Plasmid-associated bacteriocin production by a Lactobacillus plantarum strain.

A Lactobacillus plantarum strain, LTF154, isolated from a fermented sausage, produces a bacteriocin, designated plantacin 154. Plantacin 154 was stable to heat treatment, and its activity was sensitive to proteolytic enzymes. The molecular mass, as indicated by activity detection after SDS-PAGE, was estimated to be 3.0 kDa or less. A plasmid-curing experiment and transformation analysis indicated that a 9.5-MDa plasmid, pLP1542, may be involved in the production of plantacin 154.