文献类型：期刊文献

英文题名：Mutation breeding of high avermectin B1a-producing strain by the combination of high energy carbon heavy ion irradiation and sodium nitrite mutagenesis based on high throughput screening

作者：Song, Xiaoqing[1];Zhang, Yun[1];Zhu, Xudong[1];Wang, Yonghong[1,2];Chu, Ju[1,2];Zhuang, Yingping[1,2]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Shanghai Collaborat Innovat Ctr Biomfg Technol, Shanghai 200237, Peoples R China

年份：2017

卷号：22

期号：5

起止页码：539

外文期刊名：BIOTECHNOLOGY AND BIOPROCESS ENGINEERING

收录：;EI(收录号：20174804474003);WOS:【SCI-EXPANDED(收录号:WOS:000415893100006)】；

基金：This work was financially supported by a grant from National Key Basic Research Program of China (973 Program, 2013CB733600) and National Major Scientific and Technological Special Project (2012YQ15008709). The authors are grateful to Qilu pharmacy (Inner Mongolia) Co. Ltd. for providing the parent strain.

语种：英文

外文关键词：avermectin B-1a; miniaturization culture; evaluation of mutagenesis method; high-throughput screening

摘要：Microbial mutation breeding has been widely used because it is one of the most efficient and practical breeding strategies in the fermentation industry. However, different mutagenesis methods cause various degrees of DNA damage to individual microorganisms, which lead to diverse characteristics of the mutants. In this study, the effects of four different mutagenesis methods on the mutation breeding of Streptomyces avermitilis for improving avermectin B1a production were investigated with an optimized liquid microtiter plate (MTP) culture system. First, an effective and feasible MTP system for mutant strain screening was evaluated through the optimization of the oxygen transfer rate and rapid titer determination. Then, high energy carbon heavy ion irradiation, diethyl sulfate, ultraviolet- (UV) irradiation combined with lithium chloride, and sodium nitrite were used as the mutagens for mutation breeding, respectively. Results showed that carbon heavy ion irradiation had the advantages of possessing the highest positive mutation rate and mean-production of positive mutant strains in the first generation. Sodium nitrite treatment resulted in mutant strains with better inherited stability than the other three methods. Through the combined treatment of carbon heavy ion irradiation and sodium nitrite treatment, an inheritstable mutant S. avermitilis S-233 with high avermectin B-1a production was successfully obtained. The fermentation verification in a 500-liter (L) bioreactor demonstrated that the avermectin B-1a produced by mutant S. avermitilis S-233 reached 6818 mu g/mL, which was 23.8% higher than that of parent strains.