing monomers, i.e. diethylaminoethyl methacrylate (DEAEMA) and vinyl pyridine (VP), and epoxy-group-containing monomer, i.e. glycidyl methacrylate (GMA), were grafted onto the porous polyethylene hollow-fiber membrane. The epoxy group produced in the GMA-grafted hollow fiber was converted into tertiary amino groups by reaction with diethylamine (DEA) and 4-aminopyridine (AP). Subsequently, the DEA- and AP-modified hollow fibers and the DEAEMA- and VP-grafted hollow fibers were all quaternized with benzyl chloride (BC). Measurements of pure water flux and ion-exchange capacity of the resulting membranes, which contained a strongly basic anion-exchange group, demonstrated that the quaternized membrane (DEA-BC-T fiber) originating from the DEA-modified membrane was the most suitable membrane for anion collection by permeation through its pores. The DEA-BC-T fiber had a pure water flux of 1.0 m/hr at a filtration pressure of 0.1 MPa and an ion-exchange capacity of 1 mol/kg.

  • Water/Acetone Permeability of Porous Hollow-Fiber Membrane Containing Diethylamino Groups on the Grafted Polymer Branches

    S. Tsuneda, K. Saito, S. Furusaki, T. Sugo, I. Ishigaki

    J. Membr. Sci.   71 ( 1-2 ) 1 - 12  1992年07月  [査読有り]

  • METAL COLLECTION USING CHELATING HOLLOW FIBER MEMBRANE

    S TSUNEDA, K SAITO, S FURUSAKI, T SUGO, J OKAMOTO

    JOURNAL OF MEMBRANE SCIENCE   58 ( 2 ) 221 - 234  1991年05月  [査読有り]

     概要を見る

    Three kinds of functional groups, iminodiacetate (IDA), amidoxime (AO), and phosphoric acid (PA), were introduced into a microfiltration hollow fiber membrane by radiation-induced grafting and subsequent chemical modification. The chelating hollow fibers containing AO or IDA groups exhibited a 1.1 m3/(m2-hr) pure water flux at 100% grafting of each precursor monomer, while the hollow fiber containing the PA group had a negligible flux. Breakthrough curves were obtained by permeating a metal-ion-containing feed solution radially from inside to outside of the chelating hollow fiber. The IDA chelating hollow fiber was superior to the AO chelating hollow fiber with regard to the collection of cobalt ion. The IDA hollow fiber, whose degree of glycidyl methacrylate grafting ranged from 20 to 260%, had a saturation capacity of cobalt ion of 0.13-1.3 mole Co per kg of base polymer.

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    古川和寛, 阿部洋, 伊藤嘉浩, 常田聡

    シーエムシー出版  2010年04月 ISBN: 9784781301839

  • リン資源の回収と有効利用

    蛯江美孝, 近藤貴志, 常田聡, 稲森悠平

    サイエンス&テクノロジー  2009年11月 ISBN: 9784903413761

  • マリンメタゲノムの有効利用

    野田 尚宏, 関口勇地, 松田 泰嘉, 谷 英典, 常田 聡

    シーエムシー出版  2009年07月 ISBN: 9784781301143

  • バイオフィルムの基礎と制御

    松本慎也, 常田聡

    株式会社エヌ・ティー・エス  2008年02月 ISBN: 9784860431501

  • 排水・汚水処理技術集成

    常田聡, 近藤貴志

    株式会社エヌ・ティー・エス  2007年05月

  • 一細胞定量解析の最前線 ライフサーベイヤ構築に向けて

    阿部洋, 古川和寛, 常田聡, 伊藤嘉浩

    シーエムシー出版  2006年12月

  • 複合微生物系の産業利用と新産業創出

    伊達康博, 青井議輝, 常田聡

    シーエムシー出版  2006年07月

  • Aerobic Granular Sludge, Water Environmental Management Series (WEMS)

    S. Tsuneda, Y. Ejiri, M. Ogiwara, T. Nagano, A. Hirata

    IWA Publishing  2005年04月

  • 最近の化学工学 54「バイオプロセスエンジニアリングの新展開-アップストリームからダウンストリームまで-」

    常田聡

    化学工業社  2002年11月

  • Advanced in Water and Wastewater Treatment Technology -Molecular Technology, Nutrient Removal, Sludge Reduction, and Environmental Health-

    Y. Aoi, T. Miyoshi, T. Okamoto, S. Tsuneda, A. Kitayama, E. Kayano, T. Nagamune, A. Hirata

    Elsevier  2000年09月

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Misc

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産業財産権

  • 骨髄増殖性腫瘍の診断

    山脇 紗耶, 常田 聡

    特許権

  • JAK2遺伝子の変異解析方法

    5787304

    常田 聡

    特許権

  • APOBEC3Gの活性測定方法

    常田 聡

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  • 微生物の単離培養方法及び培養キット

    5316983

    青井 議輝, 常田 聡

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  • 微生物の濃縮精製装置及び濃縮精製方法

    青井 議輝, 常田 聡

    特許権

  • 好気性グラニュールの形成方法、水処理方法及び水処理装置

    4925208

    常田 聡, 岸田 直裕

    特許権

  • インバースPCR方法に用いる鋳型DNA鎖の生産方法

    常田 聡, 寺原 猛

    特許権

  • 排水の処理方法および装置

    常田 聡, 平田 彰

    特許権

  • 排水処理装置

    4609989

    常田 聡, 平田 彰, 寺田 昭彦

    特許権

  • 廃水処理方法及び廃水処理装置

    常田 聡, 平田 彰

    特許権

  • 排水処理システム及び排水処理方法

    常田 聡, 平田 彰

    特許権

  • 硝化・脱窒同時進行型反応構造体及びその製造方法

    平田 彰, 青井 議輝, 常田 聡

    特許権

  • 窒素・リン同時除去型排水処理方法

    4267860

    常田 聡, 平田 彰

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  • 硝化グラニュールの形成方法

    常田 聡, 平田 彰

    特許権

  • メンブレンバイオリアクタによる窒素除去方法

    常田 聡, 平田 彰

    特許権

  • 担体を利用した高度処理方法および高度処理装置

    3716170

    平田 彰, 常田 聡, 小西 功三

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  • 生物膜の製造方法およびそれを用いた無機性アンモニア廃水連続処理装置

    常田 聡, 平田 彰

    特許権

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受賞

  • (公社)日本生物工学会・論文賞

    2018年06月  

  • (公財)長瀬科学技術振興財団会・長瀬研究振興賞

    2017年04月  

  • (公社)日本水環境学会・年間優秀論文賞

    2014年09月  

  • (公社)日本水環境学会・論文賞

    2013年06月  

  • (社)日本生物工学会・論文賞

    2011年09月  

  • (社)化学工学会・化学工学論文集優秀論文賞2006

    2007年09月  

  • (社)日本水環境学会・論文奨励賞

    2004年06月  

  • 日本水処理生物学会・論文賞

    2002年11月  

  • (社)日本生物工学会・論文賞

    2001年09月  

  • (社)化学工学会・奨励賞

    1995年03月  

▼全件表示

共同研究・競争的資金等の研究課題

  • トキシンーアンチトキシンシステムを攪乱する化合物の探索と機能評価

    研究期間:

    2019年04月
    -
    2022年03月
     

     概要を見る

    トキシン-アンチトキシンシステムは微生物の環境中での生存戦略を司るユニークなタンパク質である。中でもトキシンタンパク質であるMazFは通常の生育環境ではアンチトキシンタンパク質であるMazEと結合し活性が不活化されている。微生物が環境ストレスに曝されるとMazEが優先的に分解され、遊離したMazFがRNAを切断し、微生物を休眠状態に追い込んだり死に至らしめたりする。本研究では病原性微生物のMazFとMazEを取得し、それらの結合を撹乱することができる小分子化合物を探索する。さらに、得られた小分子化合物が病原性微生物の増殖に影響を及ぼす抗生物質としての機能を持つかどうかを評価する。本研究はトキシン-アンチトキシンシステムの一つであるMazEFに着目している。トキシンタンパク質であるMazFは細胞内で恒常的に発現している1本鎖RNAを配列特異的に切断する酵素であるが、通常の生育環境ではアンチトキシンタンパク質であるMazEと結合し、不活化されている。ある種のストレスに細胞が曝されるとトキシンに比べ不安定なMazEが優先的に分解され、遊離したMazFがRNAを切断し、細胞を休眠状態に追い込んだり死に至らしめたりする。本研究では、病原性微生物のMazFとMazEを取得し、それらの結合を撹乱することができる小分子化合物を蛍光スクリーニングアッセイにより探索することを目的としている。また、MazFのRNA切断活性を利用した微生物制御手法についても広く検討する。当該年度においては選定したモデル病原性微生物のMazFおよびMazEの取得を行い、目的とするMazFと同程度の分子量の候補タンパク質を得ることができた。この候補タンパク質についてRNAを特異的な認識配列で切断しているかどうかについて、複数種類の配列既知の人工長鎖RNAに対する切断活性試験や次世代シークエンサーを用いた認識配列の同定試験を行った。その結果、配列特異的に1本鎖RNAを切断するMazFであることが明らかとなった。さらにこのMazFに対するアンチトキシンであるMazEの取得も進めている。また、外来のMazFを病原性細菌に細胞外から導入して殺菌する手段についても検討した。今後の研究推進方策としては、蛍光核酸プローブを用いて、次世代シークエンサーで得られた認識配列について、その結果の妥当性を評価する。さらにMazEのアンチトキシン活性を評価するとともに、化合物ライブラリーのスクリーニングシステムの構築について準備を進める。さらに外来のMazFを利用した殺菌手段についても引き続き検討を進める。令和元年度においてはモデル病原性微生物のMazFおよびMazEの取得を試みた。モデル病原性微生物のトキシンタンパク質MazFとそのアンチトキシンタンパク質MazEについて配列情報をデータベースから取得し、アミノ酸配列情報等を確認・精査した。取得した配列情報に基づきタンパク質発現用のプラスミドの構築と宿主内での発現を行った。発現誘導の条件などを繰り返し精査することにより、目的とする分子量に近いタンパク質を取得することができた。さらに、取得したタンパク質のRNA切断活性を評価するために、特定の塩基配列をコードせず、また極端な偏りの配列を持たない人工的な配列から構成されるRNA鎖を複数種類用いた。具体的にはこれらのRNAを取得したタンパク質と一定時間反応させ、その際のRNAの切断様式を電気泳動により評価した。その結果、ランダムに切断したような切断パターンではなく、何らかの特定の認識配列箇所で切断したと考えられる切断パターンが得られた。これらの結果から取得したタンパク質がMazFであることが確信された。さらに、切断されたRNAの切断箇所にアダプター配列を付加した後に、次世代シークエンサーを用いて網羅的なRNA配列解析を行い、切断配列と思われる候補配列を複数見出すことに成功した。さらに、MazEの取得についても検討を進めた。一方、MazEFの結合を攪乱することに加え、細菌の必須遺伝子を切断する強力なMazFが得られた場合、これを他の病原性細菌に細胞外から導入し殺菌する、すなわち外来のMazFを利用した殺菌手段が考えられる。外来のMazFの病原性細菌への導入手法を検討した結果、MazF遺伝子を導入したファージを病原性細菌に感染させ、細胞内でMazFを発現させることを着想した。今年度は、ファージの遺伝子組換え方法について文献調査を行い、MazF搭載型ファージの作製プロトコルを確立した。今後の研究の推進方策としては、蛍光核酸プローブを用いた手法で認識配列のより精緻な評価を行う。蛍光核酸プローブはRNA配列が切断されれば発蛍光する仕組みであるため、RNA部分の配列を次世代シークエンサーで得た認識配列として、次世代シークエンサーで得られた結果の妥当性を評価する。複数の核酸プローブを準備して、これまでに得られた候補認識配列について一つ一つその妥当性を評価するとともに、認識配列に対して少しずつ塩基を置換した配列についてもその切断活性を評価し、認識配列を特定する。これまでのMazFの認識配列同定に関する研究成果を参考にすると、認識配列が一つであることの方が希であり、複数の認識配列を切断するものとして、認識配列決定に関する検討を進める。また、MazFに対するアンチトキシンであるMazEの取得も行い、MazFのRNA切断活性の抑制効果を評価する。MazEの抑制効果の評価にも蛍光核酸プローブを用いたアッセイシステムを用いる。MazFとMazEが取得でき、さらに認識配列の同定が終わった後に、蛍光核酸プローブを用いたMazEF複合体の結合を攪乱する化合物の探索を行う。最終的な目的とする病原性微生物のMazEF複合体の結合を攪乱する化合物の探索を効率的に行うことができるように、すでに認識配列が明らかとなっているMazFとそのアンチトキシンであるMazEを組み合わせて、化合物ライブラリーのスクリーニングシステムの構築について準備を進める。一方、外来のMazFを用いた病原性細菌の殺菌技術の開発においては、遺伝子組換え技術により、まず、目的のMazFをコードするファージミドベクターを構築する。つぎに、本ファージミドベクターを大腸菌に導入後、ヘルパーファージを感染させることで、病原性細菌に感染能を有するMazF搭載型ファージを作製する予定である

  • エネルギー蓄積型persisterの形成機構の解明および根絶技術の開発

    研究期間:

    2019年04月
    -
    2022年03月
     

     概要を見る

    一時的に休眠するpersisterが細菌集団のごく一部で形成されることによって感染症が完治しないことが問題視されている。我々は、乳酸代謝遺伝子ldhA発現を起因とするpersisterが、既往の経路とは異なり、エネルギー蓄積によって抗菌薬ストレスに備えていることを見出した。本研究では、これらの成果を発展させ、オミクス解析を用いてエネルギー蓄積型および従来のエネルギー枯渇型のpersister経路のメカニズムを比較解析する。それらの解析結果を基に、persisterの形成を阻害あるいは休眠状態から覚醒させることによって治療効果を高める代謝物質の同定を目指した基礎研究を行い、臨床応用を目指す。細菌集団の中には一部で表現型を変化させた休眠状態の細菌が存在しており、抗菌薬から生き残ることが知られている。生き残った個体(persister)は抗菌薬が除かれると覚醒し、増殖を開始するため、感染症の難治化および再燃を引き起こす。さらに、persisterは感染症患者内に長期間潜伏することによって耐性菌形成を促進させるため、persisterを効率よく根絶させることが重要な課題となっている。従来、persisterはエネルギー代謝が枯渇した状態にあることが一般的であるとされていたが、本研究室の先行研究により、乳酸デヒドロゲナーゼ遺伝子(ldhA)を過剰発現した大腸菌は、エネルギー代謝が増加することによって抗菌薬に対する抵抗性を高める新たなタイプのpersisterであることが示唆された。本研究ではエネルギー代謝を介したldhA発現によるpersister形成のメカニズムを明らかにすることを目的とした。そして、ldhA発現によるpersister形成阻害因子を探索することによって、persisterの根絶を目指した新たな感染症治療法を確立することを目指す。令和元年度は、大腸菌をモデル微生物として用い、ldhA発現による好気呼吸への影響を調べるため酸素消費率およびATP合成酵素発現量の測定を行った。その結果、ldhA過剰発現によってATPが増加した理由はATPの消費が抑制されたためであると考えられた。また、ldhA過剰発現株において、ATPを消費するpersister経路であるSOS応答の制御遺伝子recAの発現量が有意に増加することがわかった。このことから、ldhA発現により抗菌薬投与前にATPが蓄積されることによって、DNA損傷時にSOS応答を介したDNA修復が活発に起こり、抗菌薬投与下でも生存できることが示唆された。本研究では臨床的に意義のある細菌株を分譲機関や臨床施設から取り寄せることを考えていたが、令和元年度から学内での病原体の取扱いルールが変わったことや、海外の分譲機関から菌株を取り寄せるための手続きに予想以上の時間を要することが判明したため、使用菌株の変更が必要となり、実験のスタートが遅れてしまった。1)モデル微生物として大腸菌を用い、SOS応答制御遺伝子であるrecAの欠損株およびrecA欠損+ldhA過剰発現株、さらにldhA過剰発現株とコントロール株を用い、4株の抗菌薬処理後の生存率を比較する。この結果に基づいて、ldhAによるpersister形成とSOS応答の関係性を明らかにする。また、ldhA発現により、recAが活性化されるメカニズムを探索する。まずは、ldhA発現によりDNA損傷が引き起こされ、その結果recAが活性化するという仮説を立て、その可能性を検証する。2)臨床応用を踏まえ、尿路感染性大腸菌(UPEC)を用いて実験を進める。ATP濃度に応じて蛍光色が変化するタンパク質QUEENの遺伝子を導入したUPECをマイクロ流体デバイス内で培養し、1細胞ごとのATPレベルが経時的に測定できるようなシステムを構築する。このシステムを用いて抗菌薬抵抗性の高い細胞のATPレベルを評価する。また、QUEEN遺伝子を導入したUPECに対して様々なストレスを与え、蛍光強度の違いからfluorescence activated cell sorting (FACS) でATPレベルが高い細胞集団と低い細胞集団を分取する。それらの集団における各種遺伝子発現レベルおよび抗菌薬抵抗性を比較することで、エネルギー代謝を介したldhA発現によるpersister形成のメカニズムに迫る

  • 難治性感染症の原因となる休止細菌の分子機構解明

    研究期間:

    2015年04月
    -
    2017年03月
     

     概要を見る

    代謝活性を止めている休止細菌は,抗生物質存在下において生存できるため,感染症難治化の原因となる。本研究では,細菌の細胞骨格であるFtsZに着目し,細胞分裂時のZ-ringの形成を蛍光共鳴エネルギー移動で検出する遺伝子組換え大腸菌株の開発を行った。その結果,セルソーターを用いることで休止細菌と分裂細菌の分離に成功し,休止細菌は抗生物質(オフロキサシン)に対して高い抵抗性を持つことがわかった。また,トランスクリプトーム解析の結果,休止細菌は乳酸デヒドロゲナーゼの遺伝子発現を亢進させていることがわかった。さらに,マイクロ流体デバイスを用いたシングルセル観察によっても上記の結果が支持された

  • サンゴ礁生物からの新規抗ウイルス剤の探索

    研究期間:

    2014年04月
    -
    2017年03月
     

     概要を見る

    沖縄沿岸で採集したサンゴ礁生物からエキスライブラリー、ならびに少数の海洋天然物ライブラリーを作成し、それらを HCV NS3 helicase、HCV replicon、HBV core promoterなどの抗ウイルススクリーニングに提供した。ヒットしたエキスからは、アッセイと並行して活性成分を単離・構造決定をするとともに、同定した化合物の類縁体の探索、誘導体の作成、活性評価を行った。これらの内容を研究協力者とともに論文と学会で報告してきた

  • 蛍光細胞分析分離装置と次世代シークエンンサを用いた水中生菌の網羅的解析技術の確立

    研究期間:

    2013年04月
    -
    2016年03月
     

     概要を見る

    本研究では,分離培養に依存しない解析手法として,蛍光細胞分析分離装置および次世代シークエンサーを用いて,水中の細菌叢の網羅的解析手法を確立することを目的とした。国内の浄水場から収集した処理工程水試料を用いて,確立した次世代シークエンサーを用いた手法を培養に基づく従来の遺伝子解析手法と比較した結果,手法の違いによって細菌叢に差が現れた。培養に基づく手法では,Alphaproteobacteria綱が主要だった。一方,次世代シークエンサーを用いた手法では,Alphaproteobacteria綱およびGammaproteobacteria綱が主要であり,多様な綱に属する細菌が検出された

  • 難治性感染症の原因となる休止細菌の分子機構解明

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(挑戦的萌芽研究)

    研究期間:

    2015年
    -
    2016年
     

  • 難治性感染症の原因となる休止細菌の分子機構解明

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(挑戦的萌芽研究)

    研究期間:

    2015年
    -
    2016年
     

     概要を見る

    代謝活性を止めている休止細菌は,抗生物質存在下において生存できるため,感染症難治化の原因となる。本研究では,細菌の細胞骨格であるFtsZに着目し,細胞分裂時のZ-ringの形成を蛍光共鳴エネルギー移動で検出する遺伝子組換え大腸菌株の開発を行った。その結果,セルソーターを用いることで休止細菌と分裂細菌の分離に成功し,休止細菌は抗生物質(オフロキサシン)に対して高い抵抗性を持つことがわかった。また,トランスクリプトーム解析の結果,休止細菌は乳酸デヒドロゲナーゼの遺伝子発現を亢進させていることがわかった。さらに,マイクロ流体デバイスを用いたシングルセル観察によっても上記の結果が支持された

  • 微生物を介した大腸炎寛解プロセスのシステム論的制御

    研究期間:

    2011年04月
    -
    2015年03月
     

     概要を見る

    本研究では、腸管の炎症抑制および腸上皮タイトジャンクションバリア機能の回復に寄与する腸内細菌を同定した。さらに、実験的腸炎マウスモデルを用いて、腸炎の寛解プロセスに寄与する腸内細菌および代謝産物のスクリーニングを行った。また、大腸陰窩における上皮細胞の増殖・分化機構の時空間的ダイナミクスを表現するシミュレーターの開発に成功した

  • 蛍光細胞分析分離装置と次世代シークエンンサを用いた水中生菌の網羅的解析技術の確立

    科学研究費助成事業(国立保健医療科学院)  科学研究費助成事業(基盤研究(B))

    研究期間:

    2013年
    -
    2015年
     

     概要を見る

    本研究では、はじめに蛍光細胞分析分離装置を用いた水中に存在する生菌の分離手法について検討した。既往研究および染色キット記載のプロトコルを参考にして、環境微生物試料を対象に生菌・死菌染色を実施したが、蛍光顕微鏡による目視の観察では生菌・死菌サンプルの蛍光の差に大きな違いが見られなかった。蛍光細胞分析分離装置では、両者に蛍光の差は見られたものの、明確に分離されなかったため、染色条件の適正化が不可欠であると考えられた。また、実際に分離された試料を顕微鏡観察し、細胞数を計数した結果、装置上でのカウント数と必ずしも一致が見られなかったことから、装置上での分離条件についてもさらに検討を行う必要がある。
    次世代シークエンサを用いた水中に存在する細菌の網羅的解析技術についても検討を行った。国内複数の水道水源、浄水場工程水を対象とした。ポリカーボネイト製のメンブレンフィルターを用いて細菌の濃縮を行った後、核酸を抽出した。16S rRNAを対象としたTailed PCRを実施した後、次世代シークエンス解析(アンプリコンシークエンス)に供した。その結果、試料の種類に係わらず、簡便に膨大な細菌叢の情報を得ることができた。微生物の多様性の指標であるChao1を用いて評価した場合、1試料あたり10万リード以上得ることで、その試料中に含まれるほとんどの細菌群を捉えることができることが分かった。97%の相同性でグルーピングした場合、1試料あたり約5,000 OTUsが得られた。また、浄水場工程水で見た場合、処理が進むにつれて多様性が低下したことから、水道原水中に除去されやすい細菌とされにくい細菌が存在しており、されにくい細菌がろ過池から流出していると考えられた。

  • 蛍光細胞分析分離装置と次世代シークエンンサを用いた水中生菌の網羅的解析技術の確立

    科学研究費助成事業(国立保健医療科学院)  科学研究費助成事業(基盤研究(B))

    研究期間:

    2013年
    -
    2015年
     

     概要を見る

    本研究では、はじめに蛍光細胞分析分離装置を用いた水中に存在する生菌の分離手法について検討した。既往研究および染色キット記載のプロトコルを参考にして、環境微生物試料を対象に生菌・死菌染色を実施したが、蛍光顕微鏡による目視の観察では生菌・死菌サンプルの蛍光の差に大きな違いが見られなかった。蛍光細胞分析分離装置では、両者に蛍光の差は見られたものの、明確に分離されなかったため、染色条件の適正化が不可欠であると考えられた。また、実際に分離された試料を顕微鏡観察し、細胞数を計数した結果、装置上でのカウント数と必ずしも一致が見られなかったことから、装置上での分離条件についてもさらに検討を行う必要がある。
    次世代シークエンサを用いた水中に存在する細菌の網羅的解析技術についても検討を行った。国内複数の水道水源、浄水場工程水を対象とした。ポリカーボネイト製のメンブレンフィルターを用いて細菌の濃縮を行った後、核酸を抽出した。16S rRNAを対象としたTailed PCRを実施した後、次世代シークエンス解析(アンプリコンシークエンス)に供した。その結果、試料の種類に係わらず、簡便に膨大な細菌叢の情報を得ることができた。微生物の多様性の指標であるChao1を用いて評価した場合、1試料あたり10万リード以上得ることで、その試料中に含まれるほとんどの細菌群を捉えることができることが分かった。97%の相同性でグルーピングした場合、1試料あたり約5,000 OTUsが得られた。また、浄水場工程水で見た場合、処理が進むにつれて多様性が低下したことから、水道原水中に除去されやすい細菌とされにくい細菌が存在しており、されにくい細菌がろ過池から流出していると考えられた。

  • 潜在的病原性を有する口腔難培養菌の分離培養戦略

    科学研究費助成事業(聖マリアンナ医科大学)  科学研究費助成事業(挑戦的萌芽研究)

    研究期間:

    2011年04月
    -
    2013年03月
     

     概要を見る

    従来の培養法では培養できない常在菌を高効率に培養し取得する目的で、多孔性中空糸膜を応用したヒト口腔内で使用可能な口腔バイオフィルム細菌培養装置を開発し運用した。このシステムは、通常の培養方法に比べ、より高い効率での培養が可能であった。しかし、取得した菌株の新規性と多様性については、期待した程の優位性は見られなかった。新規性の高い菌株の取得には、装置および運用法の更なる改良が必要であると考えられる

  • 潜在的病原性を有する口腔難培養菌の分離培養戦略

    研究期間:

    2011年04月
    -
    2013年03月
     

     概要を見る

    従来の培養法では培養できない常在菌を高効率に培養し取得する目的で、多孔性中空糸膜を応用したヒト口腔内で使用可能な口腔バイオフィルム細菌培養装置を開発し運用した。このシステムは、通常の培養方法に比べ、より高い効率での培養が可能であった。しかし、取得した菌株の新規性と多様性については、期待した程の優位性は見られなかった。新規性の高い菌株の取得には、装置および運用法の更なる改良が必要であると考えられる

  • 潜在的病原性を有する口腔難培養菌の分離培養戦略

    科学研究費助成事業(聖マリアンナ医科大学)  科学研究費助成事業(挑戦的萌芽研究)

    研究期間:

    2011年
    -
    2012年
     

     概要を見る

    従来の培養法では培養できない常在菌を高効率に培養し取得する目的で、多孔性中空糸膜を応用したヒト口腔内で使用可能な口腔バイオフィルム細菌培養装置を開発し運用した。このシステムは、通常の培養方法に比べ、より高い効率での培養が可能であった。しかし、取得した菌株の新規性と多様性については、期待した程の優位性は見られなかった。新規性の高い菌株の取得には、装置および運用法の更なる改良が必要であると考えられる。

