The plasmid profiling of different strains of Lactococcus lactis Subsp. Lactis

Abstract

Plasmid biology has become an important area of investigation in dairy starters. Genes located on plasmid DNA code some properties vital for successful milk fermentations. Some of the metabolic properties observed in lactic streptococci have been clearly established as being plasmid mediated, which makes them an unstable character during subsequent subculturing. Strains of L.lactis subsp. Lactis ML3, ML8 and C2 were taken for the present study. The plasmid profiling of these cultures were evaluated after every subculturing. It was observed from plasmid profiling that both characters i.e. lactose utilization and protein degradation characters were plasmid encoded.