口腔微生态中变异链球菌密度感应系统信号传导的研究进展

口腔微生态环境是由许多微生物组成,这些细菌长期在口腔内定居、生长繁殖、不断地进行竞争和拮抗,其间竞争主要是靠密度感应系统.细菌在微生态环境中达到一定浓度后,就产生调控性胞外化学信号,当这些信号分子的浓度达到一定数量值时,菌内的靶基因或者相关基因就被激活,或被抑制.通过这些信号可以调控细菌的一些功能基因,例如形成生物膜、产生细菌素、孢子、产酸、毒力反应等,从而增强细菌的生存力.龋病主要的致龋菌是变异链球菌,变异链球菌可以通过密度感应系统根据周围环境的变化来进行自身调节,以便更好的生存.现将变异链球菌密度感应信号传导的研究进展作一综述.

Advances in the study of signal transmission of Quorum Sensing of Streptococcus Mutans in oral micro-ecological niche

Oral micro- ecological niche is composed of many kinds of microorganism, which inhabit ,grow and multiply,compote and inhibit with each other by the Quorum Sensing in the oral cavity. When bacteria in the micro -ecological environment reach a certain concentration, they can yield extracellular regulative chemical signals. With those signaling molecules accumulating to a certain amount, the expression of target genes will be escalated or inhibited. Moreover, signaling molecules can regulate some functional genes which are closely related with biofilm formation, bacteriocin synthesis, spore production, acid secretion, virulence reaction and so on, thereby improving the viability of bacteria. Streptococcus Mutans, one of the most important pathogen in dental caries development, can also regulate themselves through Quorum Sensing according to the change of the surrounding environment, to survive and thrive. In this review, we summarize the researches on the signal transmission of Quorum Sensing in Streptococcus Mutans.