铜绿假单胞菌中群体感应系统研究进展

The Progress of Quorum Sensing System in Pseudomonas aeruginosa

摘要:

群体感应系统(Quorum-sensing system, QS)是一个依赖于细胞数量的基因调控系统。系统中的自诱导物(Autoinducer 或AI)随细胞的数量增加而变化, 当细胞数达到一定数量时, 系统中的自诱导物达到一定的域值时可以与一类转录调节蛋白结合, 开始诱导或抑制数量众多的基因表达, 使细菌表现多细胞特性的群体行为。同时, 群体感应系统受到许多外界环境因素的影响, 其调节途径是一个极其复杂的级联过程。此外, 以群体感应系统为药物靶点来筛选新型抗菌药物越来越受到人们的重视。结合作者本人的工作及铜绿假单胞菌中群体感应系统的最新研究进展, 对该系统在铜绿假单胞菌中的作用及其调控途径进行分析、探讨和总结。

Abstract:

Quorum-sensing system is the gene regulation system depending on the population concentrations. A number of different types of QS systems have been discovered. However, a unifying theme is the synthesis of a small signal molecule, often called an autoinducer or pheromone. These systems regulate the expression of a number of genes synchronously across the bacterial population. When an autoinducer accumulates to the threshold concentration in a population density manner, the expression triggers induction or repression of certain sets of genes that co-ordinate the behavior of the bacterial population, including the expression of virulence factors. In addition, the expression of quorum sensing system is influenced by environmental factors. Quorum sensing in P. aeruginosa consists of a complex network. Based on the facts that QS regulates such an array of P. aeruginosa factors and that deletion of QS regulators attenuates P. aeruginosa virulence, it is conceivable that QS would be an ideal target for the inhibition of Pseudomonas infections. Therefore, alternative mechanisms for targeting P. aeruginosa have been the focus of much research. In this review, the roles and the regulation mechanisms of quorum sensing in P. aeruginosa has been disscussed based on the author’s own research and the latest literatures.