文献类型：期刊文献

英文题名：Identification and engineering of cholesterol oxidases involved in the initial step of sterols catabolism in Mycobacterium neoaurum

作者：Yao, Kang[1];Wang, Feng-Qing[1];Zhang, Huai-Cheng[1];Wei, Dong-Zhi[1]

机构：[1]E China Univ Sci & Technol, Newworld Inst Biotechnol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2013

卷号：15

起止页码：75

外文期刊名：METABOLIC ENGINEERING

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000313882500008)】；

基金：We sincerely appreciate T. Parish (Department of Infectious 82 Tropical Diseases, United Kingdom) for providing plasmids of p2NIL and pGOAL19, and W. R. Jacobs, Jr. (Howard Hughes Medical Institute), for providing plasmid pMV261. This research was financially supported by the Fundamental Research Funds for the Central Universities of China (No. WF1114017), the Postdoctoral Foundation of China (No. 20100170757), the National Special Fund for State Key Laboratory of Bioreactor Engineering (No. 2060204), and the National Natural Science Foundation of China (No. 21206039).

语种：英文

外文关键词：Cholesterol oxidase; Mycobacteria; Sterols; Androst-4-ene-3,17-dione; Androst-1,4-diene-3,17-dione

摘要：Mycobacteria have been modified to transform sterols to produce valuable steroids. Here, we demonstrated that the oxidation of sterols to sterones is a rate-limiting step in the catabolic pathway of sterols in Mycobacterium neoaurum. Two cholesterol oxidases ChoM1 and ChoM2 involved in the step were identified in M. neoaurum and the ChoM2 shared up to 45% identity with other cholesterol oxidases. We demonstrated that the combination of ChoM1 and ChoM2 plays a significant role in this step. Accordingly, we developed a strategy to overcome this rate-limiting step by augmenting the activity of cholesterol oxidases in M. neoaurum strains to enhance their transformation productivity of sterols to valuable steroids. Our results indicated that the augmentation of ChoM2 achieved 5.57 g/l androst-1,4-diene-3,17-dione in M. neoaurum NwIB-01 MS and 6.85 g/l androst-4-ene-3,17-dione in M. neoaurum NwIB-R10, greatly higher than the original yield, 3.87 g/l androst-1,4-diene-3,17-dione and 453 g/l androst-4-ene-3,17-dione, respectively. (C) 2012 Elsevier Inc. All rights reserved.