Frequency and expression of nlm and smb genes in streptococcus mutans clinical strains

Streptococcus mutans in the oral cavity has ability to produce bacteriocins (mutacin) by antibiotic properties. Aim of this study was to investigate the frequency and expression of genes encoding mutacins type I, II, III. IV and bsm299, bsm1889 Genes cluster as non putative bacteriocinds Identification of clinical isolates of Streptococcus and presence of genes encoding mutacins was determined by PCR. Antibacterial activities of mutacins were evaluated against indicator strains with diffusion methods (disc and well). A total of 56 samples collected from patients referred to a dental center, 24 strains were identified as Streptococcus mutans that the total 24 strains were able to produce mutacins. 67, 52% of Streptococcus mutans strains had wide a spectrum antimicrobial, 37, 5% of the strains that had a variety of frequency mutacin genes, more inhibitory activite against, respectively, staphylococse epidermidis, Staphylococcus aureus and Enterococcus faecalis. The best inhibitory effects of mutacin against Staphylococcus epidermidis were evaluated (0/0675(.This study showed that The expression frequency of the bsm (putative bacriocins) gene was higher than that of the characterized mutacins (I–IV) today as a major factor produced by Streptococcus mutans is a known anti-microbial. With attention to high persistence of mutacins and also wide antimicrobial against Staphylococcusepidermidis can be used as safe antimicrobial agent in the future in the treatment of superficial infections used.