ABSTRACT
Objective:To investigate the relationship between ciaH, eno, pykF genes and fluoride resistance through determining the differential expressions of ciaH, eno and pykF genes of fluoride-resistant Streptococcus mutans cultivated in fluoride environment. Methods:The cultured Streptococcus mutans and their fluoride-resistant strains were divided into UA (Streptococcus mutans subcultured in BHI without NaF), FR (fluoride-resistant Streptococcus mutans subcultured in BHI without NaF) and FFR (fluoride-resistant Streptococcus mutans subcultured in BHI containing 1 g·L-1 NaF) groups.After 11 h (logarithmic phase) and 20 h (platform stage) cultivation, the expression levels of ciaH, eno and pykF mRNA were detected by RT-PCR method.Results:Compared with FR group, the expression levels of ciaH, eno and pykF mRNA in FFR group were increased both in the logarithmic phase and the platform stage(P0.05), but it was increased in the platform stage (P<0.01).Conclusion:Fluoride can increase the expression levels of ciaH, eno and pykF genes in fluoride-resistant Streptococcus mutans, indicating that these genes are related to the production of fluoride resistance.