Highly stereoselective reduction of prochiral ketones by a bacterial reductase coupled with cofactor regeneration

Org Biomol Chem. 2011 Aug 7;9(15):5463-8. doi: 10.1039/c1ob05285c. Epub 2011 Jun 14.

Abstract

A carbonyl reductase gene (yueD) from Bacillus sp. ECU0013 was heterologously overexpressed in Escherichia coli, and the encoded protein (BYueD) was purified to homogeneity and characterized. The NADPH-dependent reductase showed a broad substrate spectrum towards different aromatic ketones, and α- and β-ketoesters. Although the enantioselectivity was high to moderate for the reduction of α-ketoesters, all the tested β-ketoesters and aromatic ketones were reduced to the corresponding chiral alcohols in enantiomerically pure forms. Furthermore, the practical applicability of this enzyme was evaluated for the reduction of ethyl 4-chloro-3-oxobutanoate (1a). Using Escherichia coli cells coexpressing BYueD and glucose dehydrogenase, 215 g L(-1) (1.3 M) of 1a was stoichiometrically converted to ethyl (R)-4-chloro-3-hydroxybutanoate ((R)-1b) in an aqueous-toluene biphasic system by using a substrate fed-batch strategy, resulting in an overall hydroxyl product yield of 91.7% with enantiomeric purity of 99.6% ee.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohol Oxidoreductases / chemistry
  • Alcohol Oxidoreductases / genetics
  • Alcohol Oxidoreductases / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Glucose Dehydrogenases / metabolism*
  • Glucose Dehydrogenases / pharmacology
  • Hydrogen-Ion Concentration
  • Ketones / chemistry*
  • Oxidation-Reduction
  • Stereoisomerism
  • Substrate Specificity
  • Temperature

Substances

  • Ketones
  • Alcohol Oxidoreductases
  • Glucose Dehydrogenases