Efficient synthesis of an epsilon-hydroxy ester in a space-time yield of 1580 g L-1 d(-1) by a newly identified reductase RhCR

摘要

A new NADH-dependent carbonyl reductase RhCR capable of efficiently reducing the epsilon-ketoester ethyl 8-chloro-6-oxooctanoate (ECOO) to give ethyl (S)-8-chloro-6-hydroxyoctanoate [(S)-ECHO], an important chiral precursor for the synthesis of (R)-alpha-lipoic acid, was identified from Rhodococcus sp. ECU1014. Using recombinant Escherichia coli cells expressing RhCR and glucose dehydrogenase used for the regeneration of cofactor, 440 g L-1 (2 M) of ECOO were stoichiometrically converted to (S)-ECHO in a space-time yield of 1580 g L-1 d(-1) without the external addition of any expensive cofactor. (C) 2014 Elsevier Ltd. All rights reserved.