OBJECTIVETo observe the dynamic changes of membrane-bound proton-translocating ATPase (F-ATPase) in the development of dental caries, the expression of Streptococcus mutans F-ATPase under different pH concentrations and during the development of dental caries is analyzed.

METHODSStreptococcus mutans cultured under different pH (pH4.0-7.0) concentrations and containing 5% glucose and no glucose containing BHI were collected. RNA was extracted. Subsequently, F-ATPase gene was detected using real-time polymerase chain reaction. Male Wistar rats were divided randomly into caries group and control group. The rats in the caries group were fed caries feed and 5% glucose water, whereas those of control group were fed normal feed. Total RNA was extracted from plaque samples, which were collected from rats' oral cavity every two weeks. F-ATPase gene was detected by real-time PCR. In the 11th week, the upper and lower jaw bone specimens of rats were taken, and molar caries damage assessed.

RESULTSThe expression of F-ATPase in the caries group was higher than that in the control group (P<0.05). In addition, the gene was expressed highest in pH5.0 and the lowest in pH4.0 (P<0.05). 2) The expression of F-ATPase progressively increased during the caries development in both groups; expression in the caries group was higher than that in control group (P<0.05).

CONCLUSIONAcid-resisting viru-lence factor F-ATPase is related closely with the incidence and development of dental caries.