Tohru Kodama

Shinshu University

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Yasuo Igarashi

Southwest University

Yasuji Minoda

Tokyo University of Agriculture

Masaharu Ishii

The University of Tokyo

Takashi Yamakawa

Guidance (United Kingdom)

Toshio Omori

Shibaura Institute of Technology

Nobuhiro Hayashi

Tokyo Institute of Technology

Hirofumi Nishihara

Ibaraki University

Eiji Gotō

Chiba University

Hiroyuki Arai

St. Marianna University School of Medicine

Takaharu Tanaka

Tokyo University of Agriculture and Technology

Cooperative Institutions

The University of Tokyo

100

Tokyo University of Agriculture

Osaka University

Kyoto University

Suntory (Japan)

Shinshu University

Suntory Foundation for Life Sciences

Tohoku University

Tokyo University of Science

Tokyo Institute of Technology

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Glucosylation of quercetin by a cell suspension culture of Vitis sp.

Agricultural and Biological Chemistry (1990)

Tohru Kodama Hidekatsu Ishida Tetsuro Kokubo Takashi Yamakawa Hiroshi Noguchi

A cell suspension culture of a Vitis hybrid converted quercetin to six glucosides. Their structures were identified as quercetin 3-O-β-d-glucopyranoside, quercetin 3,4′-di-O-β-d-glucopyranoside, quercetin 3,7-di-O-β-d-glucopyranoside, isorhamnetin 3-O-β-d-glucopyranoside, isorhamnetin 3,4′-di-O-β-d-glucopyranoside, and isorhamnetin 3,7-di-O-β-d-glucopyranoside by UV, FD-MS, 1H-NMR, 13C-NMR spectroscopy and TLC analysis. The course of conversion was also investigated and it was shown that quercetin 3-O-glucoside reached the maximum yield of 31% in 24 hr and then gradually disappeared accompanied by the production of quercetin 3,4′- and 3,7-di-O-glucosides. Although the same rise and fall relationship was observed between isorhamnetin 3-O-glucoside and isorhamnetin 3,4′- or 3,7-di-O-glucoside, their conversion ratios were much lower than those of quercetin glucosides.

Isorhamnetin

Glucoside

Suspension culture

10.1271/bbb1961.54.3283

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Citations (9)

Computer-aided morphometrical analysis of macroconidia in pathogenic fungi of twig blight on mulberry

Nihon sanshigaku zasshi (1998)

Hirosi Yamaguchi Kentaro Ikeda Hideki Saito Yoichi Matsumoto Masayuki Nozue

10.11416/kontyushigen1930.67.507

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Citations (0)

Expression of the nir and nor genes for denitrification of Pseudomonas aeruginosa requires a novel CRP/FNR‐related transcriptional regulator, DNR, in addition to ANR

FEBS Letters (1995)

Hiroyuki Arai Yasuo Igarashi Tohru Kodama

A gene, designated dnr , was identified in the vicinity of the structural genes for nitrite reductase ( nirS ) and nitric oxide reductase ( norCB ), and the gene for activation of the reductases ( nirQ ) from Pseudomonas aeruginosa . It encodes a protein of 227 amino acids homologous with the CRP/FNR‐family transcriptional regulators. Promoter activities for nirS , nirQ and norCB were considerably reduced in the dnr mutant as well as in the mutant of anr , the other fnr ‐like regulatory gene from P. aeruginosa . This is the first finding that two CRP/FNR‐related regulators are involved in denitrification in one strain.

10.1016/0014-5793(95)00885-d

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Citations (129)

Nitrite activates the transcription of the Pseudomonas aeruginosa nitrite reductase and cytochrome c‐551 operon under anaerobic conditions

FEBS Letters (1991)

Hiroyuki Arai Yasuo Igarashi Tohru Kodama

The transcription of the Pseudomonas aeruginosa denAB operon, which consists of the nitrite reductase and cytochrome c ‐551 genes, is induced under anaerobic conditions. However, under anaerobic non‐denitrifying conditions (anaerobic growth on arginine), the promoter activity of the operon was approximately one‐fifth of that under anaerobic denitrifying conditions (anaerobic growth in the presence of nitrite or nitrate). This result clearly demonstrates that the presence of nitrite or nitrate activates the transcription of P. aeruginosa denAB operon under anaerobic conditions.

10.1016/0014-5793(91)81040-f

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Citations (28)

Methionaquinone is a Direct Natural Electron Acceptor for the Membrane-bound Hydrogenase in Hydrogenobacter thermophilus Strain TK-6.

