文献类型：期刊文献

英文题名：Nitrate Metabolism Decreases the Steroidal Alcohol Byproduct Compared with Ammonium in Biotransformation of Phytosterol to Androstenedione by Mycobacterium neoaurum

作者：Wang, Xuedong[1];Chen, Rui[1];Wu, Yuyang[1];Wang, Da[1];Wei, Dongzhi[1]

机构：[1]East China Univ Sci & Technol, New World Inst Biotechnol, State Key Lab Bioreactor Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China

年份：2020

卷号：190

期号：4

起止页码：1553

外文期刊名：APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY

收录：;EI(收录号：20195007803883);WOS:【SCI-EXPANDED(收录号:WOS:000501375700003)】；

基金：This work was supported by the National Natural Science Foundation of China (31570079, 21276083).

语种：英文

外文关键词：Bioconversion; Metabolic redistribution; Nitrate; Phytosterol; Redox level

摘要：In biotransformation of phytosterol to 4-androstene-3,17-dione (AD) by Mycobacterium, the steroidal alcohol (such as 22-hydroxy-23,24-bisnorchol-4-ene-3-one, HBC) was a main byproduct. To weaken the accumulation of this byproduct in sterol biotransformation, ammonium was substituted by nitrate as nitrogen resource. The nitrate was utilized by Mycobacterium and led to metabolic flux shift towards AD production. The ratio of AD/HBC increased maximally from 2.1 to 5.5 and AD production increased correspondently. In the meanwhile, the nitrate metabolism resulted in the decreased intracellular redox level (NADH/NAD(+)) maximally by 59.5% and a slight descent tendency with the increase of the nitrate concentrations. It indicated that the nitrate utilization effectively decreased the steroidal alcohol production by regulating intracellular redox level in sterol biotransformation. These results gave an insight into the mechanism of the steroidal alcohol formation in sterol biodegradation and provided a simple strategy to regulate the metabolic distribution.