title: Chimeric adaptor proteins translocate diverse type VI secretion system effectors in Vibrio cholerae.
abstract: Vibrio cholerae is a diverse species of Gram-negative bacteria, commonly found in the aquatic environment and the causative agent of the potentially deadly disease cholera. These bacteria employ a type VI secretion system (T6SS) when they encounter prokaryotic and eukaryotic competitors. This contractile puncturing device translocates a set of effector proteins into neighboring cells. Translocated effectors are toxic unless the targeted cell produces immunity proteins that bind and deactivate incoming effectors. Comparison of multiple V. cholerae strains indicates that effectors are encoded in T6SS effector modules on mobile genetic elements. We identified a diverse group of chimeric T6SS adaptor proteins required for the translocation of diverse effectors encoded in modules. An example for a T6SS effector that requires T6SS adaptor protein 1 (Tap-1) is TseL found in pandemic V. cholerae O1 serogroup strains and other clinical isolates. We propose a model in which Tap-1 is required for loading TseL onto the secretion apparatus. After T6SS-mediated TseL export is completed, Tap-1 is retained in the bacterial cell to load other T6SS machines.
authors.affiliation: Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Unterweger
authors.affiliation: Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Kostiuk
authors.affiliation: Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.
authors.forename: Rina
authors.initials: R
authors.lastname: Ötjengerdes
authors.affiliation: Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.
authors.forename: Ashley
authors.initials: A
authors.lastname: Wilton
authors.affiliation: Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.
authors.forename: Laura
authors.initials: L
authors.lastname: Diaz-Satizabal
authors.affiliation: Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada spukatzki@ualberta.ca.
authors.forename: Stefan
authors.initials: S
authors.lastname: Pukatzki
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D058947:Bacterial Secretion Systems / Q000235:genetics*; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D020071:Interspersed Repetitive Sequences; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D014734:Vibrio cholerae / Q000235:genetics / Q000378:metabolism*; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems; D001427:Bacterial Toxins; D026901:Membrane Transport Proteins; D037521:Virulence Factors
keywords: T6SS; Vibrio cholerae; adaptor protein; compatibility groups; type VI secretion system