文献类型：期刊文献

英文题名：Coevolution of the Activity and Thermostability of an ε-Keto Ester Reductase for Better Synthesis of an (R)-α-Lipoic Acid Precursor

作者：Xu, Yao[1];Chen, Qi[1];Zhang, Zhi-Jun[1];Xu, Jian-He[1];Zheng, Gao-Wei[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai Collaborat Innovat Ctr Biomfg Technol, Shanghai 200237, Peoples R China

年份：2020

卷号：21

期号：9

起止页码：1341

外文期刊名：CHEMBIOCHEM

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000530364300016)】；

语种：英文

外文关键词：asymmetric synthesis; directed evolution; enzyme catalysis; keto ester reductases; lipoic acid

摘要：In this work, we have identified a significantly improved variant (S131Y/Q252I) of the natural epsilon-keto ester reductase CpAR2 from Candida parapsilosis for efficiently manufacturing (R)-8-chloro-6-hydroxyoctanoic acid [(R)-ECHO] through co-evolution of activity and thermostability. The activity of the variant CpAR2(S131Y/Q252I) towards the epsilon-keto ester ethyl 8-chloro-6-oxooctanoate was improved to 214 U mg(-1)-from 120 U mg(-1) in the case of the wild-type enzyme (CpAR2(WT))-and the half-deactivating temperature (T-50, for 15 min incubation) was simultaneously increased by 2.3 degrees C in relation to that of CpAR2(WT). Consequently, only 2 g L-1 of lyophilized E. coli cells harboring CpAR2(S131Y/Q252I) and a glucose dehydrogenase (GDH) were required in order to achieve productivity similar to that obtained in our previous work, under optimized reaction conditions (530 g L-1 d(-1)). This result demonstrated a more economical and efficient process for the production of the key (R)-alpha-lipoic acid intermediate ethyl 8-chloro-6-oxooctanoate.