Genomic and Metabolomic Analyses of with Enhanced ε-Poly-l-lysine Production Through Adaptive Laboratory Evolution.

ε-poly-l-lysine (ε-PL), a natural food preservative, has garnered widespread attention. It is mainly produced by , but the production by wild-type strains fails to meet the demands of industrialization. To address this issue, adaptive laboratory evolution (ALE) was successfully employed in this study, subjecting CICC 11022 to environmental stresses such as acidic pH and antibiotics (rifampicin, gentamicin, and streptomycin). As a result of ALE, an evolutionary strain C214 was obtained, exhibiting an increase in ε-PL production and cell growth by 153.23% and 234.51%, respectively, as compared with the original strain. Genomic and metabolic analyses revealed that mutations occurred in genes responsible for transcriptional regulation, transporter, cell envelope, energy metabolism, and secondary metabolite synthesis, as well as the enrichment of metabolites involved in the biosynthesis of ε-PL. These findings hold great significance for elucidating the mechanism underlying ε-PL synthesis.