著者

Ui Sadaharu Hosaka Takeshi Watanabe Kazuhide MIMURA AKlO

出版者

公益社団法人日本生物工学会

雑誌

Journal of fermentation and bioengineering (ISSN:0922338X)

巻号頁・発行日

vol.85, no.1, pp.79-83, 1998-01-25

被引用文献数

3

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A mechanism of 2, 3-butanediol(BD)stereoisomer formation was examined with respect to the BD cycle. The enzymes acetylacetoin synthase, acetylacetoin reductase(AACR), and acetylbutanediol hydrolse(ABDH), which are part of the BD cycle, were found to be present in the cell-free extract of the bacterial strain Bacillus cereus YUF-4, Two kinds of acetylbutanediol(ABD)stereoisomers were produced ill the reduction oF acetylacetoin(AAC)by AACR, which were identified as having 3R, 4R and 3S, 4R configurations by NMR spectroscopy and an enzymic method. The tyro ADD formations were found to be catalyzed independently by two respective enzymes: the former was catalyzed by a NADPH-dependent AACR(3R, 4R-ABD forming)and the latter by a NADH-dependent AACR(3S, 4R-ABD forming). The 3R, 4R-ABD was converted into R, R-BD and the 3S, 4R-ABD into R, S-BD by intracellular ABDH These findings demonstrated the existence of a new BD isomer formation mechanism derived from the BD cycle.