文献类型：期刊文献

英文题名：An efficient bioprocess for enzymatic production of l-menthol with high ratio of substrate to catalyst using whole cells of recombinant E. coli

作者：Zheng, Gao-Wei[1]; Pan, Jiang[1]; Yu, Hui-Lei[1]; Ngo-Thi, Minh-Thu[1]; Li, Chun-Xiu[1]; Xu, Jian-He[1]

机构：[1] Laboratory of Biocatalysis and Bioprocessing, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR, China

年份：2010

卷号：150

期号：1

起止页码：108

外文期刊名：Journal of Biotechnology

收录：EI(收录号：20104013277594)

语种：英文

外文关键词：Bacteriology - Cloning - Escherichia coli - Monoterpenes - Esters - Cytology - Gene encoding - Catalysis - Enzymes - Loading

摘要：A gene encoding an esterase of Bacillus subtilis ECU0554 previously isolated from soil was cloned and overexpressed in Escherichia coli BL21. The recombinant esterase (recBsE) showed the best enantioselectivity (E>100) towards dl-menthyl acetate, in contrast to dl-menthyl esters propionate and butyrate. A high ratio of substrate to catalyst (S/C-ratio, ≥50) was achieved in the kinetic resolution of dl-menthyl acetate by using whole cells of recombinant E. coli BL21. Some key parameters of the biocatalytic process, including amount of cosolvent, catalyst loading and substrate loading, were optimized. Compared with the process catalyzed by wild-type whole cells of B. subtilis ECU0554, the second-generation bioprocess using whole cells of recombinant E. coli BL21 afforded a 40-fold improvement in S/C-ratio and a 75-fold improvement in the volumetric productivity per biocatalyst loading. Moreover, the substrate loading was increased up to 200gL-1 (~1M), the biocatalyst loading was reduced to 2.5gL-1 and the space-time yield was improved from 54gL-1d-1 to 202gL-1d-1. ? 2010 Elsevier B.V.