title: A functional VipA-VipB interaction is required for the type VI secretion system activity of Vibrio cholerae O1 strain A1552.
abstract: BACKGROUND
  Many Gram-negative bacteria rely on a type VI secretion system (T6SS) to infect eukaryotic cells or to compete against other microbes. Common to these systems is the presence of two conserved proteins, in Vibrio cholerae denoted VipA and VipB, which have been shown to interact in many clinically relevant pathogens. In this study, mutagenesis of a defined region within the VipA protein was used to identify residues important for VipB binding in V. cholerae O1 strain A1552.
  
  
  RESULTS
  A dramatically diminished interaction was shown to correlate with a decrease in VipB stability and a loss of hemolysin co-regulated protein (Hcp) secretion and rendered the bacterium unable to compete with Escherichia coli in a competition assay.
  
  
  CONCLUSIONS
  This confirms the biological relevance of the VipA-VipB interaction, which is essential for the T6SS activity of many important human pathogens.
authors: Department of Clinical Microbiology, Clinical Bacteriology, Umeå University, Umeå SE-901 85, Sweden. jeanette.broms@climi.umu.se
authors: Jeanette E
authors: JE
authors: Bröms
authors: Takahiko
authors: T
authors: Ishikawa
authors: Sun N
authors: SN
authors: Wai
authors: Anders
authors: A
authors: Sjöstedt
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D058947:Bacterial Secretion Systems; D004252:DNA Mutational Analysis; D004926:Escherichia coli / Q000254:growth & development; D006801:Humans; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D025941:Protein Interaction Mapping; D041241:Vibrio cholerae O1 / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems; D050505:Mutant Proteins
references: Proc Natl Acad Sci U S A. 2010 Dec 7;107(49):21128-33
references: 21084635
references: PLoS One. 2009 Aug 24;4(8):e6734
references: 19701456
references: Science. 2006 Jun 9;312(5779):1526-30
references: 16763151
references: Annu Rev Genet. 2010;44:71-90
references: 21047256
references: Gene. 1986;48(1):119-31
references: 3549457
references: J Biol Chem. 2010 Nov 12;285(46):35988-98
references: 20729192
references: J Bacteriol. 2009 Apr;191(8):2431-46
references: 19201795
references: Cell. 1987 Jan 30;48(2):271-9
references: 3802195
references: Nature. 2012 Feb 26;483(7388):182-6
references: 22367545
references: Proc Natl Acad Sci U S A. 2010 Mar 2;107(9):4365-70
references: 20150509
references: Infect Immun. 2009 Mar;77(3):935-42
references: 19103773
references: Methods. 2001 Dec;25(4):402-8
references: 11846609
references: Proc Natl Acad Sci U S A. 1987 May;84(9):2833-7
references: 2883655
references: Trends Microbiol. 2010 Dec;18(12):531-7
references: 20961764
references: EMBO J. 2009 Feb 18;28(4):315-25
references: 19131969
references: J Biol Chem. 2011 Aug 26;286(34):30010-21
references: 21733841
references: Mol Microbiol. 2000 Oct;38(1):85-102
references: 11029692
references: Cell Host Microbe. 2009 Mar 19;5(3):234-43
references: 19286133
references: Methods Mol Biol. 2004;261:231-46
references: 15064462
references: EMBO Rep. 2008 Aug;9(8):735-41
references: 18617888
references: PLoS One. 2011;6(8):e23876
references: 21909372
references: PLoS Pathog. 2007 Jun;3(6):e84
references: 17571921
references: Infect Immun. 2012 Feb;80(2):575-84
references: 22083711
references: BMC Genomics. 2009 Mar 12;10:104
references: 19284603
references: Proc Natl Acad Sci U S A. 2006 Jan 31;103(5):1528-33
references: 16432199
references: Proc Natl Acad Sci U S A. 2007 Sep 25;104(39):15508-13
references: 17873062
references: Genetics. 1996 Dec;144(4):1425-36
references: 8978031
references: Mol Microbiol. 2002 Nov;46(4):1183-97
references: 12421321
references: Cell Host Microbe. 2010 Jan 21;7(1):25-37
references: 20114026
references: Curr Opin Microbiol. 2008 Feb;11(1):3-8
references: 18289922
references: PLoS Pathog. 2010 Aug 26;6(8):e1001068
references: 20865170
references: Nature. 2011 Jul 20;475(7356):343-7
references: 21776080
references: Proc Natl Acad Sci U S A. 2005 Aug 2;102(31):11082-7
references: 16043713
references: Cell Host Microbe. 2010 Jul 22;8(1):2-6
references: 20638635
references: Proc Natl Acad Sci U S A. 2010 Nov 9;107(45):19520-4
references: 20974937
references: J Bacteriol. 2011 Nov;193(21):6057-69
references: 21890705
references: Microbiology (Reading). 2008 Jun;154(Pt 6):1570-1583
references: 18524912