RESUMEN
Streptococcus mutans, resident in the oral cavity, is able to produce bacteriocins with antimicrobial properties, called mutacins. Aim of this study was to investigate the antagonistic properties of these bacteria isolated from Iranian patients. Antibacterial activities of mutacins were evaluated against S. mutans ATCC 35668 with disc diffusion and genes encoding mutacin types I, II and III was determined by PCR amplification method. Of 32 S. mutans isolated from caries-active and caries-free individuals, 25 strains demonstrated antimicrobial repertoire and 67.2% showed positive genotypes by PCR. This study showed that mutacins of Streptococcus mutans have antagonistic effects on the growth of other bacteria. Extract of this component could be used as antibacterial drug