Lei Zhao, Ying Lu, Jun Yang, Yu Fang, Lifei Zhu, Zhixiang Ding, Chenhui Wang, Wenjian Ma, Xiaoqing Hu, Xiaoyuan Wang
BACKGROUND: Escherichia coli is an important strain for L-threonine production. Genetic switch is a ubiquitous regulatory tool for gene expression in prokaryotic cells. To sense and regulate intracellular or extracellular chemicals, bacteria evolve a variety of transcription factors. The key enzymes required for L-threonine biosynthesis in E. coli are encoded by the thr operon. The thr operon could coordinate expression of these genes when L-threonine is in short supply in the cell. RESULTS: The thrL leader regulatory elements were applied to regulate the expression of genes iclR, arcA, cpxR, gadE, fadR and pykF, while the threonine-activating promoters PcysH , PcysJ and PcysD were applied to regulate the expression of gene aspC, resulting in the increase of L-threonine production in an L-threonine producing E...
February 24, 2020: Microbial Cell Factories