title: Marker for type VI secretion system effectors.
abstract: Bacteria use diverse mechanisms to kill, manipulate, and compete with other cells. The recently discovered type VI secretion system (T6SS) is widespread in bacterial pathogens and used to deliver virulence effector proteins into target cells. Using comparative proteomics, we identified two previously unidentified T6SS effectors that contained a conserved motif. Bioinformatic analyses revealed that this N-terminal motif, named MIX (marker for type six effectors), is found in numerous polymorphic bacterial proteins that are primarily located in the T6SS genome neighborhood. We demonstrate that several MIX-containing proteins are T6SS effectors and that they are not required for T6SS activity. Thus, we propose that MIX-containing proteins are T6SS effectors. Our findings allow for the identification of numerous uncharacterized T6SS effectors that will undoubtedly lead to the discovery of new biological mechanisms.
authors.affiliation: Department of Molecular Biology.
authors.forename: Dor
authors.initials: D
authors.lastname: Salomon
authors.affiliation: Howard Hughes Medical Institute.
authors.forename: Lisa N
authors.initials: LN
authors.lastname: Kinch
authors.affiliation: Department of Biochemistry, and.
authors.forename: David C
authors.initials: DC
authors.lastname: Trudgian
authors.affiliation: Department of Biochemistry, and.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Guo
authors.affiliation: Department of Molecular Biology.
authors.forename: John A
authors.initials: JA
authors.lastname: Klimko
authors.affiliation: Howard Hughes Medical Institute,Department of Biochemistry, andDepartment of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390-8816.
authors.forename: Nick V
authors.initials: NV
authors.lastname: Grishin
authors.affiliation: Department of Biochemistry, and.
authors.forename: Hamid
authors.initials: H
authors.lastname: Mirzaei
authors.affiliation: Department of Molecular Biology,Department of Biochemistry, and kim.orth@utsouthwestern.edu.
authors.forename: Kim
authors.initials: K
authors.lastname: Orth
mesh_terms: D020816:Amino Acid Motifs; D001419:Bacteria / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D058947:Bacterial Secretion Systems / Q000235:genetics*; D016680:Genome, Bacterial / Q000502:physiology*; D055106:Genome-Wide Association Study
chemical_list: D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems
keywords: bacterial competition; colicin; toxin; vibrio