  • 微生物機能を利用した資源循環型水環境プロセスの構築

    文部科学省 

    研究期間:

    1999年
    -
    2003年
     

  • メンブレンエアレーション型浄化システムによる畜産排水の高度処理

    研究期間:

    2000年
    -
     
     

  • 中国回収衛星による化合物半導体の単結晶成長に関する研究

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(国際学術研究)

    研究期間:

    1996年
    -
    1997年
     

     概要を見る

    本研究では,中国回収衛星を利用した微小重力場において,In_<1-x>Ga_xSb化合物半導体の単結晶成長実験を行い,結晶溶解・成長過程における拡散及び界面律速過程や面方位依存性を明らかにし,In_<1-x>Ga_xSb化合物半導体のみならず,各種化合物半導体単結晶の高品質化への知見を得ることを目的としている。
    本年度は1996年10月に実施した宇宙実験の試料及び地上対照実験試料を切断し,切断面におけるGaSb溶解領域及びIn_<1-x>Ga_xSb成長領域を電子線マイクロプローブ分析法(EPMA)により測定した。その結果,宇宙試料は長さ方向に平行に溶解し,地上試料は重力方向に末広がりに溶解していた。これは,地上試料では,比重の大きいInSbが重力方向に移動し,より多くのGaSbを溶解したものと考えられる。また,数値シミュレーションを実施した結果,実験結果と同様の結果が得られた。さらに,面方位依存性に着目してみると,両試料とも(lll)A面より(lll)B面の方がInSbに溶解し易いことが明らかになった。反対に,成長領域は,B面よりもA面の方が大きいことが明らかになった。
    なお本年度は,研究討論等を行うため,5月及び8月に延べ3名(早大:平田,村上,桜井)が中国に出張した。また,研究成果の発表のために,8月には中国,10月にはイタリアへ延べ2名(早大:桜井)が出張した。12月には2名(静大:早川,早大:桜井)が本研究の総括討論をするために,訪中した。

  • 微小重力場における化合物半導体単結晶育成時のマランゴニ対流現象機構の解明

     概要を見る

    本研究では、単結晶育成時における温度差と濃度差に起因するマランゴニ対流の相互干渉機構を厳密に解明し,それに基づいたマランゴニ対流の抑制・促進等の制御手法を確立し,単結晶の高品質化手法を確立することを目的として研究を行っている。本年度は、前年度に引き続き,半導体単結晶育成の一つである水平ブリッジマン法によりInSb結晶成長実験を行い,初期融液濃度を変化させることにより温度差および濃度差マランゴニ対流が同方向に作用する系(促進系)と,互いに逆方向に作用する系(抑制系)の融液自由界面上の界面流速を測定した。その結果,抑制系においては,自由界面流れの方向が、融液から結晶方向(温度差マランゴニ対流による)及び結晶から融液方向(濃度差マランゴニ対流による)が同時に存在し,流動の淀み点(2方向の流れが衝突する点)が存在する場合があることが明らかになった。これは,同時に行った数値シュミュレーションからも同様の結果が得られた。さらに抑制系に関しては,航空機を利用した微小重力場においても実験を実施した。その際,放物飛行中の到達重力レベルを変化させ,自然対流が融液自由界面流れに及ぼす影響を観察した。その結果,本実験系においては,自然対流は表面流速にはほとんど影響を及ぼさないことが明らかになった。以上の結果から,結晶成長時の融液側移動現象が,自然対流よりも,結晶成長時の偏析現象に伴う濃度差マランゴニ対流に強く影響を受けることが明らかになった

  • 機能性polymer brushを利用した生体高分子の高速三次元集積化

     概要を見る

    まず,多孔性膜の界面からpolymer brushがはえている構造を作成するために,以下のような手順で膜材料を合成した.中空糸状の多孔性膜(ポリエチレン製)に電子線を照射した後,エポキシ基をもつモノマー(グリシジルメタクリレート)を前駆体としてグラフト重合させた。その後,エポキシ基の一部をイオン交換基(ジエチルアミノ基)に,残りをアルコール性水酸基(エタノールアミノ基)へ変換した.この多孔性膜の膜間に圧力をかけて溶液を透過させ,牛血清アルブミン(BSA)を対流に乗せてpolymer brushまで運び,きわめて短時間で生体高分子集合体を創製できることを確認した。この膜材料に一定流量でBSA溶液を透過させたときの圧力損失は,BSAの吸着が進むにつれて増大する。楕円球の形をしたBSA分子がpolymer brushに最密充填的に吸着していると仮定し,BSAの吸着によって液の透過できる細孔径が減少したとすると、BSA吸着後の膜の透過圧力をHagen-Poiseuille式によって推算できる。この理論式より推算された透過圧力と圧力センサーにより実測した透過圧力を比較した.その結果,実験値と推算値はよく一致することがわかり,吸着容量から推測した多層吸着構造モデルの妥当性が,流体力学的側面からも裏付けられた。また,polymer brush中のイオン交換基密度の増加とともに,電荷が互いに反発してpolymer brushが表面法線方向に伸長し,タンパク質をより多く抱き込む形態をとることが推察された。さらに,生理活性を有する酵素であるウレアーゼをpolymer brushにいったん集積させ,つづいてイオン強度を上げることによって脱離させた。尿素の分解特性をもとに生理活性を評価した結果,polymer brushへの集積前後においてウレアーゼの生理活性は変化しないことが示された。よって、polymer brushは生理活性を維持したまま高密度に生体高分子を集積できる場であることが示唆された

  • 写真関連産業における廃棄物リサイクル手法の評価およびゼロエミッション化の検討

     概要を見る

    写真関連産業での現像液や定着液の使用状況・使用工程を調査し,排出の削減・防止策を提出することを目的として研究を行った。本年度は特に定着廃液を取り上げ,その物質フローの解析と再生技術の評価を行った。また,写真廃液の生物処理を実際に行い,写真廃液中に含まれる成分の生分解性を明らかにした。定着液の再生の際に必要となるのが(A)脱銀,(B)界面活性剤等の除去,(C)ハロゲン除去,(D)成分調整である。このうち,(A)および(C)の工程が必要なのは,銀,ハロゲンの残存によって定着速度が遅くなるからである。また,(B)は(C)のハロゲン除去を妨害するためである。各工程での必要技術は以下の通りであることがわかった。(A)廃液の再生に適している脱銀方法は,添加物や溶出物がない電解法である。電解法により脱銀を行うときは,電位の制御により硫化銀の生成を抑え,陰極室と陽極室をイオン交換膜等で分離して硫黄の生成を抑制する必要がある。(B)界面活性剤,現像主薬酸化物等は活性炭吸着あるいは膜分離法により除去することが望ましい。(C)硬膜剤として含まれるアルミニウムイオン(3価)や,ハロゲン化銀溶解剤として含まれるチオ硫酸イオン(2価)は保持し,ハロゲンイオンのみを除去するために1価選択性イオン交換膜を用いて電気透析を行う。(D)最後に成分の調整をする際,pHや各々の成分には最適な値が存在する。さらに,混合培養系で長期馴養した微生物群を用いて,写真廃液を生物分解した結果,1,000ppm程度のTOC成分が残存した。写真廃液を生物処理のみで完全無害化するためには,難生分解性の有機化合物(EDTAなど)を分解する特殊な細菌が必要であることが示唆された

  • 天然タンパク質の加水分解による生理活性ペプチドの新しい抽出合成法

     概要を見る

    本研究では、(1)原料蛋白質としてトウモロコシ蛋白質(zein)を取り扱い、蛋白質加水分解酵素を用いた加水分解反応によって、所望のペプチド(例えばアンジオテンシン変換酵素(ACE)の阻害ペプチド)の選択的生成を制御する事、及び(2)有機溶媒中において高い機能を発現する酵素材料を開発する事、を目的に研究を行い、以下の成果を得た。1.蛋白質加水分解反応の制御手法の開発ポリマーが形成する有機溶媒二相系において、thermolysinを用いてトウモロコシ蛋白質α-zeinの加水分解反応を行う事によって、zeinが選択的に上相へ、限定加水分解物が両相へ、低分子量ペプチドが下相へ選択的に分配するプロセスを実現し得る事が判った。本研究によって提案した手法は、従来の均一系反応媒体中における蛋白質加水分解反応の問題点(生成物の選択的合成や、酵素と生成物の分離が困難)を解決し得る技術である。2.有機溶媒中で機能する新しい酵素材料の開発有機溶媒中で機能する新しい酵素の使用形態として、酵素とポリマーの物理的な吸着によって形成したハイブリッド型酵素材料「ポリマー・酵素複合体」を提案した。-分子のα-chymotrypsinに-分子のPEGが吸着した酵素-ポリマー複合体を調製したところ、著しく活性が向上する事が明らかになった。疎水性の強い緩衝剤、及び両親媒性ポリマーを用いた際に、活性が高い複合体が得られた。ホウ酸-コハク酸系緩衝液を用いて調製したPEG4000-α-chymotrypsin複合体(モル比8:1)はイソオクタン中においてnative α-chymotrypsinの約8000倍の活性を発現した。本手法は、水溶性の生体触媒を有機溶媒中で機能させる新しい手法であり、その新規性・波及効果は極めて高いと考えられる。本新規酵素は有機溶媒二相系においても高い活性を発現し、蛋白質加水分解反応等に応用可能である事が示された

  • 写真関連産業における廃棄物リサイクル手法の評価およびゼロエミッション化の検討

     概要を見る

    写真関連産業での現像液や定着液の使用状況・使用工程を調査し,排出の削減・防止策を提出することを目的として研究を行った。本年度は特に定着廃液を取り上げ,その物質フローの解析と再生技術の評価を行った。また,写真廃液の生物処理を実際に行い,写真廃液中に含まれる成分の生分解性を明らかにした。定着液の再生の際に必要となるのが(A)脱銀,(B)界面活性剤等の除去,(C)ハロゲン除去,(D)成分調整である。このうち,(A)および(C)の工程が必要なのは,銀,ハロゲンの残存によって定着速度が遅くなるからである。また,(B)は(C)のハロゲン除去を妨害するためである。各工程での必要技術は以下の通りであることがわかった。(A)廃液の再生に適している脱銀方法は,添加物や溶出物がない電解法である。電解法により脱銀を行うときは,電位の制御により硫化銀の生成を抑え,陰極室と陽極室をイオン交換膜等で分離して硫黄の生成を抑制する必要がある。(B)界面活性剤,現像主薬酸化物等は活性炭吸着あるいは膜分離法により除去することが望ましい。(C)硬膜剤として含まれるアルミニウムイオン(3価)や,ハロゲン化銀溶解剤として含まれるチオ硫酸イオン(2価)は保持し,ハロゲンイオンのみを除去するために1価選択性イオン交換膜を用いて電気透析を行う。(D)最後に成分の調整をする際,pHや各々の成分には最適な値が存在する。さらに,混合培養系で長期馴養した微生物群を用いて,写真廃液を生物分解した結果,1,000ppm程度のTOC成分が残存した。写真廃液を生物処理のみで完全無害化するためには,難生分解性の有機化合物(EDTAなど)を分解する特殊な細菌が必要であることが示唆された

  • 食料産業におけるゼロエミッション化のための新しい排水処理システム

     概要を見る

    食品産業は生物系由来の原料が多いため,有機物の循環,すなわちバイオサイクルという観点から,食品産業排水中の成分は原料生産へフィードバックすることが可能である。しかしながらバイオサイクルという流れから見たときに,どのような排水処理がエミッション低減に有効かはっきりとしていない。そこで,このバイオサイクルに出入りする物質およびエネルギーを定量的に把握し,排水処理方式がこれらの値に及ぼす影響を数値化することによって,ゼロエミッションをめざした排水処理プロセスの構築を検討することが本研究の目的である。まず,ワイン製造プロセスについて原料,廃棄物および排水処理に関するアンケート取材を行った。その結果,ワイン製造プロセスについて,炭素重量基準での詳細な物質フローを求めることができた。次に,バイオサイクルに出入りする物質およびエネルギーを定量的に評価するため,独自のフローシートを提案し,微生物増殖速度式や化学量論式に基づいた評価式を作成した。そして,嫌気処理および好気処理を行った場合に発生する汚泥量などのエミッションを定量的に把握し,さらに汚泥を廃棄物と混ぜて堆肥化した場合やメタン回収した場合のエネルギー収支を算出した。今回収集したワイン製造排水に関するデータを用いて試算を行った結果,発生/使用堆肥量の関係から,汚泥を堆肥化して原料生産へ用いることは量的に可能であることが分かり,バイオサイクルが機能する可能性を示唆することができた。また,汚泥や廃棄物を堆肥化することによって削減できる化学肥料の量およびその生産に要するエネルギーを見積もった結果,バイオサイクルに投入されるエネルギーをかなりの割合で節約できることがわかった。一方,嫌気処理によって節約できるエネルギーおよび回収できるエネルギーはこの10分の1程度であることもわかった

  • 高品質単結晶育成を目指した微小重力場におけるマランゴニ対流の解明

     概要を見る

    融液成長法によって育成される半導体単結晶の高品質化手法の開発・確立を目的として,融液内のマランゴニ対流現象を解明するため,次の研究を行った.まず,温度差に起因する界面張力差に基づく駆動力の増大に伴い,液柱内のマランゴニ対流が二次元層流から三次元層流を経て三次元振動流へと遷移することを明らかにし,その機構を詳細に解析した.具体的には,微小液柱実験装置を用いた地上及び微小重力実験により,微小重力場では,地上で観察された超安定領域が消滅することを明らかにした.また,マランゴニ対流に起因する液柱内の温度振動状態が,定常層流,周期的伸縮振動,周期的回転振動,準周期的振動,そしてカオス振動のいずれかに分類できることを明らかにし,温度振動状態を表すモデル式を提出した.このモデル式は実験結果とよく一致しており,このモデル式より,各振動状態の特徴を明確に表すことができた.また,これらの遷移プロセスは液柱の形状・体積や重力レベルなどに依存することを明らかにした.また,非定常数値計算コードを開発し,落下塔実験で生ずる1GからμGへの重力のステップ変化に伴う固液界面上の熱流束を解析した.得られた数値解析結果は,実験結果と良好な一致を示し,熱移動現象を充分に良く説明することができた.さらに詳細に検討した結果,液柱長さを代表長さとした無次元座標,流動の駆動力を表すマランゴニ数,流体熱物性を表すプラントル数を導入することにより,固液界面上の熱流束分布を統一的に評価し得る事を明らかにした.また,宇宙環境においても存在する残存重力が融液の不安定化に及ぼす影響を検討するために,拡散係数測定法のひとつであるLong Capillary法を模擬した数値計算も行い,融液内の対流発生と残存重力の関係を明らかにした.以上の成果は,融液内のマランゴニ対流現象の微細機構を明らかにしたものであり,融液成長法による育成単結晶の高品質化ための操作条件決定などに有益なものと考える

  • 食品産業におけるゼロエミッション化のための新しい排水処理システム

     概要を見る

    食品産業から排出される排水や廃棄物は生物由来の易分解性有機物中心である.そのため,有機物の循環,すなわちバイオサイクルという点から見て,これらの排出物は原料生産へフィードバックすることが可能である.廃棄物の処理および再生に関しては,現在さまざまな方法が開発・使用されているが,食品産業におけるバイオサイクルという流れから見た時に,どの方法がエミッション低減に有効であるかは,はっきりとしていない.本研究では原料生産と製品製造を一連のプロセスと考え,このバイオサイクルに出入りする物質およびエネルギーを定量的に把握し,その中でのゼロエミッション化をめざすことを目的とした.本研究では具体的な対象産業としてワイン醸造産業を選んだ.まずブドウ(生果)から作るワインの製造プロセスにターゲットを絞り,アンケート調査を行うことによって物質収支のフロー解析を行った.20,000kgのブドウから17,280Lのワインが生産される過程で,梗,果実・種,澱等約3,900kgの固形廃棄物,100tの排水が出ることがわかった。また,排水の処理工程(活性汚泥法)において発生する余剰汚泥量は,乾燥重量として68.6kgであることがわかった.次に原料および各廃棄物・排水について重量および元素分析(C,N,P)を行い,製造プロセス内における元素ごとのフロー解析を行った.元素によって動きが異なるものの,固形廃棄物(ブドウ梗・ブドウ粕)としての排出が大きな割合を占めることがわかった.特に窒素とリンに関しては,バイオサイクルへのインプットが主に肥料からであることを踏まえればこれらを有効的に農地還元させることがバイオサイクルを機能させる上で重要であるといえる.これらは含水率が低く,C/N比が高いので,先に述べた余剰汚泥のコンポスト化を行う際の調整剤となりうることが示唆された

  • 畜産系排水の高度処理をめざしたメンブレンエアレーション型浄化システムの開発

     概要を見る

    本研究は小規模畜産農家でも導入できる小型で高効率な有機物・窒素除去システムの確立を目指し,単一槽内において窒素除去が可能なメンブレンエアレーション型バイオフィルムリアクタ(MABR)を開発し,その評価を行ったものである。1.生物膜内溶存酸素(DO)濃度分布解析先端径数μmのDO微小電極を作製し,生物膜内のDO濃度分布を測定した結果,生物膜厚みが大きいものは嫌気部位が存在することを明らかにした。この結果は生物膜厚みおよび酸素の供給速度を制御することにより,生物膜内に局所的に異なる反応場を創生することが可能で,単一槽内もしくは単一生物膜内において硝化・脱窒同時反応が起こせることを示唆している。2.MABRコンセプトの実現と処理能評価易分解性である生活模擬排水を用いて連続運転による有機物・窒素の同時除去試験を行い,MABRのコンセプトを実現できるかどうかを評価した。運転開始後50日目以降,有機炭素および窒素の除去率はともに90%以上を達成し,コンセプト通り単一槽内にて有機物・窒素を逐次的に除去することに成功した。3.MABRの畜産系排水への適用とその評価生活模擬排水への知見を応用し,MABRの畜産系排水への適用性について検討した。約1年間の長期運転で有機炭素および窒素成分の平均除去率96%,83%を得た。また,メンブレン表面積当たりの窒素除去速度は4.48g-N/(m^2・day)であり,生物膜内で高効率に窒素除去が行われていることを示した。生物膜内のDO濃度および微生物生態分布を解析した結果,生物膜内で好気・嫌気部位が存在し,その環境に応じた微生物群が生息していることを確認した。また,硝酸を経由しない亜硝酸型脱窒が主な窒素除去経路であることが推察された。以上より,MABRを用いることにより,窒素成分の比率が高い畜産系排水においても単一槽で高効率に窒素を除去できることが示唆された

  • バブルカラムリアクターを用いたAOP法による地下水からの有機塩素化合物の除去

     概要を見る

    有機塩素化合物は脱油脂やドライクリーニングなどさまざまな分野で使用されているが,発ガン性や催奇性があるため,土壌中から地下水に浸透した場合,飲料水として使うことは不可能である。地下水については光触媒反応を利用して有機塩素化合物の分解が試みられているが,地下水中に含まれているミネラル分がヒドロキシラジカルのスカベンジャーとして作用するため,効率が上がらない。本研究では,有機塩素化合物ガスを脱イオン水へ移動させ,紫外線(UV)ランプを備えた気泡塔型UVリアクター内で分解する手法を提案した。この手法における最大のメリットは,リアクター内の有機塩素化合物がUVランプからの光子や,気液界面ならびにバルク液相でのヒドロキシラジカルと反応できるため,高速かつ副生成物の少ない分解処理が可能になる点である。本研究では,上記リアクター内における物質移動および有機塩素化合物ガス分解の速度論的解析を行い,装置設計や操作条件の最適化を行った。その結果,テトラクロロエチレン(PCE)を対象汚染物質とした場合,PCE/過酸化水素の化学量論比がPCE分解速度に大きく影響を与えることがわかった。また,PCE分解の初期段階で塩素原子がはずれて塩化物イオンが生成し,これらの蓄積がPCE分解速度に影響を与えることもわかった。次に,各種センサーを備えた気泡塔型紫外線リアクターの作製を行い,空隙率分布の影響を確認するために,UVランプの近傍に局所的に気泡が集中するような多孔質板,およびUVランプの周りに均一に気泡が生成するようなリングタイプの散気板を用いて実験を行った。その結果,まず,UVランプ近傍の空隙率の分布を特殊な導電率プローブを用いてオンラインでモニタリングすることに成功した。また,空隙率の分布が反射・散乱などの効果により光の吸収に影響を与えることを明らかにした

  • 微生物生態系を制御した高性能窒素・リン同時除去型排水処理システムの開発

     概要を見る

    本研究では,様々な産業から排出される排水中の窒素・リンを高効率に除去する高度処理システムの開発に取り組んだ。特に,小規模事業場へも導入可能な単一槽型栄養塩除去プロセスである嫌気/好気/無酸素(AOA)プロセスの開発を行い,長期間にわたる安定した除去性能維持の実現をめざした。また,AOAプロセスとメンブレンエアレーション法を組み合わせることにより,槽内の微生物生態系を制御し,外部から基質を添加せずに窒素・リン同時除去に成功した

  • 複合微生物系シミュレーションモデルの構築に基づくシステム微生物生態学の創生

     概要を見る

    環境中では多種多様な微生物が雑多に存在する複合微生物系を形成している。本研究では個々の微生物の現象に着目するのではなく,生態系全体を一つのシステムとしてとらえるシステムバイオロジーの概念を微生物生態学に導入し,実験的手法および知識工学的手法を併用してコンピュータ上に微生物のコミュニティーを再構築し,微生物生態形成メカニズムの真の理解につなげる新規方法論を確立・提案することを目的とした。本研究では,特に,複合微生物系の一例として,多孔質膜を介して通気を行い,膜上にバイオフィルムを形成させる方法(いわゆるメンブレンエアレーション法)によって得られたバイオフィルムを取り上げた。本年度は,シミュレーション結果の精度に多大な影響を与える微生物パラメータを精査し,シミュレーション結果と実験結果を比較した。まず,バイオフィルムからサンプリングした従属栄養細菌(HB),アンモニア酸化細菌(AOB),亜硝酸酸化細菌(Nitrobacter,Nitrospira)を対象に,水質回分実験・呼吸活性実験・蛍光遺伝子プローブ法(FISH法)・レクチン染色・画像解析を行い,それぞれの徴生物の活性パラメータを評価した。一方,形成されたバイオフィルムを壊さずに,微小電極測定およびFlSHを行い,バイオフィルム内の基質濃度分布と微生物分布を得た。つぎに,この結果を,すでに得られた微生物パラメータを用いてシミュレートした結果と比較した。完全には実験結果をシミュレーションでは再現することはできなかったが,文献値のパラメータを用いてシミュレーションをした結果と比較して,多くの部分の傾向を再現することができるようになった。またMABの内部に存在する亜硝酸酸化細菌はNitrobacterであることが明らかになった

  • 海洋中深層における非極限性古細菌の分子生態学的研究

     概要を見る

    近年の研究から、海洋の中心層には古細菌が広く分布することが分かってきた。1000m以深では、数的には原核生物のうちの半数近くを占めることが見出されてきたが、今のところ分離株が全くなく、その生態、系統、物質循環に対する寄与などについては殆ど未知の状況である。これらの環境は低温、高圧、貧栄養で特徴付けられるが、こうした環境は従来から知られていた古細菌の好熱性、好塩性、嫌気性などの性質からはずれがある。従ってこれらを非極限性の古細菌と呼ぶことにする。本研究はこの一群を中心とした古細菌に対する学際的研究である。本研究では様々な課題を扱ったが、最大の成果は外洋域中心層から複数の古細菌を分離し、その系統的位置づけおよび性情等についての検討を開始できたことである。これは我々の知る限り、世界で初めてのことである。さらに、それが系統的には好塩性の古細菌に近縁であることが分かったことから、非極限性古細菌群集の起源や古細菌の進化上の広がりなどについて新たな仮説を提示できる段階に至った

  • 機械的刺激による血管弾性線維形成機序の解明

     概要を見る

    血管弾性線維は動脈の構造を保つ上で極めて重要な要素であり、その破綻は老化や血管病と密接に関係している。血管特有のなんらかの機械的刺激が弾性線維形成に影響を及ぼすことが推定される。そこで本研究では機械的刺激の種類や強度などの変化が血管弾性線維形成に及ぼす影響について解明することを目的に研究を行った。ラット胎仔から採取した大動脈血管平滑筋細胞を用いた実験では、細胞の積層化や伸展刺激によって、平滑筋細胞分化がより亢進し、血管弾性線維形成が促進されることが分かった

  • 膜分離活性汚泥法の膜の目詰まりを抑制する酵素固定化型ろ過膜の開発

     概要を見る

    本研究は膜分離活性汚泥法における微生物由来のろ過膜の目詰まりを抑制するため、酵素を固定化したろ過膜を開発した。放射線グラフト重合法を適用し、ポリエチレン製精密ろ過膜をグラフトし、グラフト鎖に親水性の高い官能基を導入した。これにより、元のポリエチレンと変わらない高い透水性を確保することができた。次に、微生物が産生する微生物細胞間情報伝達物質を分解可能な酵素を固定化した。微生物細胞間情報伝達物質を介してバイオフィルム形成を行うAgrobacterium tumefaciensを供試細菌として、作製したしたろ過膜へのバイオフィルム形成試験を行った。この酵素固定化型ろ過膜を用いることで、バイオフィルムの形成を大幅に削減できた

▼全件表示

講演・口頭発表等

  • 一過性の遺伝子発現の履歴を可視化する技術の開発

    関本美樹, 山本尚輝, 河合祐人, 木賀大介, 常田聡

    第34回日本バイオフィルム学会学術集会   (新潟(オンライン))  日本バイオフィルム学会学  

    発表年月: 2020年08月

  • ldhA発現によるpersister形成機構

    大野友梨乃, 山本尚輝, 常田聡

    第34回日本バイオフィルム学会学術集会   (新潟(オンライン))  日本バイオフィルム学会  

    発表年月: 2020年08月

  • Enrichment of comammox Nitrospira from nitrifying granules by using fixed-bed continuous feeding bioreactors

    8th IWA Microbial Ecology and Water Engineering Specialist Conference  

    発表年月: 2019年11月

  • Genomic and physiological characteristics of a novel nitrite-oxidizing Nitrospira strain isolated from a drinking water treatment plant

