Persson C, Nordfelth R, Holmström A, Håkansson S, Rosqvist R, Wolf-Watz H
Department of Cell and Molecular Biology, Umeå University, Sweden.
Mol Microbiol. 1995 Oct;18(1):135-50. doi: 10.1111/j.1365-2958.1995.mmi_18010135.x.
YopH is translocated by cell-surface-bound bacteria through the plasma membrane to the cytosol of the HeLa cell. The transfer mechanism is contact dependent and polarizes the translocation to only occur at the contact zone between the bacterium and the target cell. More than 99% of the PTPase activity is associated with the HeLa cells. In contrast to the wild-type strain, the yopBD mutant cannot deliver YopH to the cytosol. Instead YopH is deposited in localized areas in the proximity of cell-associated bacteria. A yopN mutant secretes 40% of the total amount of YopH to the culture medium, suggesting a critical role of YopN in regulation of the polarized translocation. Evidence for a region in YopH important for its translocation through the plasma membrane of the target cell but not for secretion from the pathogen is provided.
YopH 由细胞表面结合的细菌通过质膜转运至 HeLa 细胞的胞质溶胶中。转运机制是接触依赖性的，且使转运极化，仅在细菌与靶细胞之间的接触区发生。超过 99%的蛋白酪氨酸磷酸酶（PTPase）活性与 HeLa 细胞相关。与野生型菌株相比，yopBD 突变体无法将 YopH 递送至胞质溶胶中。相反，YopH 沉积在与细胞相关细菌附近的局部区域。yopN 突变体将 YopH 总量的 40%分泌到培养基中，表明 YopN 在极化转运调节中起关键作用。提供了证据表明 YopH 中存在一个区域，该区域对其通过靶细胞质膜的转运很重要，但对病原体的分泌不重要。
