文献类型：期刊文献

英文题名：Cloning and Characterization of a Novel Esterase from Rhodococcus sp. for Highly Enantioselective Synthesis of a Chiral Cilastatin Precursor

作者：Zhang, Yan[1];Pan, Jiang[1];Luan, Zheng-Jiao[1];Xu, Guo-Chao[1];Park, Sunghoon[2];Xu, Jian-He[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Pusan Natl Univ, Dept Chem & Biomol Engn, Pusan, South Korea

年份：2014

卷号：80

期号：23

起止页码：7348

外文期刊名：APPLIED AND ENVIRONMENTAL MICROBIOLOGY

收录：;EI(收录号：20144700218413);WOS:【SCI-EXPANDED(收录号:WOS:000344163700025)】；

基金：This work was financially supported by the National Natural Science Foundation of China (grant no. 21276082); the Ministry of Science and Technology, People's Republic of China (grant no. 2011CB710800 and 2011AA02A210); and the Shanghai Commission of Science and Technology (grant no. 11431921600).

语种：英文

外文关键词：Enantioselectivity - Enzymes - Escherichia coli - Carboxylation - Hydrolysis

摘要：A novel nonheme chloroperoxidase (RhEst1), with promiscuous esterase activity for enantioselective hydrolysis of ethyl (S)-2,2-dimethylcyclopropanecarboxylate, was identified from a shotgun library of Rhodococcus sp. strain ECU1013. RhEst1 was overexpressed in Escherichia coli BL21(DE3), purified to homogeneity, and functionally characterized. Fingerprinting analysis revealed that RhEst1 prefers para-nitrophenyl (pNP) esters of short-chain acyl groups. pNP esters with a cyclic acyl moiety, especially that with a cyclobutanyl group, were also substrates for RhEst1. The K-m values for methyl 2,2-dimethylcyclopropanecarboxylate (DmCpCm) and ethyl 2,2-dimethylcyclopropane carboxylate (DmCpCe) were 0.25 and 0.43 mM, respectively. RhEst1 could serve as an efficient hydrolase for the bioproduction of optically pure (S)-2,2-dimethyl cyclopropane carboxylic acid (DmCpCa), which is an important chiral building block for cilastatin. As much as 0.5 M DmCpCe was enantioselectively hydrolyzed into (S)-DmCpCa, with a molar yield of 47.8% and an enantiomeric excess (ee) of 97.5%, indicating an extremely high enantioselectivity (E = 240) of this novel and unique biocatalyst for green manufacturing of highly valuable chiral chemicals.