    8th IWA Microbial Ecology and Water Engineering Specialist Conference  

    発表年月: 2019年11月

  • RNase 活性を指標とした微生物増殖water-in-oil ドロップレットの検出法 “FNAP-sort” の確立

    第71回日本生物工学会大会  

    発表年月: 2019年09月

  • Water-in-oil ドロップレットを用いた腸内細菌培養手法の開発

    第71回日本生物工学会大会  

    発表年月: 2019年09月

  • 亜酸化窒素還元能を持つ硝化細菌Nitrobacter の発見

    第33回日本微生物生態学会  

    発表年月: 2019年09月

  • 細胞ごとに増殖速度のばらつきが大きいアンモニア酸化細菌のしなやかな生存戦略

    第33回日本微生物生態学会  

    発表年月: 2019年09月

  • 従属栄養細菌との相互作用を介した硝化菌の増殖促進機構

    第33回日本微生物生態学会  

    発表年月: 2019年09月

  • Water-in-oil ドロップレット内での環境微生物の培養とシングルドロップレットアイソレー ション技術の開発

    第33回日本微生物生態学会  

    発表年月: 2019年09月

  • Enrichment of comammox Nitrospira from nitrifying granules by using fixed-bed continuous feeding bioreactors

    6th International Conference on Nitrification and Related Processes  

    発表年月: 2019年09月

  • Enrichment of comammox and canonical Nitrospira from acidic soil: Insights into niche differentiation and adaptation to low pH

    6th International Conference on Nitrification and Related Processes  

    発表年月: 2019年09月

  • A flexible survival strategy of ammonia-oxidizing bacteria by growth heterogeneity at a single cell level

    6th International Conference on Nitrification and Related Processes  

    発表年月: 2019年09月

  • Physiological and Genomic Characteristics of a New "Candidatus Nitrotoga" Isolate

    6th International Conference on Nitrification and Related Processes  

    発表年月: 2019年09月

  • Sequence-specific endoribonucleolytic toxin, MazF, conserved in nitrifying bacteria

    6th International Conference on Nitrification and Related Processes  

    発表年月: 2019年09月

  • Dormant and metabolic-active persister formation in Escherichia coli mediated by the expression of lactate dehydrogenase A

    8th Congress of European Microbiologists  

    発表年月: 2019年07月

  • Mixotrophic Lifestyle of Nitrite Oxidizer Nitrotoga in the Presence of Pyruvate

    8th Congress of European Microbiologists  

    発表年月: 2019年07月

  • Cultivation of a bacterium representing a previously unrecognized clade of the Nitrosomonas group; physiology, genomics, and distribution of a missing ammoniaoxidizer

    8th Congress of European Microbiologists  

    発表年月: 2019年07月

  • 緑膿菌バイオフィルム中のDormant cells 亜集団の選択的プロテオミクスおよび時空間動態解析

    第33回日本バイオフィルム学会学術集会  

    発表年月: 2019年07月

  • 未培養硝化菌を対象とした新規分離培養技術の開発

    環境バイオテクノロジー学会2019年度大会  

    発表年月: 2019年06月

  • W/Oドロップレットを用いた環境微生物培養の基盤技術“FNAP-sort”の開発

    環境バイオテクノロジー学会2019年度大会  

    発表年月: 2019年06月

  • 一過性の遺伝子発現の履歴を可視化する技術の開発

    第92回日本細菌学会総会  

    発表年月: 2019年04月

  • Bacterial target-centric view of small RNA regulation revealedby comparative CLIP-seq

    第92回日本細菌学会総会  

    発表年月: 2019年04月

  • エネルギーを貯蓄して抗菌薬に抵抗する大腸菌persisterの形成機構

    第92回日本細菌学会総会  

    発表年月: 2019年04月

  • Effects of gut microbiota disturbance at early life on colonic mucosal immune cells

    第47回日本免疫学会総会学術集会  

    発表年月: 2018年12月

  • エネルギー蓄積を伴う大腸菌persisterの形成機構

    第101回日本細菌学会関東支部総会  

    発表年月: 2018年11月

  • water-in-oilエマルションを用いた微生物の培養および検出技術の構築

    平成30年度日本生物工学会大会  

    発表年月: 2018年09月

  • 亜硝酸酸化細菌におけるToxin-Antitoxin機構の生理学的意義の考察

    平成30年度日本生物工学会大会  

    発表年月: 2018年09月

  • Growth variability at the single-cell level affects culturability of environmental microorganisms

    17th International Symposium on Microbial Ecology  

    発表年月: 2018年08月

  • Genomic and physiological characteristics of novel nitrite-oxidizing Nitrospira isolated from a drinking water treatment plant

    17th International Symposium on Microbial Ecology  

    発表年月: 2018年08月

  • Culture-dependent analyses of isolated Nitrotoga sp. provide deeper insight into the physiology

    17th International Symposium on Microbial Ecology  

    発表年月: 2018年08月

  • Energy metabolism of ldhA-mediated Escherichia coli persisters

    17th International Symposium on Microbial Ecology  

    発表年月: 2018年08月

  • 環境ストレスがpersister形成メカニズムに与える影響

    第32回日本バイオフィルム学会学術集会  

    発表年月: 2018年07月

  • バイオフィルム内環境におけるldhA発現とPersister形成との関係解析

    第32回日本バイオフィルム学会学術集会  

    発表年月: 2018年07月

  • RNAシャペロンHfqによるバイオフィルム環境適応制御機構の理解

    第32回日本バイオフィルム学会学術集会  

    発表年月: 2018年07月

  • 難培養微生物の可培養化を目指したシングルセルレベルでの増殖不均一性の解析

    第32回日本微生物生態学会  

    発表年月: 2018年07月

  • water-in-oilエマルションを利用した微生物培養および分取技術の開発

    第32回日本微生物生態学会  

    発表年月: 2018年07月

  • 病原菌Clostridium perfringens由来トキシン-アンチトキシン機構MazEFの分子認識と生理機能に関する考察

    第32回日本微生物生態学会  

    発表年月: 2018年07月

  • 酸性土壌に由来する新規な亜硝酸酸化細菌Nitrospiraの培養

    第32回日本微生物生態学会  

    発表年月: 2018年07月

  • 分離培養プロセスとゲノム情報から推定する亜硝酸酸化細菌Nitrotogaの生理学的性質および増殖促進条件

    第32回日本微生物生態学会  

    発表年月: 2018年07月

  • 亜硝酸酸化細菌NitrospiraのMazEF機構に着目した環境適応機構の考察

    環境バイオテクノロジー学会2018年度大会  

    発表年月: 2018年06月

  • W/Oエマルションを用いた微生物の培養と分取技術の構築

    環境バイオテクノロジー学会2018年度大会  

    発表年月: 2018年06月

  • Stochastic ldhA expression induces Escherichia coli persister formation irrespective of energy repression

    EMBO Workshop: Bacterial Persistence and Antimicrobial Therapy  

    発表年月: 2018年06月

  • Toxin-Antitoxin機構の分子認識機構: RNA干渉酵素の認識切断配列の同定手法の確立

    第91回日本細菌学会総会  

    発表年月: 2018年03月

  • 大腸菌ldhA発現によるpersister形成メカニズムの解明

    第91回日本細菌学会総会  

    発表年月: 2018年03月

  • 網羅的遺伝子発現解析による硝化菌の形態変化がもたらす生存戦略の解明

    第13回日本ゲノム微生物学会  

    発表年月: 2018年03月

  • 見過ごされたアンモニア酸化細菌:Nitrosomonas属の新規な生理学、ゲノミクス、環境分布

    第13回日本ゲノム微生物学会  

    発表年月: 2018年03月

  • ピルビン酸存在下での亜硝酸酸化細菌Nitrotogaの混合栄養的な増殖様式

    第13回日本ゲノム微生物学会  

    発表年月: 2018年03月

  • Colonic in ammation induces a transient increase in serum LECT2 level

    第46回日本免疫学会総会学術集会  

    発表年月: 2017年12月

  • ldhA発現による大腸菌persister形成と好気代謝制御との関係

    2017年日本細菌学会関東支部インターラボセミナー  

    発表年月: 2017年11月

  • water-in-oilエマルションを用いた微生物培養技術の開発

    平成29年度日本生物工学会大会  

    発表年月: 2017年09月

  • 乳酸発酵遺伝子ldhA発現によるpersister形成とプロトン駆動力との関係

    平成29年度日本生物工学会大会  

    発表年月: 2017年09月

  • Characterization of a chromosomal toxin-antitoxin module conserved in Nitrosomonas europaea

    How Dead is Dead V  

    発表年月: 2017年09月

  • Spatio-temporal dynamics of dormant cells in Pseudomonas aeruginosa biofilm based on bacterial growth activity

    How Dead is Dead V  

    発表年月: 2017年09月

  • Fermentation pulse expression leads to formation of E. coli persister

    How Dead is Dead V  

    発表年月: 2017年09月

  • 完全アンモニア酸化能を保持するComammox細菌の分離培養と生理生態

    環境微生物系学会合同大会2017  

    発表年月: 2017年08月

  • persister形成メカニズムに対する培養環境の影響

    環境微生物系学会合同大会2017  

    発表年月: 2017年08月

  • ゲノムから推定する遅増殖性Nitrotogaの活性促進因子

    環境微生物系学会合同大会2017  

    発表年月: 2017年08月

  • 硝化菌単一菌株集団でみられる形態と増殖能の不均一性

    環境微生物系学会合同大会2017  

    発表年月: 2017年08月

  • 硝化細菌におけるストレス応答機構の解明: Toxin-antitoxin機構はなぜ必要なのか?

    環境微生物系学会合同大会2017  

    発表年月: 2017年08月

  • ldhA発現による大腸菌persister形成と中心代謝経路の関係

    環境微生物系学会合同大会2017  

    発表年月: 2017年08月

  • 細菌の分裂活性をもとにした緑膿菌コロニーバイオフィルム内の休止細菌時空間動態の解析

    環境微生物系学会合同大会2017  

    発表年月: 2017年08月

  • Growth Heterogeneity in Pure Cultures of Nitrifiers

    5th International Conference on Nitrification and Related Processes  

    発表年月: 2017年07月

  • Comparative Genomics of Phylogenetically Distinct Two Nitrospira Strains Isolated from Activated Sludge

    5th International Conference on Nitrification and Related Processes  

    発表年月: 2017年07月

  • Genome-Informed Isolation of Nitrite Oxidizer Nitrotoga sp.

    5th International Conference on Nitrification and Related Processes  

    発表年月: 2017年07月

  • Screening disruptors of the toxin–antitoxin complex in Staphylococcus aureus

    7th Congress of European Microbiologists  

    発表年月: 2017年07月

  • Characterization of a sequence-specific cutter conserved in the Nitrosomonas europaea chromosome

    7th Congress of European Microbiologists  

    発表年月: 2017年07月

  • Stochastic expression of lactate dehydrogenase causes E. coli persister formation

    7th Congress of European Microbiologists  

    発表年月: 2017年07月

  • Analysis of dormant cell dynamics within Pseudomonas aeruginosa biofilm

    7th Congress of European Microbiologists  

    発表年月: 2017年07月

  • ldhA発現を介したpersister形成とプロトン駆動力との関係

    第31回日本バイオフィルム学会学術集会  

    発表年月: 2017年07月

  • 乳幼児期の腸内細菌叢攪乱が食物アレルギー感受性に与える影響解析

    第21回腸内細菌学会  

    発表年月: 2017年06月

  • 乳幼児期の腸内細菌叢の撹乱が腸管炎症制御におよぼす影響解析

    第21回腸内細菌学会  

    発表年月: 2017年06月

  • Modulation of inflammatory response with gut commensal bacteria-derived metabolites

    第90回日本細菌学会総会  

    発表年月: 2017年03月

  • 好気呼吸と発酵のバランスが崩れるとpersisterが形成される

    第90回日本細菌学会総会  

    発表年月: 2017年03月

  • 乳酸脱水素酵素阻害による緑膿菌バイオフィルム除去

    第90回日本細菌学会総会  

    発表年月: 2017年03月

  • なぜ、難培養性細菌の増殖は不均一なのか?-シングルセル観察から見えたクローナル集団の実態-

    第90回日本細菌学会総会  

    発表年月: 2017年03月

  • ldhA遺伝子の確率的な発現による大腸菌のpersister形成

    第90回日本細菌学会総会  

    発表年月: 2017年03月

  • 乳幼児期の腸内細菌叢の撹乱が腸管炎症の抑制的制御機構に与える影響解析

    第19回化学工学会学生発表会 小金井大会  

    発表年月: 2017年03月

  • 緑膿菌バイオフィルム中に存在する非分裂細菌の生理学的機能解明

    第19回化学工学会学生発表会 小金井大会  

    発表年月: 2017年03月

  • 革新的分離培養技術による新規なcomammox細菌の獲得と生存戦略の解明

    第19回化学工学会学生発表会 小金井大会  

    発表年月: 2017年03月

  • 乳幼児期の腸内細菌叢攪乱がアレルギー応答に与える影響解析

    第19回化学工学会学生発表会 小金井大会  

    発表年月: 2017年03月

  • セルソーターによって分取された凝集体内の微生物間相互作用の解明

    第11回日本ゲノム微生物学会  

    発表年月: 2017年03月

  • Nitrospiraの亜硝酸酸化活性を制御するQuorum-sensing機構の発見

    第11回日本ゲノム微生物学会  

    発表年月: 2017年03月

  • 確率的なldhA発現に伴うpersister形成のメカニズム解明

    第5回⽇本⽣物⼯学会東⽇本⽀部コロキウム  

    発表年月: 2017年03月

  • The interaction between commensal bacteria and immune cells regulates acute colitis

    第45回日本免疫学会総会学術集会  

    発表年月: 2016年12月

  • 微生物凝集体ソーティングによる未培養な亜硝酸酸化細菌Nitrotogaの獲得と生存戦略

    第31回日本微生物生態学会  

    発表年月: 2016年10月

  • 大腸菌のpersister形成を誘導する多様な経路

    第31回日本微生物生態学会  

    発表年月: 2016年10月

  • ldhAの確率的な発現によるpersister形成と制御

    第31回日本微生物生態学会  

    発表年月: 2016年10月

  • Quorum-sensing機構による亜硝酸酸化細菌Nitrospira japonicaの活性制御メカニズム

    第31回日本微生物生態学会  

    発表年月: 2016年10月

  • クローナルな硝化菌集団における細胞増殖活性の不均一性の評価と機構解明

    第31回日本微生物生態学会  

    発表年月: 2016年10月

  • Toxin-antitoxin分子認識機構:病原菌由来RNA インターフェレンスの特異的認識配列の同定

    平成28年度日本生物工学会大会  

    発表年月: 2016年09月

  • 病原性微生物を対象としたプログラム細胞死誘導物質の探索

    平成28年度日本生物工学会大会  

    発表年月: 2016年09月

  • Ammonia Concentration Determines Ecological Niche Differentiation of Nitrospira as Nitrite-Oxidizers in Activated Sludge

    6th International Conference Microbial Ecology and Water Engineering (MEWE2016)  

    発表年月: 2016年09月

  • Comparative Genomic Analysis of Phylogenetically Distinct Two Nitrospira Strains Isolated from a Wastewater Treatment Plant

    16th International Symposium on Microbial Ecology  

    発表年月: 2016年08月

  • Exploring Intestinal Bacteria Involved in the Regulation of Farnesoid X Receptor Activity

    16th International Symposium on Microbial Ecology  

    発表年月: 2016年08月

  • Physiological Characterization of Nitrotoga-like Bacteria Enriched from Coastal Sand

    16th International Symposium on Microbial Ecology  

    発表年月: 2016年08月

  • Physiological and Genetic Properties of Nitrosomonas mobilis Ms1 Isolated from Autotrophic Nitrifying Granule of Wastewater Treatment Plant

    16th International Symposium on Microbial Ecology  

    発表年月: 2016年08月

  • Direct Isolation of Microcolonies from Activated Sludge Opens the Window of Unrecognized Genus Nitrosomonas as ammonia oxidizers

    16th International Symposium on Microbial Ecology  

    発表年月: 2016年08月

  • 嫌気代謝遺伝子の発現ノイズによるPersister形成の解析

    第30回日本バイオフィルム学会学術集会  

    発表年月: 2016年07月

  • 新規な分離培養技術によって獲得された硝化細菌の生理・ゲノム特性

    環境バイオテクノロジー学会2016年度大会  

    発表年月: 2016年06月

  • 核内受容体FXRを活性化する腸内細菌の探索

    第20回腸内細菌学会  

    発表年月: 2016年06月

  • 新規な分離培養戦略が切り拓く難培養性硝化細菌の獲得と生理・ゲノム特性

    日本農芸化学会2015年度大会  

    発表年月: 2016年03月

  • 遺伝子発現解析とシングルセル観察から探るDormant Persistersの正体

    第89回日本細菌学会総会  

    発表年月: 2016年03月

  • 常在細菌-TLRsの相互作用を介した腸管炎症制御機構

    第89回日本細菌学会総会  

    発表年月: 2016年03月

  • ストレス環境が誘導する大腸菌休止化経路の解析

    第89回日本細菌学会総会  

    発表年月: 2016年03月

  • 細菌集団中の確率的なldhA発現による休止細菌形成

    第89回日本細菌学会総会  

    発表年月: 2016年03月

  • 三次元数理シミュレーションを利用したバイオフィルム中の休止細菌形成動態の解析

    第89回日本細菌学会総会  

    発表年月: 2016年03月

  • Liver senses gut environmental alteration induced by oral pathobionts

    第89回日本細菌学会総会  

    発表年月: 2016年03月

  • 活性汚泥中に潜在する未培養アンモニア酸化細菌の分離培養

    第30回日本微生物生態学会  

    発表年月: 2015年10月

  • ファージディスプレイ法によるプログラム細胞死誘導物質の探索

    第30回日本微生物生態学会  

    発表年月: 2015年10月

  • シングルセルレベルでのldhA発現のゆらぎと休止細菌形成の関連性

    第30回日本微生物生態学会  

    発表年月: 2015年10月

  • Physiological characterization of Nitrosomonas mobilis-like strain isolated from autotrophic nitrifying granule

    第30回日本微生物生態学会  

    発表年月: 2015年10月

  • Isolation, physiology, and genomics of novel nitrifiers

    第30回日本微生物生態学会  

    発表年月: 2015年10月

  • 遺伝子発現から探る休止細菌の分子機構

    第29回日本バイオフィルム学会学術集会  

    発表年月: 2015年07月

  • 新規分離培養手法を用いたハイスループットなアンモニア酸化細菌の獲得

    環境バイオテクノロジー学会2015年度大会  

    発表年月: 2015年06月

  • Comparative Genomic Analysis of Phylogenetically Distant Two Nitrospira Strains Isolated from a Wastewater Treatment Plant

    4th International Conference on Nitrification  

    発表年月: 2015年06月

  • Isolation and Successful Subculture of Nitrosomonas mobilis Lineage: Recovery of Nature's Lost Treasure Since 1970's

    4th International Conference on Nitrification  

    発表年月: 2015年06月

  • Selective Enrichment of Uncultured Ammonia-Oxidizing Bacteria and Archaea and Nitrospira from Freshwater by Continuous Feeding Bioreactors

    4th International Conference on Nitrification  

    発表年月: 2015年06月

  • 腸管炎症制御に関与する常在細菌-TLRsの相互作用

    第19回腸内細菌学会  

    発表年月: 2015年06月

  • Moleculat Mechanism Analysis of Persisters Formation with a Cell Division Marker

    6th Congress of European Microbiologists  

    発表年月: 2015年06月

  • The Identification Method for Cleavage Sequences of MazF Family Endoribonucleases Using Massive Parallel Sequencing

    6th Congress of European Microbiologists  

    発表年月: 2015年06月

  • The interaction between host and commensal bacteria through the farnesoid X receptor

    第88回日本細菌学会総会  

    発表年月: 2015年03月

  • The physiological importance of commensal Enterobacteriaceae populations in the gut homeostasis

    第88回日本細菌学会総会  

    発表年月: 2015年03月

  • 細菌の休止状態に関係する遺伝子発現の網羅的解析

    第88回日本細菌学会総会  

    発表年月: 2015年03月

  • The role of bacterial component in the progression of non-alcohol liver disease

    第88回日本細菌学会総会  

    発表年月: 2015年03月

  • 大腸腫瘍由来オルガノイドに見られる異常形態形成の数理モデリング

    日本物理学会第70回年次大会  

    発表年月: 2015年03月

  • 配向を制御した骨格筋細胞シートの機能評価

    第14回日本再生医療学会総会  

    発表年月: 2015年03月

  • 3次元心筋組織構築に向けた低温培養の影響評価

    第14回日本再生医療学会総会  

    発表年月: 2015年03月

  • HepG2細胞の低酸素領域における酸素消費動態解析

    化学工学会第80年会  

    発表年月: 2015年03月

  • 腸オルガノイド形態成数理モデの構築

    定量生物学の会 第7回年会  

    発表年月: 2015年01月

  • ヒト結腸陰窩細胞動態の三次元数理モデル

    定量生物学の会 第7回年会  

    発表年月: 2015年01月

  • Exploring the intestinal bacteria involved in the regulation of immune-metabolism

    Hindgut Club JAPAN symposium  

    発表年月: 2014年12月

  • 包括固定化アナモックス担体を用いた好気脱窒システムの実証

    日本水処理生物学会第51回大会  

    発表年月: 2014年11月

  • Fabrication of Biomimetic Three-Dimensional Muscle Tissue Construct with Well-Organized Orientation

    7th World Congress on Preventive and Regenerative Medicine  

    発表年月: 2014年11月

  • The Effectiveness of Low Temperature Cultivation (LTC) for Tissue Engineering

    7th World Congress on Preventive and Regenerative Medicine  

    発表年月: 2014年11月

  • Establishment of a novel assay for MPLW515L/K detection and allele burden measurement

    第76回日本血液学会学術集会  

    発表年月: 2014年10月

  • MPL mutation analysis of Ph-negative myeloproliferative neoplasms in Japan

    第76回日本血液学会学術集会  

    発表年月: 2014年10月

  • 比較解析から迫る亜硝酸酸化細菌Nitrospiraの生態学的ニッチ

    環境微生物系学会合同大会2014  

    発表年月: 2014年10月

  • 難培養性アンモニア酸化細菌Nitrosomonas mobilisの分離培養と生理学的性質の解明

    環境微生物系学会合同大会2014  

    発表年月: 2014年10月

  • nxrBを標的としたin situ RCA-FISH法による亜硝酸酸化細菌の探索

    環境微生物系学会合同大会2014  

    発表年月: 2014年10月

  • 腸炎の寛解誘導に関わる腸管内細菌代謝物動態の解析

    平成26年度日本生物工学会大会  

    発表年月: 2014年09月

  • 抗炎症能を有する腸内細菌のスクリーニングとその作用機序の解明

    平成26年度日本生物工学会大会  

    発表年月: 2014年09月

  • アナモックス反応を用いた好気脱窒システムの検証

    第17回日本水環境学会シンポジウム  

    発表年月: 2014年09月

  • Selective Inoculation of Microcolonies Materializes Cultivation and Isolation of Previously Uncultured Nitrifying Bacteria

    15th International Symposium on Microbial Ecology  

    発表年月: 2014年08月

  • Detection of nxrB Genes by in situ RCA-FISH to Identify Unrecognized Nitrite-Oxidizing Microorganisms in Environments

    15th International Symposium on Microbial Ecology  

    発表年月: 2014年08月

  • Selective Enrichment of Uncultured Ammonia-Oxidizing Bacteria and Archaea and Nitrite-0xidizing Bacteria from Freshwater

    15th International Symposium on Microbial Ecology  

    発表年月: 2014年08月

  • Selective Enrichment of Ammonia-Oxidizing Archaea and Bacteria from Freshwater

    Water Environment and Technology Conference 2014  

    発表年月: 2014年06月

  • The MPLW515L/K Simultaneous Detection/Quantitation Method That Is Tractable to the Massivly Parallel Sequencing

    19th Congress of the European Hematology Association  

    発表年月: 2014年06月

  • 腸内細菌代謝産物を介した大腸上皮細胞の炎症応答抑制機構の探索

    第18回腸内細菌学会  

    発表年月: 2014年06月

  • 腸内細菌による腸管上皮バリア機能の強化・修復

    第18回腸内細菌学会  

    発表年月: 2014年06月

  • RNA干渉酵素を用いたRNA切断技術の開発

    日本農芸化学会2013年度大会  

    発表年月: 2014年03月

  • 細菌分裂活性マーカーを用いた休止細菌分子機構の解析

    第87回日本細菌学会総会  

    発表年月: 2014年03月

  • バイオフィルム中で薬剤寛容性を示す休止細菌の時空間ダイナミクス解析

    第87回日本細菌学会総会  

    発表年月: 2014年03月

  • 微小ガラス電極を用いたヒト心筋細胞の酸素消費動態解析

    化学工学会第79年会  

    発表年月: 2014年03月

  • 淡水環境堆積物からのAnammox細菌の低温集積培養

    第48回日本水環境学会年会  

    発表年月: 2014年03月

  • 排水処理槽内から単離された2種類のNitrospiraの比較解析

    第48回日本水環境学会年会  

    発表年月: 2014年03月

  • 包括固定化アナモックス担体のメタノール耐性と馴養

    第48回日本水環境学会年会  

    発表年月: 2014年03月

  • 微小ガラス電極を用いた酸素計測による心筋細胞の動態評価

    第13回日本再生医療学会総会  

    発表年月: 2014年03月

  • 効率的な酸素供給を実現する新規培養手法の構築

    第13回日本再生医療学会総会  

    発表年月: 2014年03月

  • The Regulation of the Intestinal Epithelial Tight Junction Protein by Bifidobacterium bifidum

    第42回日本免疫学会学術集会  

    発表年月: 2013年12月

  • The Role of Gut Microbiota in the Progression of Non-Alcohol Fatty Liver Disease

    第42回日本免疫学会学術集会  

    発表年月: 2013年12月

  • 腸管上皮バリア機能の強化・修復を担う腸内細菌の探索

    Hindgut Club Japan 2013  

    発表年月: 2013年12月

  • 亜硝酸酸化細菌Nitrospiraを標的とした新規分離培養手法と他の難培養性微生物への適用

    第29回日本微生物生態学会  

    発表年月: 2013年11月

  • 低濃度アンモニアの連続供給による難培養性硝化微生物の選択的集積培養

    第29回日本微生物生態学会  

    発表年月: 2013年11月

  • 機能遺伝子nxrBに基づく新規な亜硝酸酸化細菌の探索

    第29回日本微生物生態学会  

    発表年月: 2013年11月

  • RNA干渉酵素の酵素活性評価手法の構築とその利用

    第29回日本微生物生態学会  

    発表年月: 2013年11月

  • 環境中に潜在するAnammox細菌の集積培養と群集構造解析

    第29回日本微生物生態学会  

    発表年月: 2013年11月

  • 「個」と「集団」で生きる微生物たちを分ける —生育形態と難培養性との関係に迫る—

    第29回日本微生物生態学会  

    発表年月: 2013年11月

  • マウス結腸陰窩細胞動態の三次元モデルの構築

    定量生物学の会 第6回年会  

    発表年月: 2013年11月

  • Establishment of a Newly Developed Culture Method Providing Efficient Oxygen Supply to Biological Systems

