Metabolic Engineering of Escherichia coli for Efficient l-Isoleucine Production based on the Citramalate Pathway

文献类型： 外文期刊

第一作者： Zhang, Qiquan

作者： Zhang, Qiquan;Wang, Yuheng;Wang, Xiaolu;Bai, Yingguo;Wang, Yaru;Wang, Yuan;Tu, Tao;Qin, Xing;Su, Xiaoyun;Yao, Bin;Luo, Huiying;Liu, Xu;Huang, Huoqing;Zhang, Jie

作者机构：

关键词： Escherichia coli; l-isoleucine; metabolic engineering; citramalate pathway; threonine-independent pathway

期刊名称：JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY （ 影响因子：6.2； 五年影响因子：6.4 ）

ISSN： 0021-8561

年卷期： 2025 年 73 卷 19 期

页码：

收录情况： SCI

摘要： l-isoleucine, a value-added branched-chain amino acid, has been widely used in the food, feed, and pharmaceutical industries. However, the production efficiency of l-isoleucine is relatively low due to the complex and inefficient biosynthetic network of the canonical threonine pathway. Here, we report the exploitation of a concise citramalate pathway for the development of an efficient l-isoleucine producer. First, chassis strain and key genes were screened for establishment of the citramalate pathway. Subsequently, a citramalate importer was identified and applied to enhance citramalate's utilization efficiency. Finally, a plasmid-free high-l-isoleucine producer was developed by enhancement of l-isoleucine efflux, optimization of rate-limiting gene expression, and introduction of a nonoxidative glycolysis pathway. Fed-batch fermentation of the final strain in a 10-L bioreactor produced 56.6 g/L l-isoleucine with a productivity of 1.66 g/L/h, which is the highest l-isoleucine titer and productivity reported. This study paves the way for construction of efficient microbial cell factories for production of l-isoleucine and related derivatives based on the citramalate pathway.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序