RESUMEN
PURPOSE: To analyze the effect of ffh gene silencing on the aciduricity of fluoride resistant Streptococcus mutans in vitro. METHODS: By using electroporation, UA159-FR was transformed and combined with targeted site of ffh gene sequence, and the best piece of siRNA for fluoride resistant Streptococcus mutans was screened. In different values of pH of BHI, they were cultured for 24 hours with UA159-FR respectively, and then centrifugated to determine the pH and OD600. SPSS17.0 software package was used to analyze the data. RESULTS: The aciduricity of UA159-FR had significant differences compared with ffh gene silencing for UA159-FR in δpH (P<0.05), and the former was higher than the latter. At pH=3.5-5.0, P<0.01; at pH=5.5-7.5, P<0.05. Significant differences were noted in OD600 and their growth tendency were similar. CONCLUSIONS: The aciduricity of fluoride resistant Streptococcus mutans has significant effect when the ffh gene is silenced.