Strategy for improving L-isoleucine production efficiency in Corynebacterium glutamicum
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As one of the three branched-chain amino acids essential for human body, L-isoleucine is widely used in food, medicine, and feed industries. At present, L-isoleucine is mainly produced by microbial fermentation, and the main production strain is Corynebacterium glutamicum. The biosynthetic pathway of L-isoleucine in C. glutamicum is complex, and the activity of key enzymes and the transcription of key genes in the pathway are strictly regulated. The intracellularly synthesized L-isoleucine is secreted by transporters, and the activity of the transporters is also regulated. These intricate regulatory mechanisms increase the difficulty to engineer the L-isoleucine-producing C. glutamicum. This article focuses on the mechanism of L-isoleucine biosynthesis, secretion, and regulation in C. glutamicum and reviews the various metabolic engineering strategies for improving L-isoleucine production efficiency in C. glutamicum.
KeywordsCorynebacterium glutamicum L-Isoleucine Metabolic engineering Branched-chain amino acids Microbial fermentation L-Isoleucine biosynthesis Metabolic regulation Strain development
This work was supported by the National First-class Discipline Program of Light Industry Technology and Engineering (LITE2018-10), and the Collaborative Innovation Center of Jiangsu Modern Industrial Fermentation.
Compliance with ethical standards
This article does not contain any studies with human or animal subject.
Conflict of interest
The author declares that he has no conflict of interest.
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