Function of sahH gene in exopolysaccharides synthesis of Streptococcus mutans LuxS null strain / 上海交通大学学报（医学版）

ABSTRACT

Objective·To investigate the function of sahH gene in exopolysaccharides synthesis of Streptococcus mutans LuxS null strain. Methods·sahH+luxS-SmUA159 was constructed by introducing sahH gene into Streptococcus mutans LuxS null strain,while PIB169+luxS-SmUA159 and its wild strain SmUA159 were used as vector control and blank control. Real-time qPCR and anthrone test were performed to investigate the differences in exopolysaccharides synthesis among sahH+luxS-SmUA159, PIB169+luxS-SmUA159 and the wide-type strain SmUA159. Results·The transcriptional levels of gtfA and gtfD were upregulated in the sahH+luxS-SmUA159,compared to SmUA159 and PIB169+luxS-SmUA159(both P<0.05),but there was no statistical difference in the transcriptional levels of gtfB and gtfC.The results of the anthrone test showed exopolysaccharides synthesis of the three groups was also similar. Conclusion·sahH gene affects the expression of some genes related to exopolysaccharides synthesis,but it has little effect on the whole content of bacterial exopolysaccharides.