Agricultural and Biological Chemistry (1991)

Masaharu Ishii Tomokazu Omori Yasuo Igarashi Osao Adachi Minoru Ameyama

The hydrogenase reaction in Hydrogenobacter thermophilus strain TK-6, an obligately autotrophic, thermophilic, aerobic hydrogen-oxidizing bacterium, was studied in the membrane fraction, methionaquinone-depleted membrane, and purified membrane-bound hydrogenase. Both b and c type cytochromes were involved in the hydrogen oxidation. Methionaquinone mediated an electron transport between membrane-bound hydrogenase and cytochrome b560. Methionaquinone was reduced directly by purified hydrogenase. From these results, we conclude that methionaquinone is a direct natural electron acceptor for the membrane-bound hydrogenase in the strain.

Hydrogenase

Electron acceptor

Strain (injury)

Autotroph

Oxidizing agent

10.1271/bbb1961.55.3011

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Citations (7)

Isolation of strictly thermophilic and obligately autotrophic hydrogen bacteria.

Agricultural and Biological Chemistry (1980)

Toshiyuki Kawasumi Yasuo Igarashi Tohru Kodama Yasuji Minoda

Various kinds of hydrogen bacteria, mainly mesophiles,1) some thermophiles2,3) and a strictly thermophile,4,5) have been isolated and reported on their taxonomy, physiology, and application.However, obligately autotrophic hydrogen bacterium is nowhere to be found up to date.We isolated a new type of hydrogen

Isolation

Autotroph

10.1271/bbb1961.44.1985

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Citations (57)

A Comparison of GUS Activity after Liquid- and Air-Heat Shock Treatments in Transgenic Nicotiana plumbaginifolia Harboring the Arabidopsis HSP18.2 Promoter- GUS Chimeric Gene.

Plant Biotechnology (1999)

Masamitsu Moriwaki Takashi Yamakawa Tutomu Washino Tohru Kodama Yasuo Igarashi

We investigated the differences between liquid- and air-heat shock (HS) treatments performed on transgenic Nicotiana plumbaginifolia leaves harboring Arabidopsis HSP18.2 promoter-GUS chimeric gene. The optimum temperatures for heat-induced GUS activity in leaves were 42°C for 2h in liquid-HS treatments, and 45°C for 2h in air-HS treatments. Thus, we found a great difference between the GUS activity in leaves exposed to HS in air and liquid.

Chimeric gene

10.5511/plantbiotechnology.16.303

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Citations (1)

Methionaquinone is a Direct Natural Electron Acceptor for the Membrane-bound Hydrogenase inHydrogenobacter thermophilusStrain TK-6

Agricultural and Biological Chemistry (1991)

Masaharu Ishii Tomokazu Omori Yasuo Igarashi Osao Adachi Minoru Ameyama

Hydrogenase

Electron acceptor

Strain (injury)

Oxidizing agent

10.1080/00021369.1991.10857919

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Production of Anthocyanins byVitisCells in Suspension Culture

Agricultural and Biological Chemistry (1983)

Takashi Yamakawa Shigeaki Kato Kunio Ishida Tohru Kodama Yasuji Minoda

A large amount of anthocyanin was accumulated in the callus tissues of Vitis hybrids without light irradiation. Culture conditions for the production of anthocyanins by Vitis cells in suspension cultures were investigated. High sucrose and low phosphate concentrations brought about a marked increase of anthocyanin formation, while high concentrations of nitrate, phosphate, and 2, 4-D repressed the pigment formation. The effects of these nutrients depended on the concentrations of coexistent ones. Regulation of the aeration rate was important for anthocyanin formation in submerged aerated cultures and light irradiation enhanced anthocyanin formation in cultured cells.

Callus

Suspension culture

10.1080/00021369.1983.10865938

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Citations (14)

Excretion ofl-Tryptophan by Analogue-resistant Mutants ofPseudomonas hydrogenothermophilaTH-1 in Autotrophic Cultures

Agricultural and Biological Chemistry (1982)

Yasuo Igarashi Tohru Kodama Yasuji Minoda

Cells of a thermophilic hydrogen bacterium, Pseudomonas hydrogenothermophila TH-1 were treated with N-methyl-N′-nitro-N-nitrosoguanidine and resulting mutants resistant to tryptophan analogues were selected under autotrophic culture conditions (energy source, H2; carbon source, CO2). A mutant strain, 7922, which was resistant to 2000 µg/ml of 5-methyltryptophan and 200–500 µg/ml of 5-fluorotryptophan, was obtained by two step mutations. This mutant excreted 38–70 µg/ml of tryptophan into flask culture broth and a maximum of 200 µg/ml into jar fermentor broth.

Autotroph

Carbon source

Strain (injury)

10.1080/00021369.1982.10865293

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Citations (5)