    Functional Analysis and Screening Technologies Conference  

    発表年月: 2013年10月

  • A highly sensitive and reliable JAK2V617F detection method for the diagnostics of MPN

    第75回日本血液学会学術集会  

    発表年月: 2013年10月

  • Identification and biochemical analysis of cholesterol sulfate and halisulfate 3 as novel hepatitis C virus NS3 helicase inhibitors from marine natural products

    HCV meeting 2013  

    発表年月: 2013年10月

  • 長波長蛍光標識RNAプローブを用いたC型肝炎ウイルスNS3 helicaseの新規な活性測定手法

    平成25年度日本生物工学会大会  

    発表年月: 2013年09月

  • In situ Identification of Persisters by Visualizing Z-Ring Formation

    Euro Biofilms 2013  

    発表年月: 2013年09月

  • Molecular Analysis of Enrichment Cultures of Freshwater Anammox Bacteria

    3rd International Conference on Nitrification  

    発表年月: 2013年09月

  • Comparative Physiological Analysis of Nitrospira Strains Isolated from a Wastewater Treatment Plant

    3rd International Conference on Nitrification  

    発表年月: 2013年09月

  • High-Rate Nitrification of Electronic Industry Wastewater by Using Nitrifying Granules

    3rd International Conference on Nitrification  

    発表年月: 2013年09月

  • An Innovative Cultivation and Isolation Strategy for Uncultured Nitrifying Bacteria

    3rd International Conference on Nitrification  

    発表年月: 2013年09月

  • 局所酸素濃度計測による心筋細胞の機能評価

    第17回酸素ダイナミクス研究会  

    発表年月: 2013年08月

  • Applicability of a Sequencing Batch Membrane Biofilm Reactor for Simultaneous Nitrogen and Phosphorus Removal from Low C/N Ratio Wastewater

    Water Environment and Technology Conference 2013  

    発表年月: 2013年06月

  • 腸内細菌代謝産物を介した大腸上皮細胞の炎症応答抑制

    第17回腸内細菌学会  

    発表年月: 2013年06月

  • 海綿Amphimedon sp.抽出画分のHCVゲノム複製阻害効果とその作用機序

    第23回抗ウイルス療法研究会総会  

    発表年月: 2013年06月

  • 海洋生物抽出物より取得したcholesterol sulfateおよびhalisulfate 3によるC型肝炎ウイルスNS3 helicase阻害作用

    第23回抗ウイルス療法研究会総会  

    発表年月: 2013年06月

  • The Interaction between Commensal Bacteria and Innate Immune Receptors for Modulating the Intestinal Inflammatory Response

    Cell Symposia: Microbiome and Host Health  

    発表年月: 2013年05月

  • 灌流培養バイオリアクタを用いた血管網付きヒト心筋組織の構築

    第12回日本再生医療学会総会  

    発表年月: 2013年03月

  • ラットおよびヒトiPS細胞由来心筋細胞の局所酸素濃度に応じた代謝動態

    第12回日本再生医療学会総会  

    発表年月: 2013年03月

  • 心臓を構成する各種細胞の酸素消費速度の測定

    第12回日本再生医療学会総会  

    発表年月: 2013年03月

  • An Innovative Cultivation and Isolation Strategy for Uncultured Nitrifying Bacteria

    CER International workshop on Biogeochemical cycling and Microbial Ecology for Young Scientists  

    発表年月: 2013年03月

  • 細菌の分裂活性に基づいたdormant persister の新規マーカーの開発

    第86回日本細菌学会総会  

    発表年月: 2013年03月

  • Pseudomonas aeruginosa PAO1のバイオフィルム形成における休止細菌の時空間ダイナミクスの解析

    第86回日本細菌学会総会  

    発表年月: 2013年03月

  • 淡水環境に生息する難培養性硝化細菌の新規分離培養手法の開発

    第47回日本水環境学会年会  

    発表年月: 2013年03月

  • 包括固定化担体を用いた好気脱窒システムの安定性評価

    第47回日本水環境学会年会  

    発表年月: 2013年03月

  • 新規分離培養手法のアナモックス細菌への適用

    第47回日本水環境学会年会  

    発表年月: 2013年03月

  • 腸炎の病態形成に関わる腸内環境因子の探索

    第18回Hindgut Club Japanシンポジウム  

    発表年月: 2012年12月

  • 腸管炎症制御に関わる細菌−自然免疫細胞の相互作用の解明

    第18回Hindgut Club Japanシンポジウム  

    発表年月: 2012年12月

  • Repairing of TNF-α Induced Intestinal Epithelial TJ Dysfunction by Bifidobacterium bifidum Isolated from Normal Individual

    第41回日本免疫学会学術集会  

    発表年月: 2012年12月

  • A Feasibility Study on Monitoring the State of Culturing Myocardial Tissues by the Glucose Metabolism Measurement

    TERMIS-NA 2011  

    発表年月: 2012年12月

  • 結腸上皮細胞アポトーシス動態が細胞種ごとに異なるという予測の検証

    定量生物学の会 第5回年会  

    発表年月: 2012年11月

  • 微生物情報伝達物質を分解するろ過膜よるバイオフィルムの抑制

    平成24年度日本生物工学会大会  

    発表年月: 2012年10月

  • 海洋生物抽出物より取得した複数種の硫酸化合物によるC型肝炎ウイルスNS3 helicase阻害作用

    平成24年度日本生物工学会大会  

    発表年月: 2012年10月

  • 心筋細胞シートにおけるエネルギー代謝

    第16回酸素ダイナミクス研究会  

    発表年月: 2012年09月

  • 単層培養系における局所酸素濃度の測定

    第16回酸素ダイナミクス研究会  

    発表年月: 2012年09月

  • 培養できない微生物を培養するための新規技術開発

    第28回日本微生物生態学会  

    発表年月: 2012年09月

  • mRNA interferaseを用いたRNAの配列特異的な切断技術の開発

    第28回日本微生物生態学会  

    発表年月: 2012年09月

  • システム論的アプローチによる環境浄化微生物コミュニティーデザイン

    第28回日本微生物生態学会  

    発表年月: 2012年09月

  • バイオインターフェイスの改質による水処理におけるバイオフィルム制御:バイオフィルムリアクターの

    第28回日本微生物生態学会  

    発表年月: 2012年09月

  • 難培養性Nitrospiraの単離が排水処理プロセスでの亜硝酸酸化細菌の生理学的性質を明らかにする

    第28回日本微生物生態学会  

    発表年月: 2012年09月

  • Measuring Energy Metabolism of Cell Sheets Used for Tissue Engineering

    2012 International Symposium of Materials on Regenerative Medicine  

    発表年月: 2012年09月

  • Metabolic Change of Cultured Cell Sheets Depending on Oxygen Supply

    TERMIS-WC 2012  

    発表年月: 2012年09月

  • Vascularized Tissue Fabrication from Human Cells Using in vitro Bioreactor

    TERMIS-WC 2012  

    発表年月: 2012年09月

  • 蛍光発生プローブによるスプライシング反応の解析

    第4回日本RNAi研究会  

    発表年月: 2012年08月

  • Novel Method for Cultivation of Uncultured Nitrifying Bacteria

    14th International Symposium on Microbial Ecology  

    発表年月: 2012年08月

  • Selective Cultivation of Nitrifying Bacteria Present in Drinking Water Treatment Plants

    14th International Symposium on Microbial Ecology  

    発表年月: 2012年08月

  • Comparative Physiological Analysis of Previously Uncultured Nitrospira Strains Isolated

    14th International Symposium on Microbial Ecology  

    発表年月: 2012年08月

  • Host-microbes Interplay Involved in the Resolution of Intestinal Inflammation

    14th International Symposium on Microbial Ecology  

    発表年月: 2012年08月

  • Computational Modeling of Microbial Granulation Processes for Wastewater Treatment

    14th International Symposium on Microbial Ecology  

    発表年月: 2012年08月

  • 培地・酸素供給の変化に応じた細胞シートの代謝変動特性

    第11回日本再生医療学会総会  

    発表年月: 2012年06月

  • 生体外における血管網付ヒト三次元組織の構築

    第11回日本再生医療学会総会  

    発表年月: 2012年06月

  • 大腸上皮細胞を用いた炎症応答抑制に関わる腸内細菌の探索

    第16回腸内細菌学会  

    発表年月: 2012年06月

  • DSS腸炎マウスの病態形成過程における腸内細菌由来TLRs刺激能の動態

    第16回腸内細菌学会  

    発表年月: 2012年06月

  • 細胞シート積層による三次元心筋組織構築過程における代謝評価

    日本組織培養学会第85回大会  

    発表年月: 2012年05月

  • 再生医療に用いる細胞シートのエネルギー代謝

    日本組織培養学会第85回大会  

    発表年月: 2012年05月

  • Clinical Relevance of JAK2 V617F Somatic Point Mutation in Japanese Myeloproliferative Neoplasm Patients

    3rd JSH International Symposium 2012  

    発表年月: 2012年05月

  • Inhibition of Hepatitis C Virus Replication and Viral Helicase by Ethyl Acetate Extract of the Marine Feather Star Alloeocomatella polycladia

    25th International Conference on Antiviral Research  

    発表年月: 2012年04月

  • in vivo培養システムの開発と口腔内に生息する未培養性微生物の取得・解明

    第12回化学工学会学生発表会 東京大会  

    発表年月: 2012年03月

  • 排水処理槽内に生息する難培養性亜硝酸酸化細菌Nitrospiraの分離培養

    第12回化学工学会学生発表会 東京大会  

    発表年月: 2012年03月

  • 大腸上皮組織中における細胞増殖—アポトーシスバランスの数理モデル構築

    第12回化学工学会学生発表会 東京大会  

    発表年月: 2012年03月

  • アナモックス反応による好気脱窒システムの性能評価

    第46回日本水環境学会年会  

    発表年月: 2012年03月

  • ゼオライト成形体と水生植物を活用した里川再生技術の実河川への応用

    第46回日本水環境学会年会  

    発表年月: 2012年03月

  • 微生物情報伝達を遮断する機能性ろ過膜における膜の目詰まり防止の試み

    第46回日本水環境学会年会  

    発表年月: 2012年03月

  • 単層細胞シートの代謝評価と酸素供給の影響

    化学工学会第77年会  

    発表年月: 2012年03月

  • バイオフィルム由来の目詰まりを抑制する酵素固定化型ろ過膜の開発

    化学工学会第77年会  

    発表年月: 2012年03月

  • 新規蛍光発生化合物を用いた細胞内遺伝子検出プローブの改良と評価

    日本薬学会第132年会  

    発表年月: 2012年03月

  • 生体組織維持におけるアポトーシスの役割:数理モデルによる定量解析

    定量生物学の会 第4回年会  

    発表年月: 2012年01月

  • Fluorogenic Probe for Detection of mRNA and Intron Lariat RNA

    第38回国際核酸化学シンポジウム  

    発表年月: 2011年11月

  • Induction of Mucosal Immune Responses via M cells within Nasal-Associated Lymphoid Tissue

    第40回日本免疫学会学術集会  

    発表年月: 2011年11月

  • Nitrogen Treatment by Direct Purification Technology Using Molded Zeolite and Aquatic Plants in an Actual Stream

    The 4th IWA-ASPIRE Conference  

    発表年月: 2011年10月

  • 腸内細菌叢が大腸炎の病態に与える影響解析

    第27回日本微生物生態学会  

    発表年月: 2011年10月

  • 浄水処理プロセス由来の新規硝化細菌の分離培養

    第27回日本微生物生態学会  

    発表年月: 2011年10月

  • 亜硝酸酸化細菌Nitrospiraの新規分離培養手法とその実証

    第27回日本微生物生態学会  

    発表年月: 2011年10月

  • 新生仔ラット心筋細胞シートにおける内皮細胞の動態イメージング

    第20回バイオイメージング学会学術集会  

    発表年月: 2011年09月

  • Characterization of Colonic Microflora and Innate Immune-Stimulatory Activity during Colitis Progression

    IUMS2011  

    発表年月: 2011年09月

  • In vitro Screening of Prospective Bacteria Modulating the Epithelial Inflammatory Response

    IUMS2011  

    発表年月: 2011年09月

  • Microbial Population Dynamics during the Formation of Nitrifying Granules and Protein Putatively Relevant for Granulation

    IUMS2011  

    発表年月: 2011年09月

  • Quantitative Detection of Cryptosporidium Oocyst in Water Source by Alternatively Binding Probe Competitive Polymerase Chain Reaction (ABC-PCR)

    16th International Symposium on Health-Related Water Microbiology  

    発表年月: 2011年09月

  • 水質浄化ゼオライト成形体の導入による魚類の生息・産卵場所の創造

    日本陸水学会第76回大会  

    発表年月: 2011年09月

  • ゼオライト成形体と水生植物を活用した生態工学技術による小河川の再生

    日本陸水学会第76回大会  

    発表年月: 2011年09月

  • 還元反応を引き金とした蛍光発生核酸プローブによるスプライシング反応産物の検出

    日本分析化学会第60年会  

    発表年月: 2011年09月

  • 腸炎の病態形成に寄与する腸内環境因子の探索

    平成23年度日本生物工学会大会  

    発表年月: 2011年09月

  • 海洋生物抽出物より取得したcholesterol sulfateによるC型肝炎ウイルスNS3 helicase阻害作用

    平成23年度日本生物工学会大会  

    発表年月: 2011年09月

  • In Vitro Construction of Human Vascular Bed for 3-D Tissue Fabrication

    TERMIS AP  

    発表年月: 2011年08月

  • マルチオーミクス解析による腸内環境分子間ネットワークの構築

    第15回腸内細菌学会  

    発表年月: 2011年06月

  • High-Throughput in situ Cultivation for Accessing Uncultivable Environmental Microorganisms

    Biochemical and Molecular Engineering XVII  

    発表年月: 2011年06月

  • Development of a Computational Model for the Growth Process of Microbial Granules

    Biochemical and Molecular Engineering XVII  

    発表年月: 2011年06月

  • 三胚葉由来組織に共通する成体幹細胞の探索

    第10回日本再生医療学会総会  

    発表年月: 2011年03月

  • アナモックス反応を利用した好気脱窒システムにおける窒素除去特性

    第45回日本水環境学会年会  

    発表年月: 2011年03月

  • ゼオライト成形体と水生植物を活用した里川再生技術の実河川における検討

    第45回日本水環境学会年会  

    発表年月: 2011年03月

  • 畜産排水除去を志向した飼料イネ水田におけるPlanctomycetes 門の生態構造解析

    第45回日本水環境学会年会  

    発表年月: 2011年03月

  • 微生物グラニュールによる窒素・リン同時除去プロセスの解明:実験と数理モデリング

    化学工学会第76年会  

    発表年月: 2011年03月

  • 還元反応を引き金とした蛍光発生プローブによるスプライシング反応産物の検出

    日本薬学会第131年会  

    発表年月: 2011年03月

  • Alternately Binding Quenching Probe Competitive PCR: Simple, Sensitive, and Cost-Effective JAK2 Allele Burden Quantification Method

    52nd ASH Annual Meeting and Exposition  

    発表年月: 2010年12月

  • The Potential of Stem Cells in Adult Tissues Representative of the Three Germ Layers

    TERMIS NA  

    発表年月: 2010年12月

  • 沖縄産ウミシダ(Alloeocomatella polycladia)抽出物の抗HCV NS3 helicase阻害活性によるHCV増殖抑制効果

    第58回日本ウイルス学会  

    発表年月: 2010年11月

  • 担体利用1槽型アナモックスシステムの基礎検討

    日本水処理生物学会第47回大会  

    発表年月: 2010年11月

  • Growth Characteristics of Uncultured Nitrite-Oxidizing Nitrospira

    第25回日本微生物生態学会  

    発表年月: 2010年11月

  • Development of in vivo cultivation method targeting human oral microbes

    第25回日本微生物生態学会  

    発表年月: 2010年11月

  • High-Throughput in situ Cultivation - Accessing to Uncultivable Environmental Microorganisms

    第25回日本微生物生態学会  

    発表年月: 2010年11月

  • Alternately binding probe competitive (ABC) helicase-dependent amplification (HDA) 法による簡便な遺伝子定量技術の開発

    平成22年度日本生物工学会大会  

    発表年月: 2010年10月

  • 好気グラニュールを用いた高速硝化処理

    第13回日本水環境学会シンポジウム  

    発表年月: 2010年09月

  • High Throughput in situ Cultivation of Environmental Microorganisms

    13th International Symposium on Microbial Ecology  

    発表年月: 2010年08月

  • Selective and Highly Efficient Enrichment of Uncultured Nitrospira

    13th International Symposium on Microbial Ecology  

    発表年月: 2010年08月

  • 有機化学反応を用いた蛍光発生プローブによる核酸分子の検出

    日本化学会第4回関東支部大会  

    発表年月: 2010年08月

  • 有機化学反応を用いた蛍光発生プローブを用いたペプチド検出

    日本化学会第4回関東支部大会  

    発表年月: 2010年08月

  • Formation of Aerobic Granular Sludge in a Continuous Flow Reactor - Control Strategy for Selection of Well-Settling Granular Sludge-

    Water Environment and Technology Conference 2010  

    発表年月: 2010年06月

  • Nitrogen Removal Performance of Heterotrophic Denitrifying Bacteria Entrapped in PEG Gel Carriers

    Water Environment and Technology Conference 2010  

    発表年月: 2010年06月

  • Enhancing Nitrogen and Phosphorus Removal in an Anaerobic/Oxic/Anoxic Sequencing Batch Reactor: The Dependence of the Amount of External Carbon

    Water Environment and Technology Conference 2010  

    発表年月: 2010年06月

  • Significance of Reactor Type for High-Rate Nitrification Using Aerobic Granular Sludge

    Water Environment and Technology Conference 2010  

    発表年月: 2010年06月

  • 還元を引き金とする蛍光発生システムによる遺伝子検出

    日本ケミカルバイオロジー学会第5回年会  

    発表年月: 2010年05月

  • Monitoring of metabolic dynamics in microbial ecosystems using a combination of DNA fingerprinting and metabolome analysis based on stable isotope labeling

    2nd TNO Beneficial Microbes Conference  

    発表年月: 2010年03月

  • Evaluation of gut environmental dynamics based on gene expression profiling

    2nd TNO Beneficial Microbes Conference  

    発表年月: 2010年03月

  • 難培養性微生物の新規分離培養手法-in vivo 培養-

    第12回化学工学会学生発表会 東京大会  

    発表年月: 2010年03月

  • DSS腸炎モデルマウスを用いた腸管炎症時の腸内細菌叢解析

    第12回化学工学会学生発表会 東京大会  

    発表年月: 2010年03月

  • 有機化学反応を引き金とした核酸分子検出技術の開発

    第12回化学工学会学生発表会 東京大会  

    発表年月: 2010年03月

  • 新規遺伝子定量手法ABC-PCR法を用いた水中の病原微生物の定量

    第44回日本水環境学会年会  

    発表年月: 2010年03月

  • 好気性グラニュールにおける微生物生態構造解析とその制御

    第44回日本水環境学会年会  

    発表年月: 2010年03月

  • 好気性ク?ラニュールにおける微生物生態構造:数理モテ?ル構築とシミュレーション

    第44回日本水環境学会年会  

    発表年月: 2010年03月

  • ゼオライト成形体と水生植物を活用した里川再生技術の実河川における検討

    第44回日本水環境学会年会  

    発表年月: 2010年03月

  • 半導体工場排水を対象としたグラニュールによる高速硝化パイロットスケール試験

    第44回日本水環境学会年会  

    発表年月: 2010年03月

  • アナモックス反応に及ぼすDOの影響

    第44回日本水環境学会年会  

    発表年月: 2010年03月

  • 角膜内皮細胞特異的細胞表面マーカーの同定

    第9回日本再生医療学会総会  

    発表年月: 2010年03月

  • 皮下移植後の組織再構築因子の探索

    第9回日本再生医療学会総会  

    発表年月: 2010年03月

  • 異なる表面電位を有する材料表面への微生物の初期付着とバイオフィルム構造の関係解明

    化学工学会第75年会  

    発表年月: 2010年03月

  • ヒト大腸陰窩における分裂細胞空間配置パターンのダイナミクス

    日本物理学会第65回年次大会  

    発表年月: 2010年03月

  • 還元反応を引き金とする蛍光発生システムを用いた核酸検出

    日本化学会第90春季年会  

    発表年月: 2010年03月

  • 膜透過能を有する修飾ダンベル型RNAによるRNA干渉法の開発

    日本化学会第90春季年会  

    発表年月: 2010年03月

  • 環境微生物の選択的分離技術の開発-Microbial Cell Chromatography-

    日本農芸化学会2010年度大会  

    発表年月: 2010年03月

  • ハイスループットinsitu分離培養法‐難培養性微生物への効率的アクセス‐

    日本農芸化学会2010年度大会  

    発表年月: 2010年03月

  • 発現遺伝子情報に基づく腸内環境評価系の構築

    日本農芸化学会2010年度大会  

    発表年月: 2010年03月

  • 安定同位体標識技術を活用した複合微生物系における新規代謝動態解析法

    日本農芸化学会2010年度大会  

    発表年月: 2010年03月

  • 腸陰窩における細胞配置のタ?イナミクス

    定量生物学の会 第2回年会  

    発表年月: 2010年01月

  • Universal quenching probe system: flexible, specific, and cost-effective real-time polymerase chain reaction method

    第32回日本分子生物学会年会  

    発表年月: 2009年12月

  • Construction of Gut Environment Assessment System Based on Multiple Omics Approach

    第32回日本分子生物学会年会  

    発表年月: 2009年12月

  • Photoactivation of Caged Fluorescent Oligodeoxynucleotide in Cell

    Joint Symposium of 5th Annual Meeting of Oligonucleotide Therapeutics Society and the 19th Antisense Symposium  

    発表年月: 2009年11月

  • 修飾ダンベル型RNAによるRNA干渉法の開発

    第28回メディシナルケミストリーシンポジウム  

    発表年月: 2009年11月

  • 好気グラニュールを用いた電子産業排水の高速硝化処理

    日本水処理生物学会第46回大会  

    発表年月: 2009年11月

  • High Throughput in situ Cultivation as a New Method for Cultivation of Uncultivable Environmental Microorganisms

    Asia Pacific Biochemical Engineering Conference (APBioChEC'09)  

    発表年月: 2009年11月

  • 繊維摂取に伴うマウス腸内フローラの変動と物流システム評価

    第25回日本微生物生態学会  

    発表年月: 2009年11月

  • 難培養性亜硝酸酸化細菌Nitrospiraの分離培養

    第25回日本微生物生態学会  

    発表年月: 2009年11月

  • High Rate Nitrification Using Aerobic Granular Sludge

    6th Netherlands-Japan Workshop on Water Technology  

    発表年月: 2009年10月

  • 海洋生物抽出液ライブラリーからのC型肝炎ウイルスNS3 helicase活性阻害物質の探索

    第57回日本ウイルス学会  

    発表年月: 2009年10月

  • Significance of Reactor Type for High-Rate Nitrification Using Aerobic Granular Sludge

    IWA 2nd Specialized Conference on Nutrient Management in Wastewater Treatment Process  

    発表年月: 2009年09月

  • Inflammation Analyses after Subcutaneous Transplantation of Cell Sheets for a Novel Tissue Engineering Method

    TERMIS 2nd World Congress  

    発表年月: 2009年09月

  • Subcutaneous Transplantation of Oral Muscosal Epithelial Cell Sheets Fabricated on Temperature-Responsive Culture Dishes

    TERMIS 2nd World Congress  

    発表年月: 2009年09月

  • 新規等温遺伝子定量手法Alternately binding probe competitive helicase-dependent amplification (ABC-HDA)法の開発

    平成21年度日本生物工学会大会  

    発表年月: 2009年09月

  • RNA情報を釣り針とする微生物生細胞の分離・濃縮技術の開発

    平成21年度日本生物工学会大会  

    発表年月: 2009年09月

  • 蛍光消光現象を利用したC型肝炎ウイルス由来ヘリカーゼ活性阻害剤の探索

    平成21年度日本生物工学会大会  

    発表年月: 2009年09月

  • ダンベル型ナノサークルRNAによるRNA干渉法

    平成21年度日本生物工学会大会  

    発表年月: 2009年09月

  • Alternately binding probe competitive (ABC)-PCR法を用いた土壌サンプルからのDNA抽出効率算出法

    平成21年度日本生物工学会大会  

    発表年月: 2009年09月

  • Cell proliferation and differentiation in the intestinal crypt using an individual-based model(個体ベースモデルを用いた腸管陰窩における細胞増殖分化のシミュレーション)

    第19回日本数理生物学会  

    発表年月: 2009年09月

  • 塩基配列に基づいた遺伝子探索のための選択的DNA増幅手法の開発

    日本化学会第3回関東支部大会  

    発表年月: 2009年09月

  • Reduction-Triggered Fluorescence Amplification Probe for the Detection of Intracellular RNAs

    42nd IUPAC Congress  

    発表年月: 2009年08月

  • 化学反応をトリガーとする蛍光発生分子を用いる生細胞内RNA検出

    第38回医用高分子シンポジウム  

    発表年月: 2009年07月

  • 修飾ダンベル型RNAによるRNA干渉法の開発

    第25回DDS学会学術集会  

    発表年月: 2009年07月

  • 複合オミックス解析による腸内環境評価系の構築

    第13回腸内細菌学会  

    発表年月: 2009年06月

  • New Methodologies for Isolation and Cultivation of Uncultivable Microorganisms in Wastewater Treatment Processes

    Microbial Population Dynamics in Biological Wastewater Treatment (ASPD5)  

    発表年月: 2009年05月

  • Microscopic and Macroscopic Models for Aerobic Granular Sludge Processes

    Microbial Population Dynamics in Biological Wastewater Treatment (ASPD5)  

