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ID 34240
フルテキストURL
著者
Takahata, Muneaki Department of Biofunctional Chemistry, Graduate School of Natural Science and Technology, Okayama University
Tamura, Takashi Department of Biofunctional Chemistry, Graduate School of Natural Science and Technology, Okayama University
Abe, Katsumasa Laboratory of Molecular Microbial Science, Institute for Chemical Research, Kyoto University
Mihara, Hisaaki Laboratory of Molecular Microbial Science, Institute for Chemical Research, Kyoto University
Kurokawa, Suguru Laboratory of Molecular Microbial Science, Institute for Chemical Research, Kyoto University
Yamamoto, Yoshihiro Department of Genetics, Hyogo College of Medicine
Nakano, Ryuhei Department of Biofunctional Chemistry, Graduate School of Natural Science and Technology, Okayama University
Esaki, Nobuyoshi Department of Genetics, Hyogo College of Medicine
Inagaki, Kenji Department of Biofunctional Chemistry, Graduate School of Natural Science and Technology, Okayama University
抄録

Escherichia coli growing under anaerobic conditions produce H-2 and CO2 by the enzymatic cleavage of formate that is produced from pyruvate at the end of glycolysis. Selenium is an integral part of formate dehydrogenase H (FDHH), which catalyses the first step in the formate hydrogen lyase (FHL) system. The genes of FHL system are transcribed only under anaerobic conditions, in the presence of a sigma(54)-dependent transcriptional activator Fh1A that binds formate as an effector molecule. Although the formate addition to the nutrient media has been an established procedure for inducing high FDHH activity, we have identified a low-salt nutrient medium containing <0.1% NaCl enabled constitutive, high expression of FDHH even without formate and D-glucose added to the medium. The novel conditions allowed us to study the effects of disrupting genes like trxB (thioredoxin reductase) or gor (glutathione reductase) on the production of FDHH activity and also reductive assimilation of selenite (SeO32-) into the selenoprotein. Despite the widely accepted hypothesis that selenite is reduced by glutathione reductase-dependent system, it was demonstrated that trxB gene was essential for FDHH production and for labelling the FDHH polypeptide with Se-75-selenite. Our present study reports for the first time the physiological involvement of thioredoxin reductase in the reductive assimilation of selenite in E. coli.

キーワード
formate dehydrogenase H
selenite assimilation
thioredoxin reductase
備考
Published with permission from the copyright holder.
This is a author's copy,as published in Journal of Biochemistry , 2008 Vol.143 Issue.4 pp.467-473
Publisher URL: http://dx.doi.org/10.1093/jb/mvm247
Direct access to Thomson Web of Science record
Copyright © 2008 by The Japanese Biochemical Society
発行日
2008-06-26
出版物タイトル
Journal of Biochemistry
143巻
4号
開始ページ
467
終了ページ
473
資料タイプ
学術雑誌論文
言語
English
OAI-PMH Set
岡山大学
査読
有り
DOI
Web of Sience KeyUT
Submission Path
biochemistry/9