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] State Key Laboratory of Bioreactor Engineering, Newworld Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China

年份：2013

卷号：15

期号：1

起止页码：75

外文期刊名：Metabolic Engineering

收录：EI(收录号：20125115812672)

语种：英文

外文关键词：Lipids - Alcohols

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-01MS 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 4.53. g/l androst-4-ene-3,17-dione, respectively. ? 2012.