ABSTRACTLactococcus lactissubsp.cremorisstrains are used globally for the production of fermented dairy products, particularly hard cheeses. Believed to be of plant origin,L. lactisstrains that are used as starter cultures have undergone extensive adaptation to the dairy environment, partially through the acquisition of extrachromosomal DNA in the form of plasmids that specify technologically important phenotypic traits. Here, we present a detailed analysis of the eight plasmids ofL. lactisUC509.9, an Irish dairy starter strain. Key industrial phenotypes were mapped, and genes that are typically associated with lactococcal plasmids were identified. Four distinct, plasmid-borne bacteriophage resistance systems were identified, including two abortive infection systems, AbiB and AbiD1, thereby supporting the observed phage resistance ofL. lactisUC509.9. AbiB escape mutants were generated for phage sk1, which were found to carry mutations inorf6, which encodes the major capsid protein of this phage.
Bacteriophage AB-SA01 Cocktail in Combination with Antibiotics against MRSA-VISA Strain in an In Vitro Pharmacokinetic/Pharmacodynamic Model