    発表年月: 2009年05月

  • C型肝炎ウイルス(HCV)由来NS3ヘリケース活性阻害剤の探索

    日本薬学会第129年会  

    発表年月: 2009年03月

  • 膜透過性と細胞内安定性の向上を目指したダンベル型RNAの改良合成

    日本化学会第89春季年会  

    発表年月: 2009年03月

  • 細胞内遺伝子検出プローブのための新規蛍光発生型化合物の合成

    日本化学会第89春季年会  

    発表年月: 2009年03月

  • 生細胞内チオール検出に用いる新規蛍光化合物の合成

    日本化学会第89春季年会  

    発表年月: 2009年03月

  • 化学反応プローブを用いた遺伝子情報に基づく生細胞選別技術の開発

    日本化学会第89春季年会  

    発表年月: 2009年03月

  • 腸管上皮における細胞増殖・分化過程の数理モデリング

    日本物理学会第64回年次大会  

    発表年月: 2009年03月

  • 耕地土壌におけるキチナーゼの多様性および環境因子との関連性

    日本農芸化学会2009年度大会  

    発表年月: 2009年03月

  • 難培養性微生物のハイスループットin situ 分離培養

    日本農芸化学会2009年度大会  

    発表年月: 2009年03月

  • rRNAを標的とした化学反応プローブを用いる微生物生細胞のセレクション

    日本農芸化学会2009年度大会  

    発表年月: 2009年03月

  • RT-LAMP法を用いた白血病マーカーWT1 mRNAの迅速・簡便定量技術の開発

    化学工学会第74年会  

    発表年月: 2009年03月

  • マグネティックビーズを用いたアフィニティキャピラリー電気泳動法による16S rRNAの検出

    化学工学会第74年会  

    発表年月: 2009年03月

  • 半回分式メンブレンバイオフィルムリアクタによる窒素・リン同時除去:低C/N比排水への適用

    第43回日本水環境学会年会  

    発表年月: 2009年03月

  • ポリリン酸蓄積細菌の新規分離培養法

    第43回日本水環境学会年会  

    発表年月: 2009年03月

  • 好気性グラニュールを用いた窒素・リン同時除去プロセスの数理モデリングとシミュレーション

    第43回日本水環境学会年会  

    発表年月: 2009年03月

  • 好気性グラニュールを種汚泥として用いた硝化リアクターの迅速スタートアップに関する研究

    第43回日本水環境学会年会  

    発表年月: 2009年03月

  • 難培養性亜硝酸酸化細菌Nitrospiraの新規分離培養法

    第43回日本水環境学会年会  

    発表年月: 2009年03月

  • 硝化グラニュール形成に関与する細菌群の単離および凝集機構解明

    第43回日本水環境学会年会  

    発表年月: 2009年03月

  • 硝化グラニュールの形成に関わる操作条件の解明

    第43回日本水環境学会年会  

    発表年月: 2009年03月

  • 硝化グラニュールによる電子産業排水の高速硝化処理

    第43回日本水環境学会年会  

    発表年月: 2009年03月

  • Pre-amplified inverse PCRを用いた環境試料からの新規エステラーゼ遺伝子の取得

    第3回日本ゲノム微生物学会年会  

    発表年月: 2009年03月

  • 結腸陰窩における細胞増殖分化の時空間ダイナミクス

    第5回「生物数学の理論とその応用」  

    発表年月: 2009年01月

  • バクテリアによる自己造粒体(グラニュール)形成過程のマルチスケールモデリング

    定量生物学の会 第1回年会  

    発表年月: 2009年01月

  • 結腸陰窩における細胞増殖分化のシミュレータ開発及び実験データとの定量比較

    定量生物学の会 第1回年会  

    発表年月: 2009年01月

  • 粘膜関連リンパ組織におけるM細胞関連タンパク質の発現局在解析 Comprehensive analysis of the expression of M-cell-associated proteins among mucosa-associated lymphoid tissue

    第38回日本免疫学会学術集会  

    発表年月: 2008年12月

  • 環境微生物の選択的濃縮技術の開発 -Microbial Cell Chromatography-

    第24回日本微生物生態学会  

    発表年月: 2008年11月

  • 生育環境を模擬可能な新規ハイスループット分離培養手法

    第24回日本微生物生態学会  

    発表年月: 2008年11月

  • 初期形成段階における硝化細菌グラニュールの微生物生態構造解析

    第24回日本微生物生態学会  

    発表年月: 2008年11月

  • 遺伝子情報に基づいた微生物生細胞の特異的分離技術の開発

    第24回日本微生物生態学会  

    発表年月: 2008年11月

  • 好気グラニュールによる高速硝化処理の諸因子の検討

    日本水処理生物学会第45回大会  

    発表年月: 2008年11月

  • 標的遺伝子上で赤色蛍光を発する新規蛍光プローブの合成

    第18回アンチセンスシンポジウム  

    発表年月: 2008年11月

  • ダンベル型ナノサークルRNAによるRNA干渉法

    第18回アンチセンスシンポジウム  

    発表年月: 2008年11月

  • Reduction-Triggered Fluorescence Probe Amplifying Nucleic Acids Signal for the Detection of Intracellular RNAs

    14th Symposium of Young Asia Biochemical Engineers Community  

    発表年月: 2008年10月

  • Systems microbial ecology to understand mechanisms of nitrifying granuleformation

    14th Symposium of Young Asia Biochemical Engineers Community  

    発表年月: 2008年10月

  • Microbial Population Dynamics and Community Structure in Nitrifying Granules Analyzed by Experimental Approach and Two-Dimensional Biofilm Model

    Biofilm III  

    発表年月: 2008年10月

  • High-throughput Screening Assay for Hepatitis C Virus Helicase Inhibitors Using Fluorescence-Quenching Phenomenon

    Japan-China Medical Workshop on Drug Discoveries and Therapeutics 2008  

    発表年月: 2008年09月

  • Fluorogenic Probe Triggered by Reduction for Nucleic Acids Sensing

    35th International Symposium on Nucleic Acids Chemistry  

    発表年月: 2008年09月

  • C型肝炎ウイルス由来ヘリケース活性測定法の開発及び活性阻害剤の探索

    化学工学会第40回秋季大会  

    発表年月: 2008年09月

  • 化学反応を引き金とする蛍光発生分子による細胞内RNA検出

    化学工学会第40回秋季大会  

    発表年月: 2008年09月

  • 核酸鋳型反応を用いた遺伝子検出

    第57回高分子討論会  

    発表年月: 2008年09月

  • 環境再生のための分散型高度処理システムのあり方

    第11回日本水環境学会シンポジウム  

    発表年月: 2008年09月

  • Alternately Binding Probe Competitive Polymerase Chain Reaction for Quantification of the gene Encoding Ammonia Monooxygenase

    12th International Symposium on Microbial Ecology  

    発表年月: 2008年08月

  • Characterization of Active Denitrifying Bacteria by 15N-DNA-Stable Isotope Probing

    12th International Symposium on Microbial Ecology  

    発表年月: 2008年08月

  • Quantification of the Genus Dehalococcoides Using Alternately Binding Probe Competitive PCR (ABC-PCR)

    12th International Symposium on Microbial Ecology  

    発表年月: 2008年08月

  • Systems Microbial Ecology to Understand Microbial Community of Nitrifying Granules

    12th International Symposium on Microbial Ecology  

    発表年月: 2008年08月

  • Sequence-Based Approach to Isolate Novel Lipases from Environmental DNA Using pre-Amplified Inverse PCR

    12th International Symposium on Microbial Ecology  

    発表年月: 2008年08月

  • Cultivation of Uncultured Nitrite-Oxidizing Bacteria

    12th International Symposium on Microbial Ecology  

    発表年月: 2008年08月

  • Microbial Cell Chromatography (MCC) as a New Tool for Concentration of Specific Microbial Cell from Environment

    12th International Symposium on Microbial Ecology  

    発表年月: 2008年08月

  • New Cutivation Method for Microorganisms Requiring Environment Simulated Conditions

    12th International Symposium on Microbial Ecology  

    発表年月: 2008年08月

  • アフィニティーキャヒ?ラリー電気泳動法を用いた特定rRNAの連続的定量手法の開発

    平成20年度日本生物工学会大会  

    発表年月: 2008年08月

  • 蛍光を利用した新規ヘリケース活性測定手法の開発

    平成20年度日本生物工学会大会  

    発表年月: 2008年08月

  • Reverse transcription loop-mediated isothermal amplification (RT-LAMP)法を用いた白血病マーカーWT1 mRNAの迅速・簡便定量技術の開発

    平成20年度日本生物工学会大会  

    発表年月: 2008年08月

  • 蛍光消光現象を利用したC型肝炎ウイルス由来ヘリケース活性阻害剤の探索

    平成20年度日本生物工学会大会  

    発表年月: 2008年08月

  • 微生物叢-代謝物群相関解析(DGGE-NMR)法による腸内環境変動の評価法構築

    平成20年度日本生物工学会大会  

    発表年月: 2008年08月

  • ABC-PCR法を用いたDehalococcoides属細菌の定量

    平成20年度日本生物工学会大会  

    発表年月: 2008年08月

  • Pre-amplified inverse PCRを用いた環境試料からの新規リハ?ーセ?遺伝子の取得

    平成20年度日本生物工学会大会  

    発表年月: 2008年08月

  • Flurorescence Quenching-Based Assay for Monitoring the RNA Helicase Activity of Hepatitis C Virus NS3

    13th Annual Meeting of the RNA Society (RNA 2008)  

    発表年月: 2008年07月

  • Molecular Diversity of Bacterial Chitinases in Arable Soils and Effects of Environmental Factors on Chitinolytic Bacterial Community

    ASM 108th General Meeting  

    発表年月: 2008年06月

  • Phylogenetic Diversity and Abundance of Ammonia-Oxidizing Archaea and Bacteria in Aquarium Biofiltration Systems

    ASM 108th General Meeting  

    発表年月: 2008年06月

  • New Methodologies for Isolation and Cultivation of Unculturable Microorganisms: Hollow Fiber Membrane Chamber and Microbial Cell Chromatography

    ASM 108th General Meeting  

    発表年月: 2008年06月

  • 15N-SIP法による脱窒生態系解析の検討

    環境バイオテクノロジー学会2008年度大会  

    発表年月: 2008年06月

  • 還元を引き金とする蛍光発生分子による遺伝子シグナル増幅システム

    日本ケミカルバイオロジー学会第3回年会  

    発表年月: 2008年05月

  • Real-Time Control Strategy for Simultaneous Nitrogen and Phosphorus Removal Using Aerobic Granular Sludge

    IWA 4th SBR Conference  

    発表年月: 2008年04月

  • Fluorescence Detection of Nucleic Acids Triggered by DNA-Templated Chemical Reaction

    235th ACS National Meeting  

    発表年月: 2008年04月

  • アフィニティーキャピラリー電気泳動法を用いた特定rRNAの連続的定量手法の開発

    日本農芸化学会2008年度大会  

    発表年月: 2008年03月

  • 遺伝子増幅阻害物質の影響を受けにくい新規遺伝子定量手法ABC-LAMP法の開発

    日本農芸化学会2008年度大会  

    発表年月: 2008年03月

  • ABC-PCR法を用いたDehalococcoides属細菌の定量

    日本農芸化学会2008年度大会  

    発表年月: 2008年03月

  • 栄養源に伴う腸内環境変動の微生物群集構造解析法に基づく評価

    日本農芸化学会2008年度大会  

    発表年月: 2008年03月

  • PAI-PCR法による環境試料からの新規遺伝子の取得

    日本農芸化学会2008年度大会  

    発表年月: 2008年03月

  • 遺伝子情報に基づいた新規分子リリースシステムの構築

    日本化学会第88春季年会  

    発表年月: 2008年03月

  • 標的遺伝子上で赤色蛍光を発する新規蛍光プローブの合成

    日本化学会第88春季年会  

    発表年月: 2008年03月

  • 還元反応を引き金とする蛍光発生プローブによる遺伝子シグナルの増幅

    日本化学会第88春季年会  

    発表年月: 2008年03月

  • 化学修飾したダンベル型ナノサークルRNAを用いたRNA干渉法の検討

    日本化学会第88春季年会  

    発表年月: 2008年03月

  • 脱窒性リン蓄積細菌を利用したAOAプロセスにおける炭素源添加濃度の最適化

    第42回日本水環境学会年会  

    発表年月: 2008年03月

  • アナモックス反応に及ぼすメタノールの影響評価

    第42回日本水環境学会年会  

    発表年月: 2008年03月

  • 硝化グラニュールの形成過程における微生物生態構造の変遷

    第42回日本水環境学会年会  

    発表年月: 2008年03月

  • 硝化グラニュールを用いた処理における諸因子の検討

    第42回日本水環境学会年会  

    発表年月: 2008年03月

  • 硝化グラニュールによる窒素含有排水の高速処理

    第42回日本水環境学会年会  

    発表年月: 2008年03月

  • 好気性グラニュールを用いた窒素・リン同時除去手法?リアルタイム制御法の導入による処理の安定化?

    第42回日本水環境学会年会  

    発表年月: 2008年03月

  • 連続式反応槽を用いた好気性グラニュール形成における硝化細菌の重要性

    第42回日本水環境学会年会  

    発表年月: 2008年03月

  • ゼオライト成形体と水生植物を活用した水質浄化技術の窒素除去特性

    第42回日本水環境学会年会  

    発表年月: 2008年03月

  • システム論的アプローチによるバイオフィルム形成の理解

    化学工学会第73年会  

    発表年月: 2008年03月

  • SBMBfR による生物学的窒素・リン除去技術の開発と低C/N比排水への適用

    化学工学会第73年会  

    発表年月: 2008年03月

  • ヒト繊維芽細胞シート皮下移植後の正常ラットと胸腺欠損マウスの急性期生態反応解析

    第7回日本再生医療学会総会  

    発表年月: 2008年03月

  • Tertiary Treatment of Domestic Wastewater Using Zeolite Ceramics and Aquatic Plants

    8th Specialized Conference on Small Water and Wastewater Systems  

    発表年月: 2008年02月

  • Assessment of the Biofilm Model Implementing Kinetic Parameters Estimated by Respirometric Technique through Comparison with Experimental Data

    IWA Biofilm Technologies Conference  

    発表年月: 2008年01月

  • Challenge for Formation of Aerobic Granular Sludge in a Continuous Flow Reactor

    IWA Biofilm Technologies Conference  

    発表年月: 2008年01月

  • ニュートリメタボノミクスにおける安定同位体標識技術の適用

    第30回日本分子生物学会年会・第80回日本生化学会合同大会  

    発表年月: 2007年12月

  • Sequencing Batch Membrane Biofilm Reactor for Simultaneous Nitrogen and Phosphorus Removal: Effect of Membrane Biofilm and Applicability to Low CON/N Wastewater

    BioMicroWorld 2007  

    発表年月: 2007年11月

  • Gene expression profiles of follicle-associated epithelium covering murine intestinal Peyer's patches in response to host-bacterial cross-talk

    第37回日本免疫学会学術集会  

    発表年月: 2007年11月

  • Psg18 is specifically expressed in follicle-associated epithelium

    第37回日本免疫学会学術集会  

    発表年月: 2007年11月

  • 有機性排水流入時におけるanammox反応場の処理性能および細菌群集構造の変化

    日本水処理生物学会第44回大会  

    発表年月: 2007年11月

  • 好気性グラニュールおよびリアルタイム制御法を用いた窒素・リン除去プロセスの開発

    日本水処理生物学会第44回大会  

    発表年月: 2007年11月

  • 河川流入汚濁水路におけるゼオライト成形体と水生植物を活用した水質浄化に関する研究

    日本水処理生物学会第44回大会  

    発表年月: 2007年11月

  • 新規遺伝子定量法ABC-LAMP法の開発

    化学工学会東京大会  

    発表年月: 2007年11月

  • Characterization of the Microbial Community in the Anaerobic/Oxic/Anoxic Process without Excess Sludge Production

    2nd IWA ASPIRE (Asia Pacific Regional Group) Conference  

    発表年月: 2007年10月

  • Nitrogen Removal Performance Using Anaerobic Ammonium Oxidation at Low Temperatures

    2nd IWA ASPIRE (Asia Pacific Regional Group) Conference  

    発表年月: 2007年10月

  • Microbial community of anammox bacteria immobilized in polyethylene glycol gel carrier

    2nd IWA ASPIRE (Asia Pacific Regional Group) Conference  

    発表年月: 2007年10月

  • Systems Microbiological Approach to Understand Biofilms

    13th Symposium of Young Asia Biochemical Engineers Community  

    発表年月: 2007年10月

  • Development of New Methodologies for Cultivating Environmental Microorganisms

    ISME Asia 2007  

    発表年月: 2007年09月

  • Fluorescence Activation System Triggered by Chemical Reaction on Nucleic Acids

    The 2nd International Workshop on Approaches to Single-Cell Analysis  

    発表年月: 2007年09月

  • 中空糸膜隔離分離培養法(HFMC)を用いた環境中の難培養性微生物の分離培養および増殖メカニズムの解析

    平成19年度日本生物工学会大会  

    発表年月: 2007年09月

  • 新規蛍光化合物を用いた遺伝子検出技術の開発

    平成19年度日本生物工学会大会  

    発表年月: 2007年09月

  • 検量線を必要としない簡易な遺伝子定量手法の開発

    平成19年度日本生物工学会大会  

    発表年月: 2007年09月

  • Sequence-based approach による環境試料からの新規遺伝子の探索

    平成19年度日本生物工学会大会  

    発表年月: 2007年09月

  • 新規遺伝子定量手法 Alternately binding quenching probe competitive LAMPにおける阻害物質の影響評価

    日本分析化学会第56年会  

    発表年月: 2007年09月

  • アナモックス菌の外部環境に対する感受性

    第10回日本水環境学会シンポジウム  

    発表年月: 2007年09月

  • System microbiology approach to understand microbial community of biofilm

    第23回日本微生物生態学会  

    発表年月: 2007年09月

  • Characterization of denitrifying bacterial community by using 15N-stable isotope probing

    第23回日本微生物生態学会  

    発表年月: 2007年09月

  • Microbial Cell Chromatography (MCC) as a new concept for concentration of specific microbial cell from environmental communities

    第23回日本微生物生態学会  

    発表年月: 2007年09月

  • 水族館ろ過槽におけるアンモニア酸化能を有する古細菌と真正細菌の多様性解析

    第23回日本微生物生態学会  

    発表年月: 2007年09月

  • リン資源回収型栄養塩除去プロセスにおける微生物叢と処理性能の関係解析

    化学工学会第39回秋季大会  

    発表年月: 2007年09月

  • 電気泳動による微生物固定化空間内の基質輸送の促進と脱窒反応の向上

    化学工学会第39回秋季大会  

    発表年月: 2007年09月

  • 有機化学反応を引き金とする蛍光発生システムの開発と核酸検出への応用

    日本化学会第10回バイオテクノロジー部会シンポジウム  

    発表年月: 2007年09月

  • DNAマイクロアレイを用いた直鎖アルキルベンゼンスルホン酸塩に対するアンモニア酸化細菌Nitrosomonas europaeaの遺伝子発現解析

    環境バイオテクノロジー学会2007年度大会  

    発表年月: 2007年06月

  • Pre-Amplification Technique of Flanking Region for Isolating Entire Gene from Environmental DNA by Inverse PCR

    ASM 107th General Meeting  

    発表年月: 2007年05月

  • New Probes and Autofluorescence Observation that Distinguish aach Subgroup of Defluvicoccus-Relative G-Bacteria in a Wastewater Treatment Process

    ASM 107th General Meeting  

    発表年月: 2007年05月

  • Identification of Bacterial Population Involved in the Methane Oxidation-Coupled Nitrate Depletion under Oxygen-Limited Conditions by Using Stable-Isotope Probing

    ASM 107th General Meeting  

    発表年月: 2007年05月

  • 新規遺伝子定量手法Alternatively Binding Probe Competitive (ABC) PCR法の開発

    第68回分析化学討論会  

    発表年月: 2007年05月

  • Subcutaneous Transplantation of Autologous Oral Muscosal Epithelial Cell Sheets Fabricated on Temperature-Responsive Culture Dishes

    Society of Biomaterials 2007 Annual Meeting  

    発表年月: 2007年04月

  • Community Structure of Nitrifying and Heterotrophic Bacteria in Autotrophic Nitrifying Granules as Characterized by Experimental and Simulation Analysis

    ASM Conferences Biofilms 2007  

    発表年月: 2007年03月

  • ローリングサークル転写反応を用いた蛍光発生RNAアプタマーの増幅による核酸検出

    日本化学会第87春季年会  

    発表年月: 2007年03月

  • 化学反応DNAプローブによる遺伝子検出

    日本化学会第87春季年会  

    発表年月: 2007年03月

  • Catellibacterium nectariphilumの要求する未知生育因子解明の試み

    日本農芸化学会2007年度大会  

    発表年月: 2007年03月

  • システムバイオロジーの方法論を導入した新規微生物生態解析?硝化グラニュール形成メカニズムの解明への適用?

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 連続式反応槽における好気性グラニュールの形成

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 好気性グラニュールの性状に及ぼすポリマー状および粒子状有機物の影響

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 脱窒性リン蓄積細菌を利用したAOAプロセスにおける炭素源添加によるリン取込み阻害モデルの確立

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 有機物が嫌気性アンモニア酸化反応場へ及ぼす影響

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 包括固定化anammox担体内における微生物群集構造の解析

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 多摩川河口干潟における窒素循環に寄与する微生物群の解析

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • メンブレンエアレーション法によって形成されるバイオフィルムの生態構造?実験的解明およびシミュレーション解析?

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 汚泥減容型高度処理プロセスに存在する微生物叢解析

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 高塩濃度条件下で脱窒活性を示す微生物の探索および有用性評価

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • メタン脱窒反応場における炭素循環と細菌群集構造

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 高分子ゲル包括固定化担体を用いた低温硝化プロセスにおける処理特性と硝化菌の挙動

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 連続式および半回分式反応槽における硝化細菌グラニュール形成の比較

    第41回日本水環境学会年会  

    発表年月: 2007年03月

  • 自己口腔粘膜上皮細胞シートの皮下移植

    第8回日本再生医療学会総会  

    発表年月: 2007年03月

  • 高塩濃度条件下における脱窒処理向上のための有用微生物の導入

    第9回化学工学会学生発表会 東京大会  

    発表年月: 2007年03月

  • 硝化・脱窒同時進行型反応場を用いた新規単一槽型N・P同時除去プロセスの開発

    第9回化学工学会学生発表会 東京大会  

    発表年月: 2007年03月

  • 複合微生物系における微生物間コミュニケーションに着目したBiofilm形成制御

    第9回化学工学会学生発表会 東京大会  

    発表年月: 2007年03月

  • 新規分離培養手法を用いたEBPRプロセス内に存在する難培養微生物の獲得および性状評価

    第9回化学工学会学生発表会 東京大会  

    発表年月: 2007年03月

  • 固体表面電位が微生物付着とバイオフィルム形成に及ぼす影響

    第9回化学工学会学生発表会 東京大会  

    発表年月: 2007年03月

  • Quantitative Detection of 16S rRNA in a Microbial Community Using RNA Microarray

    12th Symposium of Young Asia Biochemical Engineers Community  

    発表年月: 2006年11月

  • Stable-Isotope Probing 法によるメタン脱窒反応場の細菌群集構造解析

    日本水処理生物学会第42回大会  

    発表年月: 2006年11月

  • 汚泥減容・リン回収型栄養塩類除去プロセスに生息する微生物叢解析

    日本水処理生物学会第42回大会  

    発表年月: 2006年11月

  • 有機物存在下における嫌気性アンモニア酸化反応の特性解析

    日本水処理生物学会第42回大会  

    発表年月: 2006年11月

  • 低水温条件が及ぼす嫌気性アンモニア酸化活性への影響

    日本水処理生物学会第42回大会  

    発表年月: 2006年11月

  • 高濃度アンモニア含有排水処理プロセスにおける低水温下での処理特性と硝化細菌の挙動

    日本水処理生物学会第42回大会  

    発表年月: 2006年11月

  • Real-time PCR法を用いたanammox細菌の定量と窒素除去特性の関係解析

    日本水処理生物学会第43回大会  

    発表年月: 2006年11月

  • 新規遺伝子定量手法ABC-LAMP法を用いたamoA遺伝子の測定

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • セルソーティングと分子生態学的手法による脱窒性リン蓄積細菌の分取および機能解析

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • 固体表面の物理化学的性状がバイオフィルム形成に及ぼす影響?フローセル試験とシミュレーション解析?

