Bacteriocin from Bacillus megaterium ATCC 19213: Comparative studies with megacin A-216

Abstract

A bacteriocin produced by Bacillus megaterium ATCC 19213 was identified, purified, and compared with megacin A from B. megaterium 216. The ATCC 19213 bacteriocin was inducible with mitomycin C and showed phospholipase A activity. Both megacin A-216 and megacin A-19213 contained two dissimilar polypeptide subunits. Megacin A-216 contains a 30,000-dalton α subunit and a 15,000-dalton β subunit. MegacinA-19213 is composed of an α subunit 18,000 daltons in mass and a β subunit about 7,500 daltons in mass. No sequence similarities between α and β subunits of either megacin were detected. The two megacins were further distinguished by quantitative differences in activity spectra and by immunodiffusion analyses.