Characterization and functional role of Saccharomyces cerevisiae 2,3-butanediol dehydrogenase.
Using a conserved sequence motif, a new gene (YAL060W) of the MDR family has been identified in Saccharomyces cerevisiae. The expressed protein was a stereoespecific (2R,3R)-2,3-butanediol dehydrogenase (BDH). The best substrates were (2R,3R)-2,3-butanediol for the oxidation and (3R/3S)-acetoin and 1-hydroxy-2-propanone for the reduction reactions. The enzyme is extremely specific for NAD(H) as cofactor, probably because the presence of Glu223 in the cofactor binding site, instead of the highly conserved Asp223. BDH is inhibited competitively by 4-methylpyrazole with a K(i) of 34 microM. Yeast could grow on 2,3-butanediol or acetoin as a sole energy and carbon sources, and a 3.6-fold increase in BDH activity was observed when cells were grown in 2,3-butanediol, suggesting a role of the enzyme in 2,3-butanediol metabolism. However, the disruption of the YAL060W gene was not lethal for the yeast under laboratory conditions, and the disrupted strain could also grow in 2,3-butanediol and acetoin. This suggests that other enzymes, in addition to BDH, can also metabolize 2,3-butanediol in yeast.
González
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E
Department of Biochemistry and Molecular Biology, Faculty of Sciences, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona, Spain.
Fernández
M R
MR
Larroy
C
C
Parés
X
X
Biosca
J A
JA
D000093:Acetoin / Q000378:metabolism; D000429:Alcohol Oxidoreductases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D002072:Butylene Glycols / Q000378:metabolism; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004795:Enzyme Stability; D018390:Gene Targeting; D005800:Genes, Fungal; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009243:NAD / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D013379:Substrate Specificity
D002072:Butylene Glycols; D009243:NAD; C026978:2,3-butylene glycol; D000093:Acetoin; D000429:Alcohol Oxidoreductases; C019801:butanediol dehydrogenase