Targeting of Yersinia Yop proteins into the cytosol of HeLa cells:: one-step translocation of YopE across bacterial and eukaryotic membranes is dependent on SycE chaperone
Targeting of Yersinia Yop proteins into the cytosol of HeLa cells:: one-step translocation of YopE across bacterial and eukaryotic membranes is dependent on SycE chaperone
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DOI：
10.1046/j.1365-2958.1998.00822.x
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发表时间：
1998-05-01
影响因子：
3.6
通讯作者：
Schneewind, O
中科院分区：
文献类型：
--
作者：
Lee, VT;Anderson, DM;Schneewind, O
致病性耶尔森氏菌通过将它们的一些Yop蛋白靶向到真核细胞胞质溶胶中来粘附并杀死巨噬细胞。关于YopE靶向是作为多肽在细胞之间的直接易位还是在两个不同的步骤中进行存在争议，每个步骤都需要用于YopE分泌穿过细菌包膜和易位到真核细胞胞质溶胶中的特异性信号。在这里，我们使用了选择性溶解的真核细胞质膜与毛地黄皂苷测量Yop靶向耶尔森氏菌感染的HeLa细胞。YopE、YopH、YopM和YopN存在于真核细胞胞质中，而不在细胞外培养基中。当结合到耶尔森氏菌细胞质中的SycE分子伴侣时，YopE残基1-100对于杂合新霉素磷酸转移酶的靶向是必需的和足够的。电子显微镜分析未能检测到YopE靶向的细胞外中间体，表明一步易位机制。
Pathogenic Yersiniae adhere to and kill macrophages by targeting some of their Yop proteins into the eukaryotic cytosol. There is debate about whether YopE targeting proceeds as a direct translocation of polypeptide between cells or in two distinct steps, each requiring specific signals for YopE secretion across the bacterial envelope and for translocation into the eukaryotic cytosol. Here, we used the selective solubilization of the eukaryotic plasma membrane with digitonin to measure Yop targeting during Yersinia infections of HeLa cells. YopE, YopH, YopM and YopN were found in the eukaryotic cytosol but not in the extracellular medium. When bound to SycE chaperone in the Yersinia cytoplasm, YopE residues 1-100 are necessary and sufficient for the targeting of hybrid neomycin phosphotransferase. Electron microscopic analysis failed to detect an extracellular intermediate of YopE targeting, suggesting a one-step translocation mechanism.