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • 多次元バイオフィルムモデルの微生物生態解析への応用

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • Stable-Isotope Probing法でみるメタン脱窒反応場の細菌群集

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • 水族館濾過槽内のアンモニア酸化能を有する古細菌叢の解析

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • 硝化グラニュールの微生物生態構造解析

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • 新規分離培養手法を用いた環境微生物の増殖特性の評価

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • 新規遺伝子定量手法ABC-PCR法を用いたamoA遺伝子の測定

    第22回日本微生物生態学会  

    発表年月: 2006年10月

  • Redox-Stratification Controlled Biofilm for Completely Autotrophic Nitrogen Removal: Modeling the Effect of Substrate Co- versus Counter-Diffusion on Performance

    IWA Biofilm Systems VI  

    発表年月: 2006年09月

  • Experimental and Simulation Analysis of Community Structure of Nitrifying Bacteria in a Membrane-Aerated Biofilm

    IWA Biofilm Systems VI  

    発表年月: 2006年09月

  • Simultaneous Nitrogen and Phosphorus Removal from High Strength Industrial Wastewater Using Aerobic Granular Sludge

    2nd Workshop on Aerobic Granular Sludge  

    発表年月: 2006年09月

  • Combined Approach for Characterization of Community Structure in Nitrifying Granules as Evaluated by Experimental and 2-Dimensional Biofilm Model Analyses

    2nd Workshop on Aerobic Granular Sludge  

    発表年月: 2006年09月

  • RNA Microarrayを用いた環境微生物の定量技術の開発

    化学工学会第38回秋季大会  

    発表年月: 2006年09月

  • 新規遺伝子定量手法であるABC-LAMP法を用いたアンモニア酸化酵素遺伝子の定量

    化学工学会第38回秋季大会  

    発表年月: 2006年09月

  • 新規分離培養手法を用いた環境微生物の分離培養およびその増殖特性の評価

    平成18年度日本生物工学会大会  

    発表年月: 2006年09月

  • Alternatively binding probe method in competitive PCR(ABC-PCR)法を用いた遺伝子組換えダイズ混入率の測定

    平成18年度日本生物工学会大会  

    発表年月: 2006年09月

  • 環境試料からの未知有用遺伝子の迅速取得手法の開発

    平成18年度日本生物工学会大会  

    発表年月: 2006年09月

  • 新規遺伝子定量手法であるAlternatively binding probe method in competitive LAMP(ABC-LAMP)の開発

    平成18年度日本生物工学会大会  

    発表年月: 2006年09月

  • 新規遺伝子定量手法であるAlternatively binding probe method in competitive PCR(ABC-PCR)法の開発

    平成18年度日本生物工学会大会  

    発表年月: 2006年09月

  • メタン資化細菌を導入した窒素除去の機能強化と高度効率化システム導入方策

    第9回日本水環境学会シンポジウム  

    発表年月: 2006年09月

  • 嫌気性アンモニア酸化法による低水温条件下における窒素の除去特性

    第9回日本水環境学会シンポジウム  

    発表年月: 2006年09月

  • 未知遺伝子の迅速取得手法の開発-メタゲノム解析(Sequence-based approach)への展開-

    第9回日本水環境学会シンポジウム  

    発表年月: 2006年09月

  • A Novel Quantitative Competitive LAMP with an Alternatively Binding Probe for Quantification of the Gene Encoding Ammonia Monooxygenase

    11th International Symposium on Microbial Ecology  

    発表年月: 2006年08月

  • Use of Stable-Isotope Probing Approach to Identify Active Bacteria in Methane-Dependent Denitrifying Consortia

    11th International Symposium on Microbial Ecology  

    発表年月: 2006年08月

  • Optimization of the Cell Wall Permealizing Conditions for Highly Sensitive Fluorescence in situ Hybridization

    11th International Symposium on Microbial Ecology  

    発表年月: 2006年08月

  • Method to Prepare the Template DNA for Inverse PCR, and Its Application in Isolation of Novel Gene from Environmental DNA

    11th International Symposium on Microbial Ecology  

    発表年月: 2006年08月

  • Isolation of Novel Lipase Gene from Environmental DNA Using Pre-amplified Inverse PCR

    11th International Symposium on Microbial Ecology  

    発表年月: 2006年08月

  • DNA Microarray-Transcriptional Profiling of Nitrosomonas europaea in Response to Linear Alkylbenzene Sulfonates

    11th International Symposium on Microbial Ecology  

    発表年月: 2006年08月

  • Hollow Fiber Membrane Chamber System as a High-Performance Method for Isolation and Cultivation of Environmental Microorganisms

    11th International Symposium on Microbial Ecology  

    発表年月: 2006年08月

  • Effects of Composition and Injection Stage of Additional Substances on Nutrient Removal Efficiency of the Anaerobic/Aerobic/Anoxic Process

    International Symposium on Environmental Biotechnology 2006  

    発表年月: 2006年07月

  • Characterization of the High-Density Compounds Containing Organisms in Enhanced Biological Phosphorus Removal Process

    International Symposium on Environmental Biotechnology 2006  

    発表年月: 2006年07月

  • Identification of Denitrifying Polyphosphate-Accumulating Organisms Based on their Functions by Flow Cytometric Sorting

    International Symposium on Environmental Biotechnology 2006  

    発表年月: 2006年07月

  • Microbial Community and Growth Characteristic of Bacteria Exhibiting a High Anaerobic Ammonium Oxidation Activity

    International Symposium on Environmental Biotechnology 2006  

    発表年月: 2006年07月

  • 好気性グラニュールの微生物生態構造解析

    環境バイオテクノロジー学会2006年度大会  

    発表年月: 2006年06月

  • 環境微生物の新規分離培養手法

    環境バイオテクノロジー学会2006年度大会  

    発表年月: 2006年06月

  • メンブレンエアレーション法を導入した半回分式リアクターによる新しい排水処理技術

    環境バイオテクノロジー学会2006年度大会  

    発表年月: 2006年06月

  • Community Analysis of Denitrifying Bacteria Responsible for High-Rate Denitrification in High-Salinity Wastewater System

    ASM 106th General Meeting  

    発表年月: 2006年05月

  • Use of Real-Time PCR to Examine the Relationship between Ammonia Oxidizing Bacterial Populations and Nitrogen Removal Efficiency in a Small Decentralized Treatment System "Johkasou"

    IWA 7th Specialised Conference on Small Water and Wastewater Treatment Systems  

    発表年月: 2006年03月

  • Experimental Support for the Individual-Based Modeling of a Membrane-Aerated Biofilm

    Biofilms II -Attachment and Detachment in Pure and Mixed Cultures-  

    発表年月: 2006年03月

  • Positively Charged Surface is a Determining Factor on Nascent Bacterial Adhesion and Subsequent Biofilm Formation

    Biofilms II -Attachment and Detachment in Pure and Mixed Cultures-  

    発表年月: 2006年03月

  • 高塩濃度条件下において脱窒反応を担っている微生物群の生態解析

    化学工学会第71年会  

    発表年月: 2006年03月

  • 環境中におけるmicrocystin産生藍藻類の定量的解析

    化学工学会第71年会  

    発表年月: 2006年03月

  • バイオフィルムにおける微生物生態構造のシミュレーション解析および実験的解明

    化学工学会第71年会  

    発表年月: 2006年03月

  • 生物学的リン除去プロセスにおける微生物間基質資化競合関係解析

    化学工学会第71年会  

    発表年月: 2006年03月

  • マイクロバブル化オゾン酸化法および吸着脱リン法を組み込んだ新しい資源循環型排水処理プロセス

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 好気性グラニュールを用いた窒素・リン同時除去手法?畜産排水処理への適用?

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 生物学的リン除去リアクター内の環境を模擬可能な環境微生物の新規分離培養法

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 生物学的リン除去プロセスに存在するG-bacteriaの生態解析

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • Microcystin合成遺伝子を指標とした湖沼における藍藻類の毒素産生能の定量評価

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 脱窒性リン蓄積細菌を利用したAOAプロセスにおける添加基質と添加条件変化による挙動解析

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • ゼオライト成形体を活用した生態工学的水質浄化手法の機能強化と浄化メカニズムの解明に関する研究

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 連続培養系に存在する嫌気性アンモニア酸化細菌の群集構造および増殖特性

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 嫌気性アンモニア酸化反応への共存有機物質の影響

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 構造の異なる担体を充填した高度合併処理浄化槽における処理性能と硝化細菌の年間モニタリング

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 各種産業廃水の生物学的窒素除去における硝化細菌グラニュールの有用性

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 単一槽内での独立栄養性窒素除去を志向した新しい生物膜法の性能予測 ?並行拡散方式と対向拡散方式の比較?

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 硝化細菌グラニュールのバイオオーグメンテーションへの応用

    第40回日本水環境学会年会  

    発表年月: 2006年03月

  • 難培養微生物の有用遺伝子取得技術の開発

    文部科学省研究費補助金・特定領域「ゲノム」4領域 第8回ワークショップ「微生物ゲノム研究のフロンティア」  

    発表年月: 2006年03月

  • DNAマイクロアレイを用いたアンモニア酸化細菌への直鎖アルキルベンゼンスルホン酸塩(LAS)の影響評価

    文部科学省研究費補助金・特定領域「ゲノム」4領域 第8回ワークショップ「微生物ゲノム研究のフロンティア」  

    発表年月: 2006年03月

  • QProbe-PCR法による加工食品中の遺伝子組換えダイズ混入率の測定

    第28回日本分子生物学会年会  

    発表年月: 2005年12月

  • 活性汚泥内における高活性な脱窒細菌群集解析のためのStable-isotope probing法の適用

    日本水処理生物学会第42回大会  

    発表年月: 2005年11月

  • 嫌気性アンモニア酸化反応槽内におけるPlanctomycetes に着目した微生物群集構造解析

    日本水処理生物学会第42回大会  

    発表年月: 2005年11月

  • 生物学的リン除去における基質資化競合関係の分子生物学的評価

    日本水処理生物学会第42回大会  

    発表年月: 2005年11月

  • マイクロバブル化オゾン処理および吸着脱リンを組み込んだ新規排水処理プロセスの実用化に向けた検討

    日本水処理生物学会第42回大会  

    発表年月: 2005年11月

  • 水処理プロセスに関与する微生物に高感度FISH を適用するための最適細胞壁消化条件の解析

    日本水処理生物学会第42回大会  

    発表年月: 2005年11月

  • 高度合併処理浄化槽の年間モニタリングにおける処理機能の違いと硝化細菌との関係解析

    日本水処理生物学会第42回大会  

    発表年月: 2005年11月

  • ゼオライト含有セラミックスとヨシ植栽による生態工学手法を活用した水質浄化技術の研究

    日本水処理生物学会第42回大会  

    発表年月: 2005年11月

  • DNA-ナノパーティクル複合体を用いたアフィニティーキャピラリー電気泳動法による特定遺伝子の新規検出手法の開発

    平成17年度日本生物工学会大会  

    発表年月: 2005年11月

  • QProbe-PCR法を用いた食品中の遺伝子組換えダイズ混入率の測定

    平成17年度日本生物工学会大会  

    発表年月: 2005年11月

  • 生物学的リン除去リアクタ内に存在する難培養性微生物の単離及び培養

    平成17年度日本生物工学会大会  

    発表年月: 2005年11月

  • 細菌の細胞壁構造の違いを考慮した高感度FISH操作条件の検討

    平成17年度日本生物工学会大会  

    発表年月: 2005年11月

  • 微生物間相互作用に着目した新規単離培養手法

    平成17年度日本生物工学会大会  

    発表年月: 2005年11月

  • 分子中に多数の水酸基をもつ多糖類のアンチモン吸着能

    第21回日本イオン交換研究発表会  

    発表年月: 2005年11月

  • Anaerobic/Oxic/Anoxic Granular Sludge Process as an Effective Nutrient Removal Process Utilizing Denitrifying Polyphosphate-Accumulating Organisms

    China/USA/Japan Koint Chemical Engineering Conference  

    発表年月: 2005年10月

  • Individual-based Modelによるバイオフィルムの生態構造シミュレーション

    第21回日本微生物生態学会  

    発表年月: 2005年10月

  • 高感度FISHを様々な細菌に適用する際の細胞膜消化条件の検討

    第21回日本微生物生態学会  

    発表年月: 2005年10月

  • 生育環境を模擬することが可能な新規単離培養手法の開発

    第21回日本微生物生態学会  

    発表年月: 2005年10月

  • メンブレンエアレーションバイオフィルムにおける実験的解明およびシミュレーションモデルの構築

    第21回日本微生物生態学会  

    発表年月: 2005年10月

  • 嫌気性アンモニア酸化反応に関わる微生物群の増殖特性

    第21回日本微生物生態学会  

    発表年月: 2005年10月

  • Population Dynamics of Ammonia Oxidizing Bacteria in Full-Scale Advanced Johkasou Using Real-Time PCR Assay

    IWA Specialized Conference on Nutrient Management in Wastewater Treatment Processes and Recycle Streams  

    発表年月: 2005年09月

  • 環境微生物の高感度in situ 検出における問題点

    化学工学会第37回秋季大会  

    発表年月: 2005年09月

  • ジルコニウムフェライト吸着剤によるリン回収工程を組み込んだ新しい排水処理システム

    化学工学会第37回秋季大会  

    発表年月: 2005年09月

  • 多糖分子構造に着目したアンチモン吸着材料の設計

    化学工学会第37回秋季大会  

    発表年月: 2005年09月

  • 水環境再生のためのセラミックス担体導入植栽浄化技術による保全対策の高度化

    第8回日本水環境学会シンポジウム  

    発表年月: 2005年09月

  • Oxidation of Chlorinated Volatile Organic Compounds in a Bubble Column Photochemical Reactor. Determination of the Optical Path Length in Two Reactor Configurations.

    IOA 17th World Ozone Congress  

    発表年月: 2005年08月

  • バイオフィルム内の微生物生態構造の実験的解明およびシミュレーション解析

    化学工学会関東支部50周年記念大会  

    発表年月: 2005年08月

  • 細胞内機能遺伝子のin situ検出手法の体系化

    化学工学会関東支部50周年記念大会  

    発表年月: 2005年08月

  • Characterization of Active Members in EBPR Process by Using MAR-FISH Combined with Buoyant Density Separation

    4th IWA Activated Sludge Population Dynamics Specialist Conference  

    発表年月: 2005年07月

  • Microbial Community Analysis of Anaerobic Ammonium-Oxidizing (Anammox) Bacteria in a Continuous-Feeding Cultivation System

    4th IWA Activated Sludge Population Dynamics Specialist Conference  

    発表年月: 2005年07月

  • Microbial Community of Denitrifying Bacteria for High-Rate Denitrification of Saline Industrial Wastewater

    4th IWA Activated Sludge Population Dynamics Specialist Conference  

    発表年月: 2005年07月

  • Nitrite Reductase (nirS) Genes in an Enhanced Biological Phosphorus Removal Process

    4th IWA Activated Sludge Population Dynamics Specialist Conference  

    発表年月: 2005年07月

  • Real-Time LAMP (Loop-Mediated Isothermal Amplification of DNA) as a Novel and Simple Method for Quantitative Monitoring of Environmental Microorganisms

    4th IWA Activated Sludge Population Dynamics Specialist Conference  

    発表年月: 2005年07月

  • Identification of Polyphosphate-Accumulating Organisms and Glycogen-Accumulating Organisms in Enhanced Biological Phosphorus Removal by Using Density Separation and Molecular Techniques

    1st IWA ASPIRE (Asia Pacific Regional Group) Conference  

    発表年月: 2005年07月

  • Evaluation of Sludge Reduction and Phosphorus Recovery Efficiencies in a New Advanced Wastewater Treatment System Using Denitrifying Polyphosphate Accumulating Organisms

    1st IWA ASPIRE (Asia Pacific Regional Group) Conference  

    発表年月: 2005年07月

  • Development of a New Detection Technique of Specific Gene by Affinity Capillary Electrophoresis

    19th International Symposium on Microscale Bioseparation  

    発表年月: 2005年07月

  • High-Rate Nitrification Using Aerobic Granular Sludge

    3rd IWA Leading-Edge Technology Conference  

    発表年月: 2005年06月

  • Oxidation of Chlorinated Volatile Organic Compounds (CVOCs) in a Bubble Column Photochemical Reactor: Effect of CVOCs on Mass Transfer and Reaction Mechanism

    5th International Symposium on Catalysis in Multiphase Reactors  

    発表年月: 2005年06月

  • Multidimensional Scaling Analysis of the Succession of a Microbial Community Related to Performance of a Wastewater Treatment Process

    The 8th Symposium on Bacterial Genetics and Ecology  

    発表年月: 2005年06月

  • Monitoring the Microbial Population Dynamics at the Start-Up Stage of Wastewater Treatment Reactor Using Terminal Restriction Fragment Length Polymorphism

    The 8th Symposium on Bacterial Genetics and Ecology  

    発表年月: 2005年06月

  • Identification of Denitrifying Population in Activated sludge by Stable-Isotope Probing

    The 8th Symposium on Bacterial Genetics and Ecology  

    発表年月: 2005年06月

  • Q-Probe PCR法を用いた遺伝子組換え大豆の混入率の測定

    環境バイオテクノロジー学会2005年度大会  

    発表年月: 2005年06月

  • DNA-ナノパーティクル複合体を用いたアフィニティーキャピラリー電気泳動法による特定遺伝子の新規な検出手法の開発

    日本農芸化学会2005年度大会  

    発表年月: 2005年03月

  • トップダウンおよびメンブレンエアレーションバイオフィルムにおける硝化細菌群の生態構造の比較

    化学工学会第70年会  

    発表年月: 2005年03月

  • 有機溶媒中で酵素保護機能を有する担体の開発

    化学工学会第70年会  

    発表年月: 2005年03月

  • 材料表面の物理化学的性質が微生物付着およびバイオフィルム形成に及ぼす影響の評価

    化学工学会第70年会  

    発表年月: 2005年03月

  • Rhizopus oligosporusを用いたアンチモンのバイオソープション

    化学工学会第70年会  

    発表年月: 2005年03月

  • アフィニティーキャピラリー電気泳動法による特定遺伝子の新規な検出手法の開発

    化学工学会第70年会  

    発表年月: 2005年03月

  • 回分式反応槽を用いた好気性グラニュールの形成と栄養塩除去への応用

    化学工学会第70年会  

    発表年月: 2005年03月

  • The effect of the gas hold-up structure and the UV radiation absorbing properties of CVOCs on the overall reaction rate during the OH radical induced oxidation treatment in a bubble column photochemical reactor

    化学工学会第70年会  

    発表年月: 2005年03月

  • 原子移動ラジカル重合法を用いて多孔性膜に付与したポリマーブラシのタンパク質吸着による特性評価

    化学工学会第70年会  

    発表年月: 2005年03月

  • メンブレンエアレーション型SBR による窒素・リン同時除去

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 生物学的リン除去プロセスにおいて高活性を示す微生物の特定?密度匂配遠心分離法およびMAR-FISH 法による評価?

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 脱窒性リン蓄積細菌を利用した有機物・窒素・リン同時除去プロセスの開発?添加炭素源濃度と除去率との関係解析?

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 脱窒性リン蓄積細菌の機能を利用したAOA システムにおける余剰汚泥減容化率およびリン回収率の評価・解析

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 高塩濃度条件下で高い脱窒活性を示す微生物群の評価・解析

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 嫌気性アンモニア酸化細菌の増殖に伴う共存微生物群の挙動

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 連続処理系における嫌気性アンモニア酸化細菌の増殖特性

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 嫌気性アンモニア酸化反応系における亜硝酸酸化反応の発見

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 炭素利用特性に着目した活性汚泥の脱窒細菌群集構造?SIP 法による16S rRNA 遺伝子および機能遺伝子解析?

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • Multiwell Filter FISH 法による有用細菌の高感度検出・定量化技術の開発

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 高感度FISH の水処理生態系への適用における課題

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 硝化グラニュールを用いた半導体製造排水処理に関する検討

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 好気性グラニュールを用いた単一槽型新規窒素・リン除去手法の開発

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 高度合併処理浄化槽におけるアンモニア酸化細菌と亜硝酸酸化細菌の年間変動

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • rRNAを標的とした環境微生物DNA マイクロアレイ操作条件の最適化

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 硫酸塩還元細菌を利用したCd除去プロセスにおける生態構造解析

    第39回日本水環境学会年会  

    発表年月: 2005年03月

  • 材料表面の物理化学的性質と微生物の付着性および付着時の活性との関係

    バイオフィルム研究部会2004年度定例講演会  

    発表年月: 2004年11月

  • 生理機能に着目したポリリン酸蓄積細菌およびグリコーゲン蓄積細菌の特定およびin situ活性評価

    第20回日本微生物生態学会  

    発表年月: 2004年11月

  • CARD-FISH法を用いたmRNAと16S rRNA特定配列の in situ同時検出

    第20回日本微生物生態学会  

    発表年月: 2004年11月

  • 生物担体流動式硝化プロセスにおける硝化細菌の経年変化と処理機能解析

    第20回日本微生物生態学会  

    発表年月: 2004年11月

  • 機能遺伝子に基づいた脱窒性リン蓄積細菌のキャラクタリゼーション

    第20回日本微生物生態学会  

    発表年月: 2004年11月

  • Stable-isotope probing 法を用いたアクティブな脱窒細菌の特異的検出?機能遺伝子と16S rRNA遺伝子による評価?

    第20回日本微生物生態学会  

    発表年月: 2004年11月

  • ポリマーブラシを付与した多孔性中空糸膜に固定した酵素によるバイオディーゼル燃料の生産

    化学工学会沖縄大会  

    発表年月: 2004年11月

  • Rhizopus Oligosporusを用いた金属イオンのバイオソープション

    化学工学会沖縄大会  

    発表年月: 2004年11月

  • SBRリアルタイム制御法を用いた生物学的窒素除去

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • 高塩濃度産業廃水の脱窒処理槽内の微生物叢解析

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • 活性汚泥内に存在するメタノール資化性脱窒細菌群のSIP法による特定

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • 包括固定化担体内の硝化細菌群に及ぼす温度条件の影響解析

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • 生物担体流動式硝化プロセス内のアンモニア酸化細菌と亜硝酸酸化細菌の季節変動と処理機能解析

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • T-RFLP法およびクローニング法の併用による排水処理脱窒細菌群の同定

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • 生物的学リン除去に関与する微生物の特定およびin situ活性評価

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • 連続培養系で集積された嫌気性アンモニア酸化細菌およびその共存微生物の解明

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • 硝化細菌グラニュールを用いた各種アンモニア含有排水の高度処理

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • シリコーンチューブ及び繊維状担体を用いた水素供与型脱室リアクターの開発

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • Multiwell Filter Plateを用いた硝化細菌の多検体高速測定技術の開発

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • 脱窒性リン蓄積細菌を利用した新規高度処理における余剰汚泥減容化率およびリン回収率の評価・解析

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • Real-Time PCR法を用いた有毒藍藻類の定量評価手法の開発

    日本水処理生物学会第41回大会  

    発表年月: 2004年11月

  • Antimony Binding to Polyol Brush onto the Porous Membrane

    10th Asian Pacific Confederation of Chemical Engineering (APCChE 2004)  

    発表年月: 2004年10月

  • Enzymatic Reaction in Organic Solvent Using Immobilized Lipase on the Polymer Brush

    10th Asian Pacific Confederation of Chemical Engineering (APCChE 2004)  

    発表年月: 2004年10月

  • Oxidation of Chlorinated Volatile Organic Compounds (CVOCs) in a Bubble Column Photochemical Reactor

    10th Asian Pacific Confederation of Chemical Engineering (APCChE 2004)  

    発表年月: 2004年10月

  • Feasibility study of a membrane-aerated biofilm reactor to achieve controllable nitrification under oxygen depleted conditions

    4th IWA World Water Congress  

    発表年月: 2004年09月

  • QProbe-PCR法による遺伝子組換えダイズの混入率の測定

    第56回日本生物工学会大会  

    発表年月: 2004年09月

  • Real-Time PCR法を用いた有毒藍藻類の迅速モニタリング手法の開発

    第56回日本生物工学会大会  

    発表年月: 2004年09月

  • LAMP法を用いた環境微生物の定量的モニタリング

    第56回日本生物工学会大会  

    発表年月: 2004年09月

  • 生物膜法の機能強化システム構築のための分子生物学導入支援化技術

    第7回日本水環境学会シンポジウム  

    発表年月: 2004年09月

  • 機能遺伝子をターットとしたポピュレーションダイナミクス解析?可能性・限界と工学的応用への展開?

    第7回日本水環境学会シンポジウム  

    発表年月: 2004年09月

  • Oxidation of chlorinated volatile organic compounds (CVOCs) in a bubble column photochemical reactor. In search for a cost-effective reactor design.

    16th International Congress of Chemical and Process Engineering (CHISA 2004)  

    発表年月: 2004年08月

  • Identification of Active Denitrifying Population in Activated Sludge Using Stable-Isotope-Probing (SIP)

    10th International Symposium on Microbial Ecology  

    発表年月: 2004年08月

  • Loop-Mediated Isothermal Amplification (LAMP) of DNA as a New Method for Quantitative Monitoring of Environmental Bacteria and Their Gene Expression

    10th International Symposium on Microbial Ecology  

    発表年月: 2004年08月

  • Monitoring Complex Bacterial Communities using Terminal Restriction Length Polymorphism: Application to Wastewater Treatment Reactor

    10th International Symposium on Microbial Ecology  

    発表年月: 2004年08月

  • Molecular Diversity of Nitrite Reductase Genes (nirK and nirS) in the Denitrification Reactor of Saline Wastewater Treatment

    10th International Symposium on Microbial Ecology  

    発表年月: 2004年08月

  • Effect of Ammonium Concentration and Temperature on Transcriptional Activity of Ammonia Monooxygenase Gene in Ammonia Oxidizer

    10th International Symposium on Microbial Ecology  

    発表年月: 2004年08月

  • 嫌気性アンモニア酸化細菌の集積培養および微生物群の解析

    第41回下水道研究発表会  

    発表年月: 2004年07月

  • 材料表面の物理化学的性質と微生物の付着性との関係解析

    化学工学会秋田大会  

    発表年月: 2004年07月

  • 繊維状担体充填型バイオリアクターによるカドミウム除去およびその数学的解析

    化学工学会秋田大会  

    発表年月: 2004年07月

  • Quantitative monitoring of environmental bacteria and their gene expression by using loop-mediated isothermal amplification (LAMP)

    ASM 104th General Meeting  

    発表年月: 2004年05月

  • 修飾・固定化機能を有する酵素固定化担体による有機溶媒中での酵素活性

    化学工学会第69年会  

    発表年月: 2004年04月

  • T-RFLP 法による排水処理微生物叢の簡易・迅速モニタリング

    化学工学会第69年会  

    発表年月: 2004年04月

  • 固定化微生物層における新規な基質供給方法の開発

    化学工学会第69年会  

    発表年月: 2004年04月

  • 糸状菌による金属イオンのバイオソープションとその吸着機構

    化学工学会第69年会  

    発表年月: 2004年04月

  • ポリオールブラシによるアンチモンの吸着特性

    化学工学会第69年会  

    発表年月: 2004年04月

  • MOTISモデルによる粒状担体膨張層型排水処理装置の数学的解析

    化学工学会第69年会  

    発表年月: 2004年04月

  • 生物膜内の細胞外ポリマーを考慮した拡散-反応モデルの構築

    化学工学会第69年会  

    発表年月: 2004年04月

  • Cellular Automata モデルによる排水処理生物膜内のポピュレーションダイナミクス解析

    化学工学会第69年会  

    発表年月: 2004年04月

  • 硝化・脱窒同時進行型反応場を用いた新規窒素除去プロセスの開発

    化学工学会第69年会  

    発表年月: 2004年04月

  • 高塩濃度産業廃水の生物学的脱窒処理技術の確立

    化学工学会第69年会  

    発表年月: 2004年04月

  • 硫酸還元バイオリアクターによるカドミウム回収および解析

    化学工学会第69年会  

    発表年月: 2004年04月

  • Quenching Probe - PCR(QP-PCR)法を用いた遺伝子組換えダイズの定量分析

    日本農芸化学会2004年度大会  

    発表年月: 2004年03月

  • 脱窒性リン蓄積細菌を利用した単一槽型新規栄養塩除去プロセスの特性評価

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 高分子ゲルに包括固定化された硝化細菌群の低温条件下における挙動

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 生物学的リン除去を担う有用微生物の特定?MAR-FISH法による評価?

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 定量PCR法による高度合併処理浄化槽内の硝化細菌の定量

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 機能遺伝子の空間分布解析による硝化・脱窒同時進行型反応場のキャラクタリゼーション

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 硝化細菌グラニュールの形成機構の解明および粒径別キャラクタリゼーション

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • SBRリアルタイム制御法を用いた亜硝酸型硝化・脱窒プロセスの検討

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 各種アンモニア含有排水の高度処理における硝化細菌グラニュールの有効性

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • SIP法によって明らかになった活性汚泥中のアクティブな脱窒細菌?メタノールと酢酸を添加した場合の違い?

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • amoAmRNAの転写活性に基づくアンモニア酸化細菌の群集構造に及ぼす窒素濃度および温度の影響解析

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 嫌気性アンモニア酸化反応に関わる微生物の生態構造解析

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 有毒藍藻類の迅速モニタリング手法の開発?アオコ発生予測に向けて?

