Screening of high-yield ε-poly-L-lysine producing strains through ribosome engineering

Abstract:

[Objective] We used ribosme engineering technology, with which antibiotic-resistant strains are resulted from mutations on microbial ribosme, to improve the capacity to produce ε-PL by Streptomyces albulus AS3-14. [Methods] A single drug-resistant mutant was obtained from the original S. albulus AS3-14 with the presence of mutagen of streptomycin. A double drug-resistant mutant S. albulus WG-608 was obtained on the basis of single drug-resistant mutant with the presence of mutagen of rifampicin, of which the ε-PL productivity was improved. [Results] The highest ε-PL-producing strain, named S. albulus WG-608, could produce ε-PL of 3.7 g/L in shake-flask and 53.0 g/L in a 5-L fermentor, 42.3% and 32.5%, respectively higher than that of the parent strain. [Conclusion] Screening of streptomycin and rifampicin resistant strains might be a promising alternative to obtain a high ε-PL-producing S. albulus strain.