title: Vibrio type III effector VPA1380 is related to the cysteine protease domain of large bacterial toxins.
abstract: Vibrio parahaemolyticus is a Gram-negative halophilic bacterium and one of the leading causes of food-borne gastroenteritis. Its genome harbors two Type III Secretion Systems (T3SS1 and T3SS2), but only T3SS2 is required for enterotoxicity seen in animal models. Effector proteins secreted from T3SS2 have been previously shown to promote colonization of the intestinal epithelium, invasion of host cells, and destruction of the epithelial monolayer. In this study, we identify VPA1380, a T3SS2 effector protein that is toxic when expressed in yeast. Bioinformatic analyses revealed that VPA1380 is highly similar to the inositol hexakisphosphate (IP6)-inducible cysteine protease domains of several large bacterial toxins. Mutations in conserved catalytic residues and residues in the putative IP6-binding pocket abolished toxicity in yeast. Furthermore, VPA1380 was not toxic in IP6 deficient yeast cells. Therefore, our findings suggest that VPA1380 is a cysteine protease that requires IP6 as an activator.
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America.
authors.forename: Thomas
authors.initials: T
authors.lastname: Calder
authors.affiliation: Department of Biophysics and Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America.
authors.forename: Lisa N
authors.initials: LN
authors.lastname: Kinch
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America.
authors.forename: Jessie
authors.initials: J
authors.lastname: Fernandez
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America.
authors.forename: Dor
authors.initials: D
authors.lastname: Salomon
authors.affiliation: Department of Biophysics and Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America; Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America.
authors.forename: Nick V
authors.initials: NV
authors.lastname: Grishin
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America.
authors.forename: Kim
authors.initials: K
authors.lastname: Orth
mesh_terms: D058947:Bacterial Secretion Systems / Q000502:physiology*; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics; D057056:Cysteine Proteases / Q000096:biosynthesis / Q000235:genetics; D020536:Enzyme Activators / Q000378:metabolism*; D015870:Gene Expression; D010833:Phytic Acid / Q000378:metabolism*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D014736:Vibrio parahaemolyticus / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity
chemical_list: D058947:Bacterial Secretion Systems; D001427:Bacterial Toxins; D020536:Enzyme Activators; D011994:Recombinant Proteins; D010833:Phytic Acid; D057056:Cysteine Proteases
references.citation: Cell Rep. 2012 May 31;1(5):453-60
references.pmid: 22787576
references.citation: J Med Invest. 2010 Aug;57(3-4):179-82
references.pmid: 20847516
references.citation: PLoS Pathog. 2012;8(3):e1002593
references.pmid: 22438811
references.citation: Microbiology (Reading). 2012 Nov;158(Pt 11):2859-2869
references.pmid: 22977090
references.citation: PLoS Pathog. 2008 Jan;4(1):e9
references.pmid: 18208325
references.citation: Mol Plant Microbe Interact. 2011 Mar;24(3):305-14
references.pmid: 21062109
references.citation: Infect Immun. 2010 Nov;78(11):4551-9
references.pmid: 20823199
references.citation: J Biol Chem. 2008 Aug 29;283(35):23656-64
references.pmid: 18591243
references.citation: Lancet. 2003 Mar 1;361(9359):743-9
references.pmid: 12620739
references.citation: PLoS One. 2013;8(2):e57558
references.pmid: 23469023
references.citation: Mol Microbiol. 2006 Sep;61(6):1485-96
references.pmid: 16968222
references.citation: Microbiol Immunol. 2004;48(4):313-8
references.pmid: 15107542
references.citation: Microbes Infect. 2011 Nov;13(12-13):992-1001
references.pmid: 21782964
references.citation: J Infect Dis. 2000 May;181(5):1661-6
references.pmid: 10823766
references.citation: Cell Rep. 2013 May 30;3(5):1690-702
references.pmid: 23623501
references.citation: J Biol Chem. 2009 Sep 25;284(39):26557-68
references.pmid: 19620709
references.citation: PLoS One. 2013 Apr 16;8(4):e61086
references.pmid: 23613791
references.citation: Nucleic Acids Res. 2008 Jul 1;36(Web Server issue):W197-201
references.pmid: 18463136
references.citation: Nucleic Acids Res. 2005 Jul 1;33(Web Server issue):W244-8
references.pmid: 15980461
references.citation: Nat Commun. 2013;4:2973
references.pmid: 24346350
references.citation: Mol Microbiol. 2009 Jan;71(2):350-68
references.pmid: 19017275
references.citation: PLoS Pathog. 2010 Jul 08;6(7):e1000942
references.pmid: 20628577
references.citation: J Vis Exp. 2010 Mar 30;(37):
references.pmid: 20354502
references.citation: Nature. 2006 Nov 30;444(7119):567-73
references.pmid: 17136086
references.citation: Proc Natl Acad Sci U S A. 2000 Aug 15;97(17):9431-6
references.pmid: 10920208
references.citation: Nature. 2007 Mar 22;446(7134):415-9
references.pmid: 17334356
references.citation: Food Microbiol. 2007 Sep;24(6):549-58
references.pmid: 17418305
references.citation: Proc Natl Acad Sci U S A. 2007 Oct 23;104(43):17117-22
references.pmid: 17942696
references.citation: J Biol Chem. 2009 Aug 14;284(33):21934-21940
references.pmid: 19553670
references.citation: Science. 2008 Oct 10;322(5899):265-8
references.pmid: 18845756
references.citation: Science. 1999 Jul 2;285(5424):96-100
references.pmid: 10390371
references.citation: Cell Host Microbe. 2011 Oct 20;10(4):401-9
references.pmid: 22018240
references.citation: Cell Host Microbe. 2013 Sep 11;14(3):269-79
references.pmid: 24034613
references.citation: J Biol Chem. 2004 Dec 10;279(50):51953-7
references.pmid: 15459200
references.citation: Science. 2005 Apr 22;308(5721):548-50
references.pmid: 15746386
references.citation: Nucleic Acids Res. 1997 Sep 1;25(17):3389-402
references.pmid: 9254694
references.citation: Infect Immun. 2004 Nov;72(11):6659-65
references.pmid: 15501799
references.citation: PLoS One. 2010 Oct 13;5(10):e13365
references.pmid: 20967223
references.citation: Cell Microbiol. 2009 Apr;11(4):661-77
references.pmid: 19134119
references.citation: Methods Mol Biol. 2014;1079:263-71
references.pmid: 24170408
references.citation: PLoS Pathog. 2008 Nov;4(11):e1000228
references.pmid: 19043560
references.citation: J Biol Chem. 2009 Feb 6;284(6):3389-95
references.pmid: 19047051
references.citation: Clin Microbiol Rev. 2007 Jan;20(1):39-48
references.pmid: 17223622
references.citation: Cell Microbiol. 2014 Jun;16(6):938-47
references.pmid: 24345190