Microbial chassis design and engineering for production of amino acids used in food industry

Rational microbial chassis design and engineering for improving production of amino acids have attracted a considerable attention. l-glutamate, l-lysine, l-threonine and l-tryptophan are the main amino acids demanded in the food industry. Systems metabolic engineering and synthetic biology engineering generally are believed as the comprehensive engineering approaches to obtain rationally designed strains and construct high-performance platforms for amino acids. The strategies focus on microbial chassis characterization optimization, precise metabolic engineering such as promoter engineering, modular pathway engineering, transporter engineering, and dynamic switch systems application, and global genome streamline engineering to reduce cell burden. In this review, we summarized the efficient engineering strategies to optimize Corynebacterium glutamicum and Escherichia coli cell factories for improving the production of l-glutamate, l-lysine, l-threonine, and l-tryptophan.