Tam Vincent C, Serruto Davide, Dziejman Michelle, Brieher William, Mekalanos John J
Department of Microbiology and Molecular Genetics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA.
Cell Host Microbe. 2007 Apr 19;1(2):95-107. doi: 10.1016/j.chom.2007.03.005.
We have previously characterized a non-O1, non-O139 Vibrio cholerae strain, AM-19226, that lacks the known virulence factors but contains components of a type III secretion system (T3SS). In this study, we demonstrated that the T3SS is functional and is required for intestinal colonization in the infant mouse model. We also identified VopF, which is conserved among T3SS-positive V. cholerae strains, as an effector containing both formin homology 1-like (FH1-like) and WASP homology 2 (WH2) domains. Translocation of VopF by V. cholerae or expression by transfection altered the actin cytoskeletal organization of the eukaryotic host cells. In vitro domain analysis indicated that both FH1-like and WH2 domains are required for actin nucleation and polymerization activity. These data correlate with in vivo data, suggesting that VopF-mediated alteration of actin polymerization homeostasis is required for efficient intestinal colonization by T3SS+V. cholerae in the infant mouse model.
我们之前鉴定了一株非O1、非O139霍乱弧菌菌株AM-19226，该菌株缺乏已知的毒力因子，但含有III型分泌系统（T3SS）的组分。在本研究中，我们证明T3SS具有功能，并且在幼鼠模型的肠道定殖中是必需的。我们还鉴定出VopF，它在T3SS阳性霍乱弧菌菌株中保守，是一种含有formin同源1样（FH1样）和WASP同源2（WH2）结构域的效应蛋白。霍乱弧菌对VopF的转运或转染表达改变了真核宿主细胞的肌动蛋白细胞骨架组织。体外结构域分析表明，FH1样和WH2结构域对于肌动蛋白成核和聚合活性都是必需的。这些数据与体内数据相关，表明在幼鼠模型中，T3SS阳性霍乱弧菌高效肠道定殖需要VopF介导的肌动蛋白聚合稳态改变。
