Characterzation and mode of action of purified Rm-10 bacteriocin N-ABC

Abstract

We attempted to oharacterize a purified bacteriocin (N-ABC) isolated from Streptococcus mutans Rm-10. N-ABC was stable to heating at 120℃ for 10 min and under acidic pH conditions. However, the exposure of N-ABC to pH 11.0 resulted in complete loss of the activity. It was partially destroyed with trypsin, pepsin, papain, α-chymotrypsin, β-galactosidase, α-galactosidase and endo-β-galactosidase. The bacteriocin showed a relatively narrow spectrum of activity against Streptococcus mutans strains. N-ABC killed Enterococcus faecalis ODU in a dosedependent manner by a bactericidal mode of action. These results indicate that this bacteriocin is different from two bacteriocins previously reported by Muramatsu.