Type VI secretion requires a dynamic contractile phage tail-like structure.
Type VI secretion requires a dynamic contractile phage tail-like structure.
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DOI：
10.1038/nature10846
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发表时间：
2012-02-26
期刊：
影响因子：
64.8
通讯作者：
Mekalanos JJ
中科院分区：
文献类型：
--
作者：
Basler M;Pilhofer M;Henderson GP;Jensen GJ;Mekalanos JJ
VI型分泌系统(T6SS)是一种与细菌毒力相关的纳米机器，由与噬菌体尾部成分进化相关的蛋白质组成。在这里，我们表明，霍乱弧菌T6SS的蛋白质分泌需要一个动态的细胞内小管结构的作用，该结构在结构和功能上与可收缩的噬菌体尾鞘相同。延时荧光显微镜显示，T6SS鞘在组装、快速收缩、拆解和重新组装之间循环。全细胞电子冷冻断层扫描进一步显示，T6SS鞘呈长管状结构，呈伸展或收缩的构象，通过明显的基底层结构与内膜相连。这些数据支持一种模型，在该模型中，T6SS鞘的收缩提供了将蛋白质从效应细胞转移到邻近靶细胞所需的能量。
Type VI Secretion Systems (T6SS) are bacterial virulence-associated nanomachines composed of proteins that are evolutionarily related to components of bacteriophage tails. Here we show that protein secretion by the T6SS of Vibrio cholerae requires the action of a dynamic intracellular tubular structure that is structurally and functionally homologous to contractile phage tail sheath. Time-lapse fluorescence light microscopy revealed that T6SS sheaths cycle between assembly, quick contraction, disassembly and re-assembly. Whole-cell electron cryotomography further showed that T6SS sheaths appear as long tubular structures in either extended or contracted conformations that are connected to the inner membrane by a distinct basal structure. These data support a model in which the contraction of the T6SS sheath provides the energy needed to translocate proteins out of effector cells and into adjacent target cells.