Lanthionine-containing peptide antibiotic (lantibiotic) active on certain Gram-positive bacteria. The bactericidal activity of lantibiotics is based on depolarization of energized bacterial cytoplasmic membranes, initiated by the formation of aqueous transmembrane pores. Induces its own expression in at least strain M25. Maturation of lantibiotics involves the enzymatic conversion of Thr, and Ser into dehydrated AA and the formation of thioether bonds with cysteine. This is followed by membrane translocation and cleavage of the modified precursor (By similarity). A longer form (streptin 2, with three more amino acids at the N-terminus) is probably due to incomplete processing. Other forms also exist, some of which are due to differing levels of dehydration. Belongs to the type A lantibiotic family.