细菌QS系统LuxS功能研究进展

Current status on function of bacterial LuxS in quorum sensing system-A

群感效应(Quorum sensing,QS)是细菌细胞间利用可扩散的小分子物质进行信息交流的过程,以响应群体密度从而产生各种各样的协调性行为。在革兰氏阳性菌与阴性菌中同时存在的唯一一个QS系统就是涉及自诱导物-2(Autoinducer-2,AI-2)的合成机制。AI-2合成酶LuxS广泛存在于细菌中,说明AI-2是细菌种间交流的语言。然而,LuxS本身也是活性甲基循环(Activated methyl cycle,AMC)的固有组分。近几年来,人们对基于LuxS的QS系统进行了广泛地研究,发现LuxS的功能更加复杂多样。本研究综述了近年来细菌(尤其是病原菌)LuxS在QS系统中的功能,尤其在自诱导物-3(AI-3)的合成、Ⅲ型分泌系统的激活以及病原菌与宿主之间的交叉通讯(Cross-talk)等方面进行了综述,旨在进一步了解细菌信息交流的本质,为病原菌感染的预防及新型抗菌药物的研制提供理论指导。

Quorum sens!ng is a process, during which bacteria cells make use of some small diffisible molecules to communicate and coordinate diverse behaviors in response to cell density. The only QS system existed in both Grampositive and Gram-negative bacteria associates the production of autoinducer-2（AI-2）. The synthase of AI-2, LuxS, is widely distributed among the bacteria,which suggests that AI-2 be a language for interspecies communication. However,LuxS is also an integral component of the activated methyl cycle in bacteria. Recently,LuxS-based QS system has been intensively studied and the results showed that the function of LuxS is various. We summarized the function of bacterial LuxS in QS system in the recent years, especially in the synthesis of AI-3 （a novel autoindueer）, the activation of type 3 secretion system（T3SS） ,and the cross-talk between pathogens and hosts, in order to understand further bacterial communication and offer a strategy for the development of novel antimicrobial drugs.