The YopB protein of Yersinia pseudotuberculosis is essential for the translocation of Yop effector proteins across the target cell plasma membrane and displays a contact-dependent membrane disrupting activity

摘要: During infection of cultured epithelial cells, surface-located Yersinia pseudotuberculosis deliver Yop (Yersinia outer protein) virulence factors into the cytoplasm target cell. A non-polar yopB mutant strain displays a wild-type phenotype with respect to in vitro regulation and secretion but fails elicit cytotoxic response HeLa cells is unable inhibit phagocytosis by macrophage-like J774 cells. Additionally, was avirulent mouse model. No YopE or YopH protein were observed within infected strain, suggesting that loss due its inability translocate effector proteins through cell plasma membrane. Expression YopB necessary for Yersinia-induced lysis sheep erythrocytes. Purified shown have membrane disruptive activity vitro. YopB-dependent haemolytic required contact between bacteria erythrocytes could be inhibited high, not low, molecular weight carbohydrates. Similarly, expression reduced activity. Therefore, we propose essential formation pore cell-to-cell transfer proteins.