Role of the luxS quorum-sensing system in biofilm formation and virulence of Staphylococcus epidermidis
Role of the luxS quorum-sensing system in biofilm formation and virulence of Staphylococcus epidermidis
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DOI：
10.1128/iai.74.1.488-496.2006
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发表时间：
2006-01-01
影响因子：
3.1
通讯作者：
Gao, Q
中科院分区：
文献类型：
--
作者：
Xu, L;Li, HL;Gao, Q
由表皮葡萄球菌引起的医院感染以植入性医疗器械上的生物被膜为特征。群体感应调节在许多细菌病原体的生物膜发育过程中起着重要作用。在这里，我们描述了LUXS，这是葡萄球菌中的一个群体感应系统，对生物膜的发育和毒力有重要影响。我们构建了一株形成生物膜的表皮葡萄球菌临床分离株的Delta LuxS突变株，并证明htxS信号在表皮葡萄球菌中具有功能。突变菌株在体外表现出生物膜形成的增加，并在生物膜相关感染的大鼠模型中增强了毒力。遗传互补和添加含有自身诱导物2的培养滤液恢复了野生型的表型，表明LuxS通过基于自身诱导物2分泌的细胞-细胞信号机制抑制了生物膜的形成。突变菌株中生物膜外多糖、胞间粘附素的增加可能是观察到的表型的主要原因。以前已经证明，agr群体感应系统影响生物膜的发育和生物膜相关感染的方式与LuxS相似，尽管是通过不同的因素调节的。我们的研究表明了葡萄球菌生物膜发育的群体感应调节的一般方案，这与在许多其他细菌病原体中观察到的相反。
Nosocomial infections caused by Staphylococcus epidermidis are characterized by biofilm formation on implanted medical devices. Quorum-sensing regulation plays a major role in the biofilm development of many bacterial pathogens. Here, we describe luxS, a quorum-sensing system in staphylococci that has a significant impact on biofilm development and virulence. We constructed an isogenic Delta luxS mutant strain of a biofilm-forming clinical isolate of S. epidermidis and demonstrated that htxS signaling is functional in S. epidermidis. The mutant strain showed increased biofilm formation in vitro and enhanced virulence in a rat model of biofilm-associated infection. Genetic complementation and addition of autoinducer 2-containing culture filtrate restored the wild-type phenotype, demonstrating that luxS repressed biofilm formation through a cell-cell signaling mechanism based on autoinducer 2 secretion. Enhanced production of the biofilm exopolysaccharide polysaccharide intercellular adhesin in the mutant strain is presumably the major cause of the observed phenotype. The agr quorum-sensing system has previously been shown to impact biofilm development and biofilm-associated infection in a way similar to that of luxS, although by regulation of different factors. Our study indicates a general scheme of quorum-sensing regulation of biofilm development in staphylococci, which contrasts with that observed in many other bacterial pathogens.