在Bacillus licheniformis中通过多策略组合优化的高水平基因酶生产
Zhimin Qi1, Bo Lei1, Min Xiong1
1State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuhan, Hubei, 430062, PR China.
World journal of microbiology & biotechnology
|April 26, 2024
概括
研究人员设计了一种高产的Bacillus licheniformis菌株,用于增强基因酶 (ChiA) 生产. 这涉及蛋白质工程,宿主修饰和发酵优化,大大提高了工业应用的酶活性.
科学领域:
- 生物技术和分子生物学
- 酶工程是什么? 酶工程是什么?
- 微生物菌株的发展
背景情况:
- 基因酶 (ChiA) 在农业,环境保护,医学和生物技术方面具有广泛的应用.
- 开发具有增强ChiA活动的高产品种对工业可行性至关重要.
研究的目的:
- 为了异质地表达和增强来自Bacillus thuringiensis的细胞外基因酶 (ChiA) 的活性,使用Bacillus licheniformis作为宿主.
- 设计一个强大的微生物平台,用于高水平的ChiA生产.
主要方法:
- 通过结构分析和分子动力学模拟指导的部位定向突变发生 (D116N/E118N) 来进行ChiA的蛋白质工程.
- 在Bacillus licheniformis中优化ChiA表达元素.
- 通过淘汰蛋白酶基因 (aprE,bprA,epr) 和副产品合成基因集群,对Bacillus licheniformis进行遗传修饰.
- 将ChiA表达盒集成到宿主基因组中.
- 优化发酵条件和介质成分.
主要成果:
- 基因酶突变D116N/E118N显示了48%更高的特异活性,更好的热稳定性和pH稳定性.
- 工程 Bacillus licheniformis 菌株 DW2△abelA 在蛋白质酶和副产品基因淘汰后实现了 145.56 U/mL 的细胞外 ChiA 活性.
- 基因组集成和发酵优化进一步提高了ChiA活性,在规模化发酵中达到338.79 U/mL.
结论:
- 一个产量高的产生ChiA的菌株,DW2△abelA,通过多边方法成功构建.
- 这种工程菌株为有效的细胞外基因酶生产提供了坚实的基础.
- 开发的方法可用于优化其他有价值酶的生产.
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