Transcriptome profiles of high-lysine adaptation reveal insights into osmotic stress response in Corynebacterium glutamicum

• Published in: Frontiers in bioengineering and biotechnology 2022-08, Vol.10, p.933325-933325
• Main Authors: Wang, Jian, Yang, Jian, Shi, Guoxin, Li, Weidong, Ju, Yun, Wei, Liang, Liu, Jun, Xu, Ning
• Format: Article
• Language: English
• Subjects: Bioengineering and Biotechnology; C. glutamicum; DNA repair; high-lysine stress; molecular chaperon; osmoadaptation; transcriptome profiles
• ISSN: 2296-4185; 2296-4185
• DOI: 10.3389/fbioe.2022.933325

Corynebacterium glutamicum has been widely and effectively used for fermentative production of l -lysine on an industrial scale. However, high-level accumulation of end products inevitably leads to osmotic stress and hinders further increase of l -lysine production. At present, the underlying mechanism by which C. glutamicum cells adapt to high-lysine-induced osmotic stress is still unclear. In this study, we conducted a comparative transcriptomic analysis by RNA-seq to determine gene expression profiles under different high-lysine stress conditions. The results indicated that the increased expression of some metabolic pathways such as sulfur metabolism and specific amino acid biosynthesis might offer favorable benefits for high-lysine adaptation. Functional assays of 18 representative differentially expressed genes showed that the enhanced expression of multiple candidate genes, especially grpE chaperon, conferred high-lysine stress tolerance in C. glutamicum . Moreover, DNA repair component MutT and energy-transducing NADH dehydrogenase Ndh were also found to be important for protecting cells against high-lysine-induced osmotic stress. Taken together, these aforementioned findings provide broader views of transcriptome profiles and promising candidate targets of C. glutamicum for the adaptation of high-lysine stress during fermentation.