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 繊維担体充填型バイオリアクターのカドミウム除去特性と硫酸塩還元細菌の生態構造との関係

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 嫌気?好気循環型メタン発酵プロセスにおける電気化学処理の効果解析

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 吸着脱リン法による畜産排水からのリン除去・回収スシテムの解析・評価

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • 高度リン回収および余剰汚泥減容化のための排水処理プロセスの開発

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • T-RFLP法による生物学的排水処理反応槽内のバイオコミュニティー変遷モニタリング

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • CARD-FISH法によるmRNAと16SrRNA特定配列のin situ同時検出

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • LAMP法を用いたmRNAの選択的増幅による特定細菌モニタリング手法の開発

    第38回日本水環境学会年会  

    発表年月: 2004年03月

  • Oxidation of CVOCs in a UV-Bubble Column Photochemical Reactor Applying the UV/H2O2 Technique

    Regional Symposium on Chemical Engineering 2003  

    発表年月: 2003年12月

  • Simulation of Competition within AOB in Biofilms Using a Pseudo-3D CA-Hybrid Model

    ASM Conferences Biofilm 2003  

    発表年月: 2003年11月

  • Real Time PCR法による高度合併処理浄化槽の硝化細菌の動態解析

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • ジルコニウムフェライト吸着剤を用いた畜産排水からのリン除去・回収技術の構築

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • アンモニア酸化細菌の基質濃度および温度に対する活性応答

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • 亜硝酸還元酵素遺伝子(nirK, nirS)に基づいた高塩・高硝酸産業廃水処理プロセス内の微生物群集構造解析

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • 基質資化特性をと亜硝酸還元酵素遺伝子に基づいた排水処理微生物の群集構造解析

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • 活性汚泥におけるN2O還元酵素遺伝子に基づく微生物群集構造解析

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • T-RFLP法による排水処理細菌叢の迅速モニタリング

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • ミクロシスチン合成遺伝子に基づく湖沼における有毒藍藻類の評価・解析

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • 嫌気メタン発酵プロセスの高度効率化のための最適条件の探索

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • 生物学的リン除去プロセスにおける有用微生物の基質資化特性に基づいた活性評価

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • 高度リン回収および余剰汚泥減容化のための排水処理プロセスの開発

    日本水処理生物学会第40回大会  

    発表年月: 2003年11月

  • Introducing Radioactive Substrate to the Microcosm Systems to Study Effects of Nitrogenous Compounds Dosage on the Microbial Population and Material Flux in Aquatic Ecosystem

    2nd IWA Asia-Pacific Regional Conference  

    発表年月: 2003年10月

  • Cultivation-Dependent and -Independent Analysis of Bacterial Community in Aquatic Model Ecosystems

    2nd IWA Asia-Pacific Regional Conference  

    発表年月: 2003年10月

  • Microbial Community Analysis of Toxic Cyanobacteria in Water Environment by Molecular Genetic Tools

    2nd IWA Asia-Pacific Regional Conference  

    発表年月: 2003年10月

  • Stable Isotope Probing (SIP) 法を利用した脱窒細菌群集構造解析

    第19回日本微生物生態学会  

    発表年月: 2003年10月

  • 高塩濃度産業廃水の脱窒プロセスにおける微生物群集構造解析 ?亜硝酸還元酵素遺伝子(nirS, nirK)の多様性?

    第19回日本微生物生態学会  

    発表年月: 2003年10月

  • 柔らかい粒子としての細胞表面電気特性解析と細菌付着現象

    第19回日本微生物生態学会  

    発表年月: 2003年10月

  • バイオフィルム内の機能遺伝子に基づいた空間分布解析

    第6回日本水環境学会シンポジウム  

    発表年月: 2003年09月

  • 複合微生物系における脱窒性リン蓄積細菌の亜硝酸還元酵素遺伝子の探索

    第55回日本生物工学会大会  

    発表年月: 2003年09月

  • Novel Method for Monitoring of Environmental Bacteria by Using Loop-Mediated Isothermal Amplification (LAMP) of DNA

    ASM 103rd General Meeting  

    発表年月: 2003年05月

  • In situ Detection of Ammonia Monooxygenase Gene in a Starved Biofilm

    ASM 103rd General Meeting  

    発表年月: 2003年05月

  • Characterization of Denitrifying Bacteria in Saline and Nitrate Containing Industrial Wastewater Treatment System Based on 16S rRNA and Nitrite Reductase Gene

    ASM 103rd General Meeting  

    発表年月: 2003年05月

  • 生物膜を形成する細菌の付着性と表面電気特性に及ぼす細胞外ポリマーの影響

    化学工学会第68年会  

    発表年月: 2003年03月

  • 16S rDNAおよびnirSに基づいた脱窒細菌のポピュレーション解析

    化学工学会第68年会  

    発表年月: 2003年03月

  • 排水処理プロセスにおける核酸の定量的モニタリング

    化学工学会第68年会  

    発表年月: 2003年03月

  • 細胞内遺伝子増幅技術による機能遺伝子の高感度in situ検出

    化学工学会第68年会  

    発表年月: 2003年03月

  • 生物膜内の基質および酸素濃度分布の数学的解析

    化学工学会第68年会  

    発表年月: 2003年03月

  • 酸化剤および阻害因子の制御によるジクロロメタン酸化分解プロセスの最適化

    化学工学会第68年会  

    発表年月: 2003年03月

  • 排水処理に適用可能な生物膜の脱離モデル

    化学工学会第68年会  

    発表年月: 2003年03月

  • 硫酸還元バイオリアクターによる希薄重金属汚染水からの選択的金属除去

    化学工学会第68年会  

    発表年月: 2003年03月

  • 産業廃水の生物学的窒素除去におけるN2O発生量のインベントリー精緻化

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 回分式嫌気・好気活性汚泥法におけるポリリン酸蓄積細菌の活性評価と挙動解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 脱窒性リン蓄積細菌を利用した新規栄養塩除去プロセスの開発

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • RIトレーサー法を用いた水圏生態系マイクロコズムの物質循環に及ぼす窒素濃度の定量的影響解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 混合状態の異なる脱窒リアクターに存在する亜硝酸還元酵素遺伝子群の比較解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • T-RFLP法を用いた機能遺伝子発現プロファイルの解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • T-RFLP法による排水処理微生物叢の簡易・迅速モニタリング技術の開発

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 分子生物学的手法を導入した脱窒細菌の基質資化特性に基づいた群集構造解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 流入負荷変動に対するアンモニア酸化細菌の活性発現のモニタリング解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 窒素濃度および温度がアンモニア酸化酵素遺伝子の発現に及ぼす影響

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • LAMPを用いた特定細菌モニタリング手法の開発

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 硝化細菌と硫黄脱窒細菌を用いた硝化・脱窒同時進行型反応場の開発

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 硫酸還元型バイオリアクターによる希薄廃水からの重金属回収

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • オゾン活用A2O法における汚泥減容化および窒素・リン高度除去システムの開発

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • キレート多孔性中空糸膜を用いたアンチモン高速回収技術の開発

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • MOTISモデルによる粒状担体膨張層型バイオリアクターの数学的解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 超高速硝化を可能にする硝化細菌グラニュールの創製技術

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • メンブレンエアレーション法による低C/N比排水からの有機物・栄養塩同時除去

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 水温変動および硝化液循環の有無の浄化槽プロセスにおけるCH4, N2Oの発生特性解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 高度合併処理浄化槽におけるアンモニア酸化特性と硝化細菌の個体群動態解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • ヒドロキシラジカル濃度制御によるジクロロメタン酸化分解プロセスの最適化

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 亜酸化窒素還元酵素(nosZ)に基づく嫌気好気活性汚泥法における微生物群集構造解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • 分子生物学的手法を用いた湖沼の有毒藍藻類の評価・解析

    第37回日本水環境学会年会  

    発表年月: 2003年03月

  • Development of Membrane-Aerated Biofilm Reactor Applicable to Ammonia Removal from Industrial Wastewater

    2nd Joint China/Japan Chemical Engineering Symposium  

    発表年月: 2002年11月

  • Loop-mediated isothermal amplification of DNA (LAMP) を用いた核酸モニタリング手法の開発

    第18回日本微生物生態学会  

    発表年月: 2002年11月

  • 細菌の付着性と表面電気特性に及ぼす細胞外ポリマーの影響

    第18回日本微生物生態学会  

    発表年月: 2002年11月

  • 核酸の種類に着目したアンモニア酸化細菌の存在および活性の評価

    第18回日本微生物生態学会  

    発表年月: 2002年11月

  • 細胞外ポリマー(EPS)の関与する細菌細胞の界面動電現象・付着現象

    バイオフィルム研究部会2002年度定例会  

    発表年月: 2002年11月

  • 硫酸塩還元細菌を利用したFe-EDTA分解除去プロセスの確立

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 環境中における有毒藍藻類の分子生物学的評価手法による解析

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 水圏モデル生態系マイクロコズムにおける物質循環に及ぼす窒素の影響解析

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 硫酸還元バイオリアクターによる希薄廃水からの重金属回収

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 生活排水対策としての浄化槽への吸着脱リン法導入による高度化・資源循環システムの構築

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 硝化細菌グラニュール形成技術およびその有用性評価

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 硝化細菌および脱窒細菌を組み合わせて固定した硝化・脱窒同時進行型反応場の開発

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 余剰汚泥の発生を制御した新規活性汚泥処理プロセスの開発

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 水圏生態系モデルにおける細菌叢の分子生物学的解析

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • T-RFLP法による排水処理微生物叢の解析評価

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 起源の異なる活性汚泥の馴養過程における微生物群集構造の変遷

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 高塩分含有産業廃水からの脱窒プロセスにおける亜硝酸還元酵素遺伝子の多様性解析

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 機能に基づいた排水処理微生物検出手法の開発

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 循環式硝化脱窒法におけるDO濃度がN2O発生特性および微生物群集構造に及ぼす影響評価

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 生活排水対策システムの硝化液循環の有無におけるCH4,N2Oの発生特性の解析

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 産業廃水の生物学的窒素除去プロセスにおける亜酸化窒素発生特性〜無機塩類の種類の影響〜

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 木屑の形状差が埋立地浸出水の水質に与える影響

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • キノンプロファイル法による脱窒性リン蓄積細菌のバイオマーカーの特定

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • アンモニア酸化細菌の群集構造と活性発現の排水処理プロセスにおけるモニタリング解析

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 分子生物学的手法を用いた生物学的リン除去プロセスにおける有用微生物の評価・解析

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • 分子生物学的手法を用いた排水処理プロセスにおける脱窒細菌の解析

    日本水処理生物学会第39回大会  

    発表年月: 2002年11月

  • A Novel Bioprocess for the Treatment of Heavy Metal Contaminated Water Using Fibrous Solid Wastes as a Bio-carrier

    52nd Canadian Chemical Engineering Conference  

    発表年月: 2002年10月

  • 生物膜様構造体を用いた硝化・脱窒同時進行型反応場の創製

    平成14年度日本生物工学会大会  

    発表年月: 2002年10月

  • Loop-mediated isothermal amplification of DNA (LAMP) を用いた環境微生物モニタリング技術の開発

    平成14年度日本生物工学会大会  

    発表年月: 2002年10月

  • 定量PCRによる水環境プロセス中における核酸のモニタリング

    第5回日本水環境学会シンポジウム  

    発表年月: 2002年09月

  • 微生物固定化の界面化学

    資源・素材2002  

    発表年月: 2002年09月

  • 細菌細胞の界面動電的キャラクタリゼーション2?細胞外ポリマーの影響?

    第55回コロイドおよび界面化学討論会  

    発表年月: 2002年09月

  • 細菌細胞の界面動電的キャラクタリゼーション1?柔らかい粒子の電気泳動?

    第55回コロイドおよび界面化学討論会  

    発表年月: 2002年09月

  • Kinetic Considerations of UV-bubble Column Reactor for Removal of CVOCs from Gas Phase

    15th Int. Congress of Chemcal and Process Engineering (CHISA2002)  

    発表年月: 2002年08月

  • 超高速アンモニア除去を可能にする硝化グラニュール形成技術の開発

    化学工学会新潟大会  

    発表年月: 2002年08月

  • Quantitative Analysis of Microbial Community in the Denitrification Process of Saline Wastewater Treatment System Using New 16S rRNA- Targeted Oligonucleotide Probes

    The 7th Symposium on Bacterial Genetics and Ecology  

    発表年月: 2002年06月

  • Characterization of Nitrite Reductase Activity Based on Nitrite Reductase Genes (nirS) in Saline Watewater Treatment Processes

    The 7th Symposium on Bacterial Genetics and Ecology  

    発表年月: 2002年06月

  • In Situ PCR for Detection of Ammonia Monooxygenase Gene in a Biofilm

    The 7th Symposium on Bacterial Genetics and Ecology  

    発表年月: 2002年06月

  • RT-PCR DGGE for Monitoring Gene Expression of Ammonia Oxidizer in Wastewater Treatment Process

    The 7th Symposium on Bacterial Genetics and Ecology  

    発表年月: 2002年06月

  • Rapid immobilization of bacterial cells to fibrous collector by heterocoagulation phenomenon and its application to the biological wastewater treatment process

    Interfaces Against Pollution (IAP2002)  

    発表年月: 2002年05月

  • Separation of ultrafine CdS particles from low concentrated cadmium wastewater - a novel treatment method of heavy metal contaminated wastewater based on surface characteristics -

    Interfaces Against Pollution (IAP2002)  

    発表年月: 2002年05月

  • In Situ PCR for Visualizing of Distribution of a Functional Gene "amoA" in Biofilm Regardless of its Activity

    Int. Specialized Conference on Biofilm Monitoring  

    発表年月: 2002年03月

  • Monitoring of Dynamic Transition of Bacterial Community Structure in a Nitrifying Biofilm

    Int. Specialized Conference on Biofilm Monitoring  

    発表年月: 2002年03月

  • Comparison of Detection Specificity of Nitrifying Bacteria in Biofilm Using Fish and in Situ Fluorescence Antibody Method

    International Specilaized Conference on Biofilm Monitoring  

    発表年月: 2002年03月

  • 細菌細胞の界面動電現象ー柔らかい粒子の電気泳動解析ー

    平成14年度資源・素材学会  

    発表年月: 2002年03月

  • 界面特性を利用した細菌細胞の付着脱着の制御

    平成14年度資源・素材学会  

    発表年月: 2002年03月

  • スラグ繊維を付着担体とする硫酸還元バイオリアクターによる希薄廃水からの重金属回収

    平成14年度資源・素材学会  

    発表年月: 2002年03月

  • メンブレンエアレーションリアクタの窒素除去特性と生物膜解析

    化学工学会第67年会  

    発表年月: 2002年03月

  • 生物膜を用いた排水処理における過渡応答の速度論的解析

    化学工学会第67年会  

    発表年月: 2002年03月

  • キノンプロファイル法による生物学的脱リンプロセスの微生物生態解析

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 脱窒性リン蓄積細菌の選択的培養技術の開発と優占化の確認

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • UASB法を用いた硫酸塩還元細菌による難生分解性物質の分解

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 分子生物学的手法と培養法による産業廃水脱窒プロセス内微生物群集構造解析の比較

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • in situ PCR法による生物膜内アンモニア酸化細菌の機能遺伝子の検出

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • mRNA発現に基づいたアンモニア酸化細菌の群集構造解析

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 亜硝酸還元酵素NirSに基づいた微生物群集構造解析

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 硝化細菌群の生態構造変動と処理特性との関係の評価・解析

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 機能遺伝子のmRNA発現に基づいた機能及び活性の定量的解析

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 有機性廃棄物の埋立・分解に伴う浸出水の発生とその処理に関する研究

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 独立栄養細菌を用いた硝化・脱窒同時進行型反応場の創製

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 高濃度硝酸含有廃水の窒素除去に有効な脱窒微生物群 〜微生物の多様性は必要か〜

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 高濃度有機物流入時における浄化槽内硝化細菌の分子生物学的評価解析

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 繊維状廃スラグを利用した高速硝化リアクターの設計理論

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 生活排水の循環式硝化脱窒法におけるDO制御とN2O発生特性との関係解析

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 産業廃水の生物学的窒素除去における塩濃度と亜酸化窒素発生量との関係

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 水圏モデル生態系マイクロコズムにおける物質循環に及ぼすリンの影響解析

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 吸着脱リン法による生活排水の高度処理およびリン再生ステーションの構築

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 繊維状スラグを付着担体とした硫酸還元リアクターによる希薄カドミウムの廃水処理

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 生物膜形成に影響を及ぼす微生物の探索とその特性評価

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 数値解析による生物膜内溶存酸素濃度分布の解明

    第36回日本水環境学会年会  

    発表年月: 2002年03月

  • 産業廃水の生物学的窒素除去プロセスにおける亜酸化窒素発生特性〜塩濃度の影響〜

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • 高濃度に硝酸を含む産業廃水の生物学的脱窒処理〜希釈水の検討〜

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • 亜硝酸還元酵素の多様性に基づいた産業排水処理プロセス内汚泥の微生物群集構造解析

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • 分子生物学的手法と培養法を用いた産業廃水処理プロセスにおける微生物群集構造の比較解析

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • 水圏モデル生態系マイクロコズムにおける物質循環に及ぼすリンの影響評価

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • 循環式硝化脱窒法における運転操作条件とN2O発生特性との関係解析

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • 吸着法を用いたリンの除去と回収条件の評価・解析

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • 硝化グラニュール形成微生物の分子生物学的手法による解析

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • メタノール添加による有機物負荷の増大下における浄化槽内硝化細菌の個体群動態の解析

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • アンモニア酸化活性に関わる機能遺伝子とその発現特性に基づいた微生物群集構造の評価・解析

    日本水処理生物学会第38回大会  

    発表年月: 2001年11月

  • バイオフィルム内における機能遺伝子(amoA)のin situ検出

    第17回日本微生物生態学会  

    発表年月: 2001年11月

  • 高塩濃度産業廃水の脱窒プロセスにおける微生物群集構造解析−分子生物学的手法および培養法による検出結果の比較

    第17回日本微生物生態学会  

    発表年月: 2001年11月

  • Recovery of Antimony from Polyester Textile Wastewater Using Chelating Porous Membrane

    51st Canadian Chemical Engineering Conference  

    発表年月: 2001年10月

  • Ecological Structure Analysis of Nitrifying Bacteria in Various Types Wastewater Treatment Process Using Molecular Biological Techniques

    5th International Symposium on Environmental Biotechnology  

    発表年月: 2001年09月

  • Kinetics of Tetrachloroethylene (PCE) Gas Degradation and Byproducts Formation during UV/H2O2 Treatment in UV-buble Column Reactor

    6th World Congress of Chemical Engineering  

    発表年月: 2001年09月

  • 繊維化スラグの微生物付着担体としての利用と新規硝化リアクターの開発

    化学工学会第34回秋季大会  

    発表年月: 2001年09月

  • 微小電極法を用いた生物膜内酸素浸透深さの測定とシミュレーションによる予測

    化学工学会第34回秋季大会  

    発表年月: 2001年09月

  • 硫酸還元細菌を固定化したスラグウール充填リアクターによるカドミウム廃水処理

    化学工学会第34回秋季大会  

    発表年月: 2001年09月

  • 脱窒細菌の高塩濃度環境への馴化

    平成13年度日本生物工学会大会  

    発表年月: 2001年09月

  • 硝化細菌群の生態構造解析および制御

    平成13年度日本生物工学会大会  

    発表年月: 2001年09月

  • コロイド界面科学を応用した新規水処理バイオプロセスの創生

    資源・素材2001  

    発表年月: 2001年09月

  • ビール粕を原料とする成形炭の水質浄化への適用

    資源・素材2001  

    発表年月: 2001年09月

  • 特定機能および活性評価手法としてのmRNA発現解析−アンモニア酸化活性とamoA mRNAの転写活性−

    第4回日本水環境学会シンポジウム  

    発表年月: 2001年09月

  • 窒素除去の生物膜管理技術の高度化のための分子生物学的手法による硝化細菌群の認識技術

    第4回日本水環境学会シンポジウム  

    発表年月: 2001年09月

  • Analysis of mRNA as an Indicator of Ammonia-Oxidizing Activity Responding to the Environmental Condition

    9th International Symposium on Microbial Ecology  

    発表年月: 2001年08月

  • Direct Detection of Ammonia Monooxygenase Gene in a Biofilm by in situ PCR

    9th International Symposium on Microbial Ecology  

    発表年月: 2001年08月

  • Characterization of Microbial Community in Nitrogen Removal Process of Metallurgic Wastewater by Cultivation and Non-Cultivation Methods

    9th International Symposium on Microbial Ecology  

    発表年月: 2001年08月

  • Quantitative Analysis of amoA Expression in Autotrophic Ammonia-Oxidizing Bacteria by Competitive Reverse Transcription-PCR

    9th International Symposium on Microbial Ecology  

    発表年月: 2001年08月

  • 排水処理プロセスにおける窒素除去能の向上に有効なmRNA発現に基づいた微生物群集構造解析

    化学工学会神奈川大会  

    発表年月: 2001年08月

  • Microbial Community Analysis of a Novel Biological Nutrient Removal Process Configured with Anaerobic/Aerobic/Anoxic Conditions

    3rd IWA International Specialised Conference on Microorganisms in Activated Sludge and Biofilm Processes  

    発表年月: 2001年06月

  • Real-Time Monitoring of Ammonia-Oxidizing Activity in a Nitrifying Biofilm by amoA mRNA Analysis

    3rd IWA International Specialised Conference on Microorganisms in Activated Sludge and Biofilm Processes  

    発表年月: 2001年06月

  • PCR-DGGE Analysis of Denitrifying Bacteria in a Metallurgic Wastewater Treatment Process

    3rd IWA International Specialised Conference on Microorganisms in Activated Sludge and Biofilm Processes  

    発表年月: 2001年06月

  • Detection and Quantification of Expression of amoA by Competitive Reverse Transcription PCR

    3rd IWA International Specialised Conference on Microorganisms in Activated Sludge and Biofilm Processes  

    発表年月: 2001年06月

  • 硝化細菌の界面電気特性の評価とこれを利用した水処理プロセスの開発

    20O1年度バイオフィルム研究会ミニシンポジウム  

    発表年月: 2001年06月

  • 生物膜内における基質・酸素浸透深さおよび微生物活性部位の流入負荷変動に対する応答性

    化学工学会第66年会  

    発表年月: 2001年04月

  • 上向流好気性流動床を用いたグラニュール形成技術および高速硝化技術の開発

    化学工学会第66年会  

    発表年月: 2001年04月

  • バイオオーギュメンテーションを志向した硝化生物膜の生態構造制御

    化学工学会第66年会  

    発表年月: 2001年04月

  • mRNAを指標とした廃水処理プロセスにおけるアンモニア酸化活性の追跡

    化学工学会第66年会  

    発表年月: 2001年04月

  • スラグウールを用いたバクテリア分離法におけるイオン強度変化の影響

    資源・素材学会平成13年度春季大会  

    発表年月: 2001年03月

  • 繊維状スラグを付着担体とした硫酸還元細菌固定床リアクターを用いた希薄カドミウムの廃水処理

    資源・素材学会平成13年度春季大会  

    発表年月: 2001年03月

  • 生活排水処理システムとしての膜分離活性汚泥法における硝化細菌の個体群動態と群集構造の解析

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 紫外線−過酸化水素処理におけるヒドロキシラジカル濃度の影響

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 生物学的排水処理プロセスにおけるアンモニア酸化活性のRT-PCR法を用いた定量的な評価・解析

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 無機性アンモニア含有排水処理プロセスにおけるアンモニア酸化細菌群の分子生物学的解析

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 分子生物学的手法を用いた好塩性脱窒細菌群の多様性解析

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • mRNA発現測定による硝化活性のリアルタイムモニタリング手法の開発

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 生物膜形成に関与する微生物細胞外ポリマーの特定と排水処理プロセスへの応用

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 繊維状廃スラグを固定化した高速硝化リアクターの開発

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 栄養塩除去プロセスにおける脱窒性リン蓄積細菌の影響因子と分子生物学的検出

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 難処理性産業廃水の脱窒プロセスに有効な微生物群集構造の追跡

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • 循環式硝化脱窒活性汚泥法における微生物群集構造とN2O発生特性の解析

    第35回日本水環境学会年会  

    発表年月: 2001年03月

  • Simultaneous Nitrification and Denitirification in a Single Reactor Using Membrane Aerated Biofilm Reactor

    Regional Symposium on Chemical Engineering 2000  

    発表年月: 2000年12月

  • Influence of H2O2 Concentration and Gas Flow Rate on the Photodegradation of Tetrachloroethylene in UV-Bubble Column Reactor

    Advanced Study Institute on Remediation of the Aquatic and Atmospheric Environments by Advanced Oxidation  

    発表年月: 2000年11月

  • 高塩分含有排水の生物学的脱窒プロセスにおける微生物群集構造解析

    第16回日本微生物生態学会  

    発表年月: 2000年11月

  • 生物学的窒素除去プロセスの高度化のための硝化細菌の分子生物学的解析

    第16回日本微生物生態学会  

    発表年月: 2000年11月

  • 硝化細菌の界面動電特性と固体表面への付着性の検討

    第16回日本微生物生態学会  

    発表年月: 2000年11月

  • 上向流好気性流動床による高速硝化技術の開発

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • 硫酸塩還元細菌による難生分解性物質の分解

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • アンモニア酸化活性評価のためのRT-PCR法を用いたamoAの定量的解析

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • mRNAを指標としたアンモニア酸化活性のリアルタイムモニタリングとその有効性

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • 高度コンパクト型合併浄化槽における硝化細菌の分子生物学的解析

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • 循環式硝化脱窒法におけるN2O発生特性に及ぼすSRT等の運転操作条件の影響

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • 電子受容体の違いが脱窒性リン蓄積細菌の群集構造に及ぼす影響

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • 高濃度に硝酸を含む産業廃水の生物学的脱窒処理

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • 分子生物学的手法による無機性排水処理プロセスにおけるアンモニア酸化細菌群の評価・解析

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • 高塩製錬廃水処理システムの微生物群集構造に関する分子生態学的評価・解析

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • 好塩性細菌群の脱窒活性に関する分子生物学的評価・解析

    日本水処理生物学会第37回大会  

    発表年月: 2000年11月

  • Oxidation of 1,2-Naphthoquinone-2-Diazido-5-Sulfonic Acid Sodium Salt in Synthetic Wastewater and in Raw Wastewater by UV/H2O2 Process

    IWA Specialist Conference on Pollution Control and Reclamation in Process Industries  

    発表年月: 2000年09月

  • Oxidation of 1,2-Naphthoquinone-2-Diazido-5-Sulfonic Acid Sodium Salt in Aqueous Media by H2O2/UV Process

    1st Joint China/Japan Chemical Engineering Symposium  

    発表年月: 2000年09月

  • Efficient TOC Removal of Wastewater Containing 1,2-Naphthoquinone-2-diazido-5-sulfonic Acid Sodium Salt with H2O2/UV in a Batch Reactor

    第1回日中化学工学シンポジウム  

    発表年月: 2000年09月

  • Enhancement of Nitrifying Biofilm Formation Using Selected EPS Produced by Heterotrophic Bacteria

    IWA Specialist Conference on EPS  

    発表年月: 2000年09月

  • 食品産業におけるゼロエミッション化のための新しい排水処理システム2

    環境科学会2000年会  

    発表年月: 2000年09月

  • 生物膜法を活用した排水処理と有用生物の認識技術

    第3回日本水環境学会シンポジウム  

    発表年月: 2000年09月

  • PCR-DGGE法による高塩濃度産業廃水処理プロセス内の微生物群集構造解析

    化学工学会第33回秋季大会  

    発表年月: 2000年09月

  • 生物膜内基質拡散モデルを用いた排水処理の速度論的解析

    化学工学会第33回秋季大会  

    発表年月: 2000年09月

  • 微小電極法を用いた生物膜内基質濃度分布の測定

    化学工学会第33回秋季大会  

    発表年月: 2000年09月

  • FISH法と活性染色法の併用による硝化生物膜の生態構造解析

    平成12年度日本生物工学会大会  

    発表年月: 2000年08月

  • 高機能硝化生物膜の創製および生態構造解析

    平成12年度日本生物工学会大会  

    発表年月: 2000年08月

  • Characteristics of Denitrifying Phosphate-Accumulating Organisms Cultivated in Anaerobic/Aerobic Sequencing Batch Reactor

    1st World Congress of the International Water Association  

    発表年月: 2000年07月

  • Population Dynamics of Nitrifying Bacteria in Compact Gappei-JOHKASO Investigated by Fluorescent in situ Hybridization

    5th International Symposium on Environmental Biotechnology  

    発表年月: 2000年07月

  • Application of PCR-DGGE Technique to Analysis of Microbial Population in Metallurgic Wastewater Treatment System

    5th International Symposium on Environmental Biotechnology  

    発表年月: 2000年07月

  • Biological Nitrogen Removal from Industrial Wastewater Discharged from Metal Recovery Processes

    1st World Congress of the International Water Association  

    発表年月: 2000年07月

  • 脱窒性リン蓄積細菌のキャラクタリゼーションと微生物群集解析

    化学工学会つくば大会  

    発表年月: 2000年07月

  • 高機能硝化生物膜の新規創製法の開発とその微生物コンソーシアの解明

    化学工学会つくば大会  

    発表年月: 2000年07月

  • 分子生物学的手法による製錬廃水処理装置内の微生物群集構造解析

    化学工学会つくば大会  

    発表年月: 2000年07月

  • 生物膜形成の影響因子としての微生物細胞外代謝物に関する基礎的な研究

    化学工学会第65年会  

    発表年月: 2000年03月

  • 微生物の界面電気的性質と固体表面への付着性に関する検討

    化学工学会第65年会  

    発表年月: 2000年03月

  • 分子生物学的手法を用いた硝化細菌生物膜の生態学的構造解析

    化学工学会第65年会  

    発表年月: 2000年03月

  • 抗原抗体法による排水処理槽内硝化細菌の個体群動態の解析

    化学工学会第65年会  

    発表年月: 2000年03月

  • 硝酸を含む産業廃水の生物学的脱窒処理およびPCR-DGGE法による微生物相の解析

    化学工学会第65年会  

    発表年月: 2000年03月

  • 生物学的排水処理におけるプロセスマトリクスを用いた速度論的解析

    化学工学会第65年会  

    発表年月: 2000年03月

  • 難生分解性化合物の紫外線酸化分解における最適過酸化水素添加法の検討

    化学工学会第65年会  

    発表年月: 2000年03月

  • PCR-DGGE法を用いた生物処理反応槽内における微生物群集構造の評価・解析

    第34回日本水環境学会年会  

    発表年月: 2000年03月

  • 嫌気好気循環生物膜法における生活排水中の環境ホルモン様物質の除去特性の評価

    第34回日本水環境学会年会  

    発表年月: 2000年03月

  • 生活排水処理における硝化細菌のFISH法による挙動解析

    第34回日本水環境学会年会  

    発表年月: 2000年03月

  • 抗原抗体法,FISH法等を用いた生物膜内硝化細菌の分布特性の評価・解析

    第34回日本水環境学会年会  

    発表年月: 2000年03月

  • メンブレンバイオリアクタを用いた単一槽内における窒素除去システム

    第34回日本水環境学会年会  

    発表年月: 2000年03月

  • 電子受容体として硝酸および亜硝酸態結合酸素を用いた生物学的リン除去の基礎的な検討

    第34回日本水環境学会年会  

    発表年月: 2000年03月

  • Enhancement of Nitrifying Biofilm Formation Using Surface Modified Membrane and Evaluation of Its Nitrification Rate for Inorganic Wastewater

    Regional Symposium on Chemical Engineering 1999  

    発表年月: 1999年11月

  • Dynamic Response of the Three-Phase Fluidized Bed Biofilm Reactor for Wastewater Treatment to Step Change in Inlet Concentration

    Regional Symposium on Chemical Engineering 1999  

    発表年月: 1999年11月

  • Fluorescence in situ Hibridization (FISH) Analysis of Nitrifying Bacteria in Wastewater Treatment Process Biofilm

    Asia-Pacific Biochem. Eng. Conf.  

    発表年月: 1999年11月

  • 感光剤製造工程廃液中の難生分解物質の微生物分解

    日本水処理生物学会第36回大会  

    発表年月: 1999年11月

  • 嫌気好気循環生物膜法における生活排水中の外因性内分泌攪乱物質の除去特性の評価

    日本水処理生物学会第36回大会  

    発表年月: 1999年11月

  • モノクローナル抗体法を用いた生物膜内硝化細菌の挙動解析

    日本水処理生物学会第36回大会  

    発表年月: 1999年11月

  • モノクローナル抗体法を用いた硝化細菌の定量特性の評価

    日本水処理生物学会第36回大会  

    発表年月: 1999年11月

  • PCR-DGGE法を用いた排水処理プロセスにおける微生物群集構造の評価・解析

    日本水処理生物学会第36回大会  

    発表年月: 1999年11月

  • FISH法による生物処理反応槽における硝化細菌を中心とした有用細菌の個体群動態の解析

    日本水処理生物学会第36回大会  

    発表年月: 1999年11月

  • 粉砕厨芥排水の流動曝気生物処理における最適粉砕条件の検討および微小後生動物の影響評価

    日本水処理生物学会第36回大会  

    発表年月: 1999年11月

  • 食品産業におけるゼロエミッション化のための新しい排水処理システム

    環境科学会1999年会  

    発表年月: 1999年11月

  • Kinetics Equation for Simultaneous Oxidation of Total Organic Carbon and Ammonium-Nitrogen in Three-Phase Fluidized Bed Biofilm Reactor

    IAWQ Conference on Biofilm Systems  

    発表年月: 1999年10月

  • Tailoring of Highly Efficient Nitrifying Biofilms in Fluidized Bed for Ammonia-Rich Industrial Wastewater Treatment

    7th IAWQ Asia-Pacific Regional Conference  

    発表年月: 1999年10月

  • メンブレンバイオリアクタによる窒素除去システムにおける生物膜内基質・生成物濃度の測定

    化学工学会第32回秋季大会  

    発表年月: 1999年09月

  • 完全混合型三相流動槽を用いた排水処理プロセスに対する過渡応答の解析

    化学工学会第32回秋季大会  

    発表年月: 1999年09月

  • 抗原抗体法を用いた生物処理反応槽における硝化細菌の個体群動態の解析

    第2回日本水環境学会シンポジウム  

    発表年月: 1999年09月

  • FISH法による硝化細菌生物膜の生態学的構造変化の追跡およびマグネティックビーズを利用したPCR法による硝化細菌の定量手法の開発

    第2回日本水環境学会シンポジウム  

    発表年月: 1999年09月

  • Kinetic Study on Organic Carbon and Ammonia Oxidation in the Three-Phase Fluidized Bed Biofilm Reactor

    化学工学会第64年会  

    発表年月: 1999年03月

  • アンモニア酸化細菌および亜硝酸酸化細菌の相互作用のモノクローナル抗体を用いた解析

    第33回日本水環境学会年会  

    発表年月: 1999年03月

  • 2抗体サンドイッチELISA法と各種硝化細菌定量化手法との比較解析

    第33回日本水環境学会年会  

    発表年月: 1999年03月

  • 蛍光抗体法による生物膜内硝化細菌の検出・定量化手法の開発

    第33回日本水環境学会年会  

    発表年月: 1999年03月

  • 紫外線を用いたジクロロメタンの酸化分解処理における分解生成物の影響

    第33回日本水環境学会年会  

    発表年月: 1999年03月

  • 高い硝化能を有する生物膜の創製と高濃度アンモニア含有産業廃水処理プロセスへの適用

    第33回日本水環境学会年会  

    発表年月: 1999年03月

  • 完全混合型三相流動槽を用いた生活系模擬排水におけるBOD除去特性のモデル解析

    第33回日本水環境学会年会  

    発表年月: 1999年03月

  • モノクローナル抗体法を用いた生物学的硝化反応における硝化細菌の相互作用の解析

    日本水処理生物学会第35回大会  

    発表年月: 1998年11月

  • 蛍光顕微鏡画像解析処理装置を用いたモノクローナル抗体法による硝化細菌の定量化手法の開発

    日本水処理生物学会第35回大会  

    発表年月: 1998年11月

  • 2抗体サンドイッチELISA法による硝化細菌の迅速簡易定量化手法の開発

    日本水処理生物学会第35回大会  

    発表年月: 1998年11月

  • 写真廃液中の難生分解有機物の微生物分解

    日本水処理生物学会第35回大会  

    発表年月: 1998年11月

  • 写真廃液の生物処理技術の開発およびゼロエミッション化の検討

    化学工学会沖縄大会  

    発表年月: 1998年11月

  • Reaction Rate Equations and Kinetic Parameters from Batch Experiments on Three-Phase Fluidized Bed Biofilm Reactor for Wastewater Treatment

    Regional Symposium on Chemical Engineering 1998  

    発表年月: 1998年10月

  • Direct Observation of Nitrifying Biofilms on Particles by Electron Microscopy

    IAWQ International Speciality Conference on Microbial Ecology of Biofilms  

    発表年月: 1998年10月

  • Optimum Design of Anaerobic-Aerobic Bioreactor for Nitrogen Removal from Industrial Wastewater

    48th Canadian Chemical Engineering Conference  

    発表年月: 1998年10月

  • 写真関連産業における廃棄物リサイクル手法の評価およびゼロエミッション化の検討 その2

    環境科学会1998年会  

    発表年月: 1998年10月

  • Kinetic Parameters from Batch Experiments on Three-Phase Fluidized Bed Biofilm Reactor for Wastewater Treatment

    化学工学会第31回秋季大会  

    発表年月: 1998年09月

  • Evaluation of Kinetic Parameters from Concentration Step Change Response of Three-Phase Fluidized Bed Biofilm Reactor for Wastewater Treatment

    IAWQ 19th Biennial International Conference  

    発表年月: 1998年06月

  • Kinetics of Biological Treatment of Phenolic Wastewater in Three-Phase Fluidized Bed Containing Biofilm and Suspended Sludge

    IAWQ 19th Biennial International Conference  

    発表年月: 1998年06月

  • 生物膜中の硝化菌のバイオマスと硝化能との相関

    第32回日本水環境学会年会  

    発表年月: 1998年03月

  • 紫外線によるジクロロメタンの無害化処理技術の開発

    第32回日本水環境学会年会  

    発表年月: 1998年03月

  • 生物膜内の硝化菌バイオマスとアンモニア含有廃水処理における硝化能との関係

    日本水処理生物学会第34回大会  

    発表年月: 1997年11月

  • Biological Treatment for Nitrogen Removal from Industrial Wastewater

    Regional Symposium on Chemical Engineering 1997  

    発表年月: 1997年10月

  • Development of High-Performance Biological System with Anaerobic-Aerobic Biofilm for Treatment of Photographic Processing Wastewater

    47th Canadian Chemical Engineering Conference  

    発表年月: 1997年10月

  • 写真関連産業における廃棄物リサイクル手法の評価およびゼロエミッション化の検討 その1

    環境科学会1997年会  

    発表年月: 1997年10月

  • 紫外線によるジクロロメタン水溶液の分解処理の効率化

    化学工学会第30回秋季大会  

    発表年月: 1997年09月

  • 固体廃棄物よりの貴金属回収工程実廃液の生物学的窒素除去

    化学工学会第30回秋季大会  

    発表年月: 1997年09月

  • 完全混合流型三相流動槽における生物処理に及ぼす流入濃度変動の影響

    化学工学会第62年会  

    発表年月: 1997年03月

  • 高度脱窒生物膜三相流動床循環法による難分解性物質含有写真現像・定着廃液の処理

    第31回日本水環境学会年会  

    発表年月: 1997年03月

  • 活性炭顆粒PVA担体流動化三相流動床を組み込んだ高硝酸・塩濃度廃液の高度脱窒処理

    第31回日本水環境学会年会  

    発表年月: 1997年03月

  • 生物膜法による写真廃液の分解処理に関する基礎的検討

    日本水処理生物学会第33回大会  

    発表年月: 1996年11月

  • 微生物膜法による製錬廃水の窒素除去

    日本水処理生物学会第33回大会  

    発表年月: 1996年11月

▼全件表示

特定課題研究

  • 外来性RNA分解酵素導入による病原細菌の不活化

    2021年   一色 理乃

     概要を見る

    近年,薬剤耐性菌の存在が医療現場における大きな問題となっている。我々は,細菌の自死機構であるトキシン/アンチトキシン機構に着目した。本機構では細菌がストレス因子に暴露された際,RNA分解酵素であるトキシン分子が細胞内に遊離し,そのRNA切断活性を暴走させることで細胞死を誘導する。本研究では,外来のトキシンタンパク質を発現可能なファージを標的細菌に感染させ,細菌の必須遺伝子や薬剤耐性遺伝子の翻訳阻害を起こすことによる感染症治療技術を検討した。その結果,ファージをベクターとした場合のトキシンの増殖抑制効果は一定時間見られるものの,プラスミド保有株と比較して再増殖までの時間が短いことがわかった。

  • 細菌のPersister誘導によるバクテリアルトランスロケーションの予防

    2020年   北岡一樹

     概要を見る

    細菌感染症の治療に関する研究としては,新規抗菌薬を探索する研究が数多く行われているが,困難を極めている。我々は従来の抗菌薬のような殺菌や静菌効果に頼らない新たなアプローチが必要であると考え,細菌をPersisterと呼ばれる休眠状態にすることで増殖を抑制し,感染症治療へ利用することを着想した。本年度は,マウスを用いたバクテリアルトランスロケーション(BT)惹起モデルの作製とインドールによるPersister誘導による予防効果の検証を行った。抗がん剤/ステロイド剤を用いることでBT惹起モデルの作製に成功したが,インドールによる予防効果は確認できなかった。

  • クローナルな微生物集団に見られる表現型の不均一性から探る難培養性解除の糸口

    2020年   一色理乃

     概要を見る

    本研究では,アンモニア酸化細菌Nitrosomonas mobilisおよびNitrosomonas europaeaを用い,集団レベルおよびシングルセルレベルでの増殖速度のばらつきを定量的に評価することを目的とした。集団レベルでの検討の結果,初期細胞密度が低くなるにつれて,増殖速度のばらつきは大きくなり,継代効率は低くなった。また,N. europaeaよりもN. mobilisでばらつきは大きく,継代効率は低くなった。マイクロ流体デバイスを用いたシングルセルレベルでのタイムラプス観察の結果,N. mobilisやN. europaeaは増殖細胞と非増殖細胞が約半数ずつ存在することがわかった。

  • 完全アンモニア酸化能を保持するComammox細菌の分離培養と生理生態特性の解明

    2019年  

     概要を見る

    近年,亜硝酸酸化細菌として知られていたNitrospiraの一部がアンモニア酸化能を持つ完全アンモニア酸化(Comammox)細菌であることが明らかとなった。本研究では,多量のアンモニア態窒素が施肥された茶園の酸性土壌に着目し,Comammox細菌の集積を試みた。50 mMの過剰量の塩化アンモニウムを含む培地をリアクターに供給した際に,pH 6.0の酸性条件下で硝化活性の上昇がみられた。その後pH 5.5に低下させると発生する硝酸濃度は低下したものの,硝化活性は維持された。アンモニア酸化酵素遺伝子amoAに基づき,Comammox細菌の構成を解析した結果, clade Aに属する2つのグループが集積されていることがわかった。これらは,遺伝情報的にも生理学的にも新規性を持ったグループに属すると考えられる。<!-- /* Font Definitions */ @font-face {font-family:"MS 明朝"; panose-1:2 2 6 9 4 2 5 8 3 4; mso-font-alt:"MS Mincho"; mso-font-charset:128; mso-generic-font-family:modern; mso-font-pitch:fixed; mso-font-signature:-536870145 1791491579 134217746 0 131231 0;}@font-face {font-family:Century; panose-1:2 4 6 4 5 5 5 2 3 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:647 0 0 0 159 0;}@font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face {font-family:"\@MS 明朝"; panose-1:2 2 6 9 4 2 5 8 3 4; mso-font-charset:128; mso-generic-font-family:modern; mso-font-pitch:fixed; mso-font-signature:-536870145 1791491579 134217746 0 131231 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0mm; margin-bottom:.0001pt; text-align:justify; text-justify:inter-ideograph; mso-pagination:none; font-size:10.5pt; mso-bidi-font-size:11.0pt; font-family:"Century",serif; mso-fareast-font-family:"MS 明朝"; mso-bidi-font-family:"Times New Roman"; mso-font-kerning:1.0pt;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-family:"游明朝",serif; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}size:612.0pt 792.0pt; margin:99.25pt 30.0mm 30.0mm 30.0mm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;}div.WordSection1 {page:WordSection1;}

  • 環境ストレスによるPersister形成の分子機構解明

    2018年   河合 祐人

     概要を見る

     Persisterとはクローナルな細菌集団の一部で形成され、増殖をほとんど行わないことによって、増殖を標的とする多様な抗菌薬から生き残ることが知られている。また、Persisterは抗菌薬の投与を中止すると再増殖することが知られており、感染症の慢性化に関与することが問題となっている。これまで、当研究室では乳酸発酵遺伝子ldhAが大腸菌Persister形成を誘導することを初めて明らかにした。本研究ではldhA発現によるPersister形成メカニズムの解明を目的とした。コントロールおよびldhA過剰発現株におけるプロトン駆動力およびATP産生量を測定した結果、ldhA発現によってエネルギー代謝は減少せず、むしろ増加することが明らかとなった。以上の結果から、ldhA発現によるPersister形成は既往の経路とは異なり、エネルギーを蓄積することで抗菌薬ストレスから逃れる新たな生存戦略を持つと考えられる。

  • 亜硝酸酸化細菌 Nitrospiraのクオラムセンシング機構の解明

    2017年   藤谷 拓嗣

     概要を見る

    クオラムセンシング(QS)機構は、微生物の細菌密度に依存した活性制御機構である。本研究では、活性汚泥から分離した亜硝酸酸化細菌Nitrospira japonica(NJ1株)のQS機構の特性および活性制御メカニズムを調べた。アシル化ホモセリンラクトン(AHL)合成遺伝子を大腸菌に組み込んで代理発現させた結果、4種類のAHLが検出され、これらのAHLが同株の亜硝酸酸化還元酵素をコードする遺伝子を制御していることが明らかになった。

  • ゲノム解析から探る亜硝酸酸化細菌Nitrospiraの生理生態

    2016年   藤谷拓嗣

     概要を見る

    亜硝酸酸化細菌であるNitrospira sp. ND1株とNitrospira japonicaNJ1株の比較ゲノム解析を行った。ND1株とNJ1株のゲノム配列からコードされている遺伝子を同定した結果、ND1株は4602の候補遺伝子(CDS)を、NJ1株は4151のCDSを保有していることが明らかとなった。各CDSから両株の代謝経路、微生物構造を予測した結果、TCA回路、解糖系、電子伝達系に関して、2系統の分離株で違いは確認されなかった。一方、運動性に関わる鞭毛合成、微生物間コミュニケーション機能に関わるクオラムセンシング機構、および窒素代謝経路の遺伝子に顕著な違いが確認された。

  • 比較解析から迫る亜硝酸酸化細菌Nitrospiraの生態学的ニッチ

    2015年   藤谷拓嗣

     概要を見る

    排水処理場における亜硝酸酸化は,2種類(lineage I,II)のNitrospiraが役割を担っている。本研究では,排水処理場の活性汚泥から獲得したND1株(lineage I)とNJ1株(lineage II)の生理学的性質を比較することで実環境の生態学的ニッチを考察することを目的とした。まず,ND1株は低濃度のアンモニアでも顕著に阻害を受けることがわかった。そこで,両株の競合試験を行ったところ,アンモニアを含まない系ではND1株が,アンモニアを含む系ではNJ1株が優占化した。以上のことから異なるlineage間の生態学的ニッチにおいてアンモニア濃度が重要な因子であることが示唆された。

  • 「ミニ腸管」形成プロセスにみられる生物学的自己組織化現象の数理学的理解

    2014年   加川友己

     概要を見る

    大腸腫瘍の形態が経時的にどのように形成されるのかを観察することは、従来法の技術では困難であったが,腸オルガノイド培養技術の開発により,ヒト検体における腸管上皮の管腔形成異常の動的解析を行うことが可能となった。本研究では,細胞間相互作用の実装が容易なcellular Potts modeling手法を用いて腸オルガノイド形態形成の2次元数理モデルを構築し,腫瘍性上皮細胞由来オルガノイドにみられる異常な形態が,本質的に何によって引き起こされているのかを明らかにすることを目指した。その結果,細胞分裂時の分裂軸や分裂速度の異常が単一管腔・単層構造の崩れをもたらすことが予想された。

  • 環境中のマイクロコロニーを標的とした新規微生物分離培養手法の開発

    2014年  

     概要を見る

    排水処理施設において高度な水処理技術を実現するために,活性汚泥中に生息する微生物の特徴を詳細に把握することは重要である。本研究では,活性汚泥中の微生物の系統と凝集性との関係性を明らかにした。また,セルソーターを利用してsingle cellやmicrocolonyといった単一菌種の形態を選択的に分取し,排水中の栄養塩除去に寄与する特定微生物の単離・濃縮を目指した。

  • 難治性感染症の原因となる休止細菌を標的とする新規薬剤スクリーニング

    2014年  

     概要を見る

    難治感染症の原因として休止細菌の存在が注目されている。抗生物質は細菌の増殖を標的として細胞を死に至らしめるが,休止細菌は細胞増殖を行わないため抗生物質の作用を受けず,複数種の抗生物質に対して寛容性を示し生存し続ける。本研究では,休止細菌を撲滅できる新しい薬剤の開発を目指し,我々が開発した世界初の大腸菌の休止細菌マーカー株を利用して,休止細菌の動態をシングルセルレベルで評価できるマイクロ流路を開発した。

  • 大腸陰窩における細胞アポトーシス動態の数理モデリング

    2013年  

     概要を見る

     生体組織中の恒常性維持の仕組みは、癌と深く関係しており、治療手法を考える上で非常に重要である。その理解のために、存在している多数の細胞及びその動的な振る舞いなど、種々の莫大な要素を含めて考える・計算する必要性がある。そのような作業においては、最適な数理モデルに基づくコンピューターシミュレーションが有効である。この恒常性維持について考える際には、その重要な仕組みである「細胞増殖」と「細胞死」の実装が望ましい。しかし、細胞死の発生確率は健常時では非常に低く、その実装が困難であるためか、既存の数理モデルでは細胞増殖にのみ注目しているものがほとんどであり、細胞死の仕組みについて数理モデルで考察した報告は少ない。そこで本研究では、細胞死の発生が増加する状態、組織中に細胞損傷を引き起こす状態、および誘導刺激が導入された状態に着目した。この数理モデルでは、IBM(Individual-Based Modeling)という、主に生態学で用いられる手法に基づくモデル化が行われており、モデル中の細胞1つ1つに対して設定を行うことで、数多くの細胞から成る組織の振る舞いの模擬を可能にしている。この手法によって、個々の細胞が一律ではなく、それぞれ異なるパラメータに従って動くことが可能になり、各細胞の状態に応じて発生する細胞死を模擬する上で適した手法であると考えられる。また、細胞増殖についてもIBMを用いて模擬することで、おそらく一律ではない各幹細胞の個体差を模擬することができると考えられる。本研究では、恒常性維持に必要な「細胞増殖」と「細胞死」を兼ね備えたモデルを用いて誘導刺激導入時に観測された結果の再現を行った。 本研究では、細胞の入れ替わりが活発に起きている腸上皮組織に着目し、その構造単位である陰窩(いんか)における細胞増殖・分化過程の数理モデル化を試み、組織の恒常性維持機構について定量的な議論を行った。その結果、誘導刺激を受けた際にアポトーシスが誘導される確率やアポトーシスが完了するまでの持続時間が、細胞種ごとに異なるのではないかという予測が立てられた。まず、数理モデルにおいては、陰窩中の細胞種として、自己増殖が可能である幹細胞、幹細胞から分化し一定回数だけ分裂可能であるTA細胞(Transit Amplifying cell、一過性増殖細胞)、TA細胞が一定回数の分裂完了後に分化しそれ以上分裂しない分化細胞の3種類を考えた。なお、TA細胞はその分裂回数ごとに、第1世代から第3世代まで分けて考えた。また、本モデルで仮定した細胞のアポトーシス進行経路では、細胞に誘導刺激(放射線照射を想定)が与えられると、一定確率Pで細胞中に変異が残存し、それを感知して細胞死の誘導が行われる。この数理モデルでシミュレーションを行い、実験から得られたアポトーシス細胞の発生や分布の再現を試みた結果、幹細胞とTA細胞の両方にアポトーシスが起こり、かつPの値がTA細胞の世代ごとに異なることが予測された。具体的には、Pの値はTA細胞第1世代で最も大きく、続いて幹細胞、TA細胞第2世代以降の順に小さくなることが予測された。

  • 難培養性アンモニア酸化細菌・古細菌の革新的分離培養戦略

    2012年   大坂 利文

     概要を見る

     硝化細菌(アンモニア酸化細菌・亜硝酸酸化細菌)は,自然環境における窒素循環,および浄水・排水処理における生物学的窒素除去プロセスを担う重要な細菌である。近年の分子生物学的な手法の発展により,硝化細菌は極限・非極限を問わず環境中に普遍的に生息し,系統学的な多様性も高いことが明らかになっている。しかし,高濃度の基質による阻害・遅い増殖速度・強い凝集性を持つために培養が困難であり,硝化細菌に対する有効な培養手法は未だ確立されていない。本研究では,連続流入式の混合型集積培養槽を用いた高度集積培養,およびセルソーターを用いた選択的分取による一連の新規分離培養手法を考案し,特に培養株の少ない貧栄養の淡水環境由来の硝化細菌の獲得を試みた。 培養開始後350日目に集積培養槽から集積サンプル(硝化細菌占有率70%)を採取し,超音波分散処理およびフィルター濾過を行った。セルソーターのパラメーターを細胞の大きさを示す前方散乱光(Forward scatter; FSC)と細胞の内部構造を示す側方散乱光(Side scatter; SSC)に設定し,96ウェルプレート上で1ウェルにつき1つのマイクロコロニーが入るように分注した。FSCを大きくSSCを小さく設定した結果,硝化細菌の形成するマイクロコロニーを選択的に分取することに成功した。一ヶ月間静置培養を行い,増殖が確