title: The PagN protein of Salmonella enterica serovar Typhimurium is an adhesin and invasin.
abstract: BACKGROUND
  The pagN gene of Salmonella enterica serovar Typhimurium is a PhoP-regulated gene that is up-regulated during growth within macrophages and in vivo in murine models of infection. The PagN protein displays similarity to the Hek and Tia invasins/adhesins of Escherichia coli