Efficiently activated ε-poly-L-lysine production by multiple antibiotic-resistance mutations and acidic pH shock optimization in Streptomyces albulus.

ABSTRACT: ε-Poly-L-lysine (ε-PL) is a food additive produced by Streptomyces and is widely used in many countries. Working with Streptomyces albulus FEEL-1, we established a method to activate ε-PL synthesis by successive introduction of multiple antibiotic-resistance mutations. Sextuple mutant R6 was finally developed by screening for resistance to six antibiotics and produced 4.41 g/L of ε-PL in a shake flask, which is 2.75-fold higher than the level produced by the parent strain. In a previous study, we constructed a double-resistance mutant, SG-31, with high ε-PL production of 3.83 g/L and 59.50 g/L in a shake flask and 5-L bioreactor, respectively. However, we found that R6 did not show obvious advantages in fed-batch fermentation when compared with SG-31. For further activation of ε-PL synthes

SUBMITTER: Wang L 

PROVIDER: S-EPMC6528598 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature