ExsB is required for correct assembly of the Pseudomonas aeruginosa type III secretion apparatus in the bacterial membrane and full virulence in vivo.
ExsB is required for correct assembly of the Pseudomonas aeruginosa type III secretion apparatus in the bacterial membrane and full virulence in vivo.
复制标题
ExsB 是铜绿假单胞菌 III 型分泌装置在细菌膜中的正确组装和体内充分毒力所必需的。
DOI：
10.1128/iai.00048-15
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发表时间：
2015
影响因子：
3.1
通讯作者：
Perdu C
中科院分区：
文献类型：
--
作者：
Perdu C
铜绿假单胞菌导致囊性纤维化患者的高发病率感染，并且是医院感染的主要病原体。其最有效的毒力因子之一是 III 型分泌系统 (T3SS)，可将毒素直接注入宿主细胞的细胞质中。 ExsB 是一种位于细菌外膜的脂蛋白，是该机制的组成部分之一，但其功能至今仍难以捉摸。 exsB 基因在 exsCEBA 调节基因操纵子中的定位表明其与 T3SS 调节有关，而其与耶尔森氏菌属的 yscW 相似。主张在机械装配中发挥作用。目前的工作表明，ExsB 对于铜绿假单胞菌的完全体内毒力是必需的。此外，使用真核细胞感染和体外测定证明了 ExsB 对最佳 T3SS 组装和活性的要求。特别是，ExsB 促进 T3SS 促胰液素在细菌外膜中的组装，突出了 ExsB 作为 Pilotin 的分子作用。这种参与 T3S 装置组装的调节可能解释了 ExsB 编码基因在调节基因操纵子中的定位。
Pseudomonas aeruginosa is responsible for high-morbidity infections of cystic fibrosis patients and is a major agent of nosocomial infections. One of its most potent virulence factors is a type III secretion system (T3SS) that injects toxins directly into the host cell cytoplasm. ExsB, a lipoprotein localized in the bacterial outer membrane, is one of the components of this machinery, of which the function remained elusive until now. The localization of theexsBgene within theexsCEBAregulatory gene operon suggested an implication in the T3SS regulation, while its similarity withyscWfrom Yersinia spp. argued in favor of a role in machinery assembly. The present work shows that ExsB is necessary for fullin vivovirulence of P. aeruginosa. Furthermore, the requirement of ExsB for optimal T3SS assembly and activity is demonstrated using eukaryotic cell infection andin vitroassays. In particular, ExsB promotes the assembly of the T3SS secretin in the bacterial outer membrane, highlighting the molecular role of ExsB as a pilotin. This involvement in the regulation of the T3S apparatus assembly may explain the localization of the ExsB-encoding gene within the regulatory gene operon.