期刊
METABOLIC ENGINEERING
卷 24, 期 -, 页码 181-191出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.ymben.2014.05.005
关键词
3-Ketosteroid-Delta(1)-dehydrogenase; Mycobacteria; Sterols; 9 alpha-Hydroxy-4-androstene-3,17-dione
资金
- Fundamental Research Funds for the Central Universities of China [WF1114017]
- National Special Fund for State Key Laboratory of Bioreactor Engineering [2060204]
- National Natural Science Foundation of China [21206039]
3-Ketosteroid-Delta(1)-dehydrogenase (KstD) is a key enzyme involved in the microbial catabolism of sterols. Here, three homologues of KstD were characterized from Mycobacterium neoaurum ATCC 25795, showing distinct substrate preferences and transcriptional responses to steroids. Single deletion of any MN-kstD failed to result in a stable and maximum accumulation of 9-OHAD due to residual KstD activities. To develop stable 9-OHAD producers, all of these MN-KstDs were inactivated, which led to about 6.02 g l(-1) of 9-OHAD from 15 g l(-1) of phytosterols. However, the product was mixed with 1.55 g l(-1) of AD as a major by-product. To transform AD, the oxygenase component of 3-ketosteroid-9 alpha-hydroxylase (KSH), encoded by kshA, was overexpressed. As a result, the yield of 9-OHAD increased to 7.33 g l(-1) with less than 0.31 g l(-1) of AD and the selectivity of 9-OHAD production was improved to 95-97% among metabolites. (C) 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据