An application in cheddar cheese manufacture for a strain of Lactococcus lactis producing a novel broad-spectrum bacteriocin, lacticin 3147.

摘要: Lactococcus lactis DPC3147, a strain isolated from an Irish kefir grain, produces bacteriocin with broad spectrum of inhibition. The produced is heat stable, particularly at low pH, and inhibits nisin-producing (Nip+) lactococci. On the basis observation that nisin structural gene (nisA) does not hybridize to DPC3147 genomic DNA, was considered novel designated lacticin 3147. genetic determinants which encode 3147 are contained on 63-kb plasmid, conjugally mobilized commercial cheese starter, L. subsp. cremoris DPC4268. resultant transconjugant, DPC4275, both immune ability 3147-producing lactococci perform as cheddar starters subsequently investigated in cheesemaking trials. Bacteriocin-producing (which included transconjugant DPC4275) acid rates similar those strains. level remained constant over 6 months ripening correlated significant reduction levels nonstarter lactic bacteria. Such results suggest these provide means controlling developing microflora ripened fermented products.