Bröms Jeanette E, Sundin Charlotta, Francis Matthew S, Forsberg Ake
Department of Molecular Biology, Umeå University, Umeå, Sweden.
J Infect Dis. 2003 Jul 15;188(2):239-49. doi: 10.1086/376452. Epub 2003 Jul 1.
The homologues LcrV of Yersinia species and PcrV of Pseudomonas aeruginosa are pore-forming components. When expressed in a Yersinia lcrV background, PcrV formed smaller pores in infected erythrocyte membranes, correlating to a lowered translocation of Yersinia effectors. To understand this phenomenon, cytotoxins exoenzyme S of P. aeruginosa and YopE of Yersinia were introduced into a Yersinia background without Yop effectors but expressing LcrV or PcrV. Comparable translocation of each substrate indicated that substrate recognition by LcrV/PcrV is not a regulator of translocation. Yersinia harboring pcrV coexpressed with its native operon efficiently translocated effectors into HeLa cell monolayers and formed large LcrV-like pores in erythrocyte membranes. Thus, a PcrV complex with native P. aeruginosa translocon components is required to form fully functional pores for complete complementation of effector translocation in Yersinia.
耶尔森菌属的同源物LcrV和铜绿假单胞菌的PcrV是成孔成分。当在耶尔森菌lcrV背景中表达时，PcrV在受感染的红细胞膜上形成较小的孔，这与耶尔森菌效应蛋白的转位降低相关。为了解这一现象，将铜绿假单胞菌的细胞毒素外酶S和耶尔森菌的YopE引入没有Yop效应蛋白但表达LcrV或PcrV的耶尔森菌背景中。每种底物的可比转位表明，LcrV/PcrV对底物的识别不是转位的调节因子。携带pcrV并与其天然操纵子共表达的耶尔森菌能有效地将效应蛋白转运到HeLa细胞单层中，并在红细胞膜上形成类似LcrV的大孔。因此，需要一个与铜绿假单胞菌天然转运体成分结合的PcrV复合物来形成功能完整的孔，以完全补充耶尔森菌中效应蛋白的转位。
