| Literature DB >> 19894084 |
Masahiro Yamamoto1, Takeshi Ikeda, Hiroyuki Arai, Masaharu Ishii, Yasuo Igarashi.
Abstract
Hydrogenobacter thermophilus TK-6 is a thermophilic, chemolithoautotrophic, hydrogen-oxidizing bacterium that fixes carbon dioxide via the reductive tricarboxylic acid (rTCA) cycle. 2-Oxoglutarate:ferredoxin oxidoreductase (OGOR) is the key enzyme in this cycle that fixes carbon dioxide. The genome of strain TK-6 encodes at least two distinct OGOR enzymes, termed For and Kor. We report here a method for measuring the carboxylation of succinyl-CoA catalyzed by OGORs. The method involves the in vitro coupling of OGOR with ferredoxin and pyruvate:ferredoxin oxidoreductase from strain TK-6, and glutamate dehydrogenase from Sulfolobus tokodaii. Using this method, we determined both the apparent maximum velocities and the K (m) values of For and Kor for the carboxylation of succinyl-CoA. This is the first reported kinetic analysis of carbon fixation catalyzed by OGOR enzymes from the rTCA cycle.Entities:
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Year: 2009 PMID： 19894084 DOI： 10.1007/s00792-009-0289-4
Source DB: PubMed Journal: Extremophiles ISSN： 1431-0651 Impact factor: 2.395