Diacetyl reductase ((R)-acetoin forming) explained

Diacetyl reductase, (R)-acetoin forming
Ec Number:	1.1.1.303

Diacetyl reductase ((R)-acetoin forming) ((R)-acetoin dehydrogenase) is an enzyme with systematic name (R)-acetoin:NAD⁺ oxidoreductase.^{[1] [2]} This enzyme catalyses the following chemical reaction

(R)-acetoin + NAD⁺

\rightleftharpoons diacetyl + NADH + H⁺

The reaction is catalysed in the reverse direction. This activity is usually associated with butanediol dehydrogenase activity (EC 1.1.1.4 or EC 1.1.1.76). While the butanediol dehydrogenase activity is reversible, diacetyl reductase activity is irreversible. This enzyme has been reported in the yeast Saccharomyces cerevisiae. This enzyme is different from EC 1.1.1.304, diacetyl reductase ((S)-acetoin forming).

Notes and References

1. Heidlas J, Tressl R . Purification and characterization of a (R)-2,3-butanediol dehydrogenase from Saccharomyces cerevisiae . Archives of Microbiology . 154 . 3 . 267–73 . 1990 . 2222122 . 10.1007/bf00248966 . 21979677 .
2. González E, Fernández MR, Larroy C, Solà L, Pericàs MA, Parés X, Biosca JA . Characterization of a (2R,3R)-2,3-butanediol dehydrogenase as the Saccharomyces cerevisiae YAL060W gene product. Disruption and induction of the gene . The Journal of Biological Chemistry . 275 . 46 . 35876–85 . November 2000 . 10938079 . 10.1074/jbc.M003035200 . free .