Translocation of a Vibrio cholerae type VI secretion effector requires bacterial endocytosis by host cells.

ABSTRACT: The type VI secretion system (T6SS) is a virulence mechanism common to several Gram-negative pathogens. In Vibrio cholerae, VgrG-1 is required for T6SS-dependent secretion. VgrG-1 is also secreted by T6SS and displays a C-terminal actin crosslinking domain (ACD). Using a heterologous reporter enzyme in place of the ACD, we show that the effector and secretion functions of VgrG-1 are genetically dissociable with the ACD being dispensable for secretion but required for T6SS-dependent phenotypes. Furthermore, internalization of bacteria is required for ACD translocation into phagocytic target cells. Inhibiting bacterial uptake abolishes actin crosslinking, while improving intracellular survival enhances it. Otherwise resistant nonphagocytic cells become susceptible to T6SS-mediated actin cros

SUBMITTER: Ma AT 

PROVIDER: S-EPMC3142922 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature