Unleashing Natural Competence in Lactococcus lactis by Induction of the Competence Regulator ComX

摘要: In biotechnological workhorses like Streptococcus thermophilus and Bacillus subtilis, natural competence can be induced, which facilitates genetic manipulation of these microbes. However, in strains the important dairy starter Lactococcus lactis, has not been established to date. silico analysis complete genome sequences 43 L. lactis revealed late gene sets 2 subsp. cremoris (KW2 KW10) at least 10 strains, including model strain IL1403 plant-derived KF147. The remainder all isolates, displayed genomic decay one or more genes. Nisin-controlled expression regulator comX KF147 resulted induction canonical regulon elicited a state this strain. contrast, NZ9000, was predicted encode an incomplete set, failed induce competence. Moreover, mutagenesis comEA-EC operon abolished comX-driven competence, underlining involvement machinery. Finally, introduction nisin-inducible into nisRK-harboring derivatives KW2 allowed also, expanding phenotype other both subspecies.IMPORTANCE Specific bacterial species are able enter DNA is taken up from environment, allowing novel traits. Strains very cultures for fermentation milk cheese production process, where bacteria contribute flavor texture end product. activation industrially relevant organism accelerate research aiming understand traits facilitate engineering strategies harness biodiversity optimized strains.