Cloning, Expression and Characterization of a Highly Active Alcohol Dehydrogenase for Production of Ethyl (S)-4-Chloro-3-Hydroxybutyrate.

ABSTRACT: A novel alcohol dehydrogenase from Bartonella apis (BaADH) was heterologous expressed in Escherichia coli. Its biochemical properties were investigated and used to catalyze the synthesis of ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE), which is a chiral intermediate of the cholesterol-lowering drug atorvastatin. The purified recombinant BaADH displayed 182.4 U/mg of the specific activity using ethyl 4-chloroacetoacetate as substrate under the conditions of 50 °C in pH 7.0 Tris-HCl buffer. It was stable in storage buffers of pH 7 to 9 and retains up to 96.7% of the initial activity after 24 h. The K m and V max values of BaADH were 0.11 mM and 190.4 ?mol min-1 mg-1, respectively. Synthesis of (S)-CHBE catalyzed by BaADH was performed with a cofactor regeneration system using a glucose dehydrogenase, and a conversion of 94.9% can be achieved after 1 h reaction. Homology modeling and substrate docking revealed that a typical catalytic triad is in contact with local water molecules to form a catalytic system. The results indicated this ADH could contribute to the further enzymatic synthesis of (S)-CHBE.

SUBMITTER: Zhu YH 

PROVIDER: S-EPMC6458232 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature