A C-terminal region of Yersinia pestis YscD binds the outer membrane secretin YscC.
A C-terminal region of Yersinia pestis YscD binds the outer membrane secretin YscC.
复制标题
鼠疫耶尔森氏菌 YscD 的 C 末端区域结合外膜分泌素 YscC。
DOI：
10.1128/jb.01137-10
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发表时间：
2011
影响因子：
3.2
通讯作者：
Plano,GregoryV
中科院分区：
文献类型：
--
作者：
Ross,JuliaA;Plano,GregoryV
YscD 是鼠疫耶尔森菌质粒 pCD1 编码的 III 型分泌系统 (T3SS) 的重要组成部分。 YscD 具有单个跨膜 (TM) 结构域，可将较小的 N 末端细胞质区域（残基 1 至 121）连接到较大的周质区域（残基 143 至 419）。删除分析证实，N 端细胞质区域和 C 端周质区域都是 YscD 功能所必需的。较小的靶向删除表明，预测的细胞质叉头相关 (FHA) 结构域也是组装功能性 T3SS 所必需的；相反，YscD 的预测周质磷脂结合 (BON) 结构域和假定的周质“环构建基序”结构域可以被删除，而对 T3S 过程没有显着影响。尽管删除假定的“造环基序”结构域本身并没有破坏 T3S 活性，但 T3S 装置的钙依赖性调节受到影响。 YscD 的极端 C 末端区域（残基 354 至 419）对于分泌活性至关重要，并且当输出到野生型亲本菌株的周质时，对 T3S 过程具有强烈的显性负效应。免疫共沉淀研究表明，YscD 的该区域介导 YscD 与外膜 YscC 促胰液素复合物的相互作用。最后，用不同序列的TM结构域替换YscD TM结构域对T3S过程没有影响，表明TM结构域在T3SS的组装或功能中不具有序列特异性功能。
YscD is an essential component of the plasmid pCD1-encoded type III secretion system (T3SS) of Yersinia pestis. YscD has a single transmembrane (TM) domain that connects a small N-terminal cytoplasmic region (residues 1 to 121) to a larger periplasmic region (residues 143 to 419). Deletion analyses established that both the N-terminal cytoplasmic region and the C-terminal periplasmic region are required for YscD function. Smaller targeted deletions demonstrated that a predicted cytoplasmic forkhead-associated (FHA) domain is also required to assemble a functional T3SS; in contrast, a predicted periplasmic phospholipid binding (BON) domain and a putative periplasmic “ring-building motif” domain of YscD could be deleted with no significant effect on the T3S process. Although deletion of the putative “ring-building motif” domain did not disrupt T3S activity per se, the calcium-dependent regulation of the T3S apparatus was affected. The extreme C-terminal region of YscD (residues 354 to 419) was essential for secretion activity and had a strong dominant-negative effect on the T3S process when exported to the periplasm of the wild-type parent strain. Coimmunoprecipitation studies demonstrated that this region of YscD mediates the interaction of YscD with the outer membrane YscC secretin complex. Finally, replacement of the YscD TM domain with a TM domain of dissimilar sequence had no effect on the T3S process, indicating that the TM domain has no sequence-specific function in the assembly or function of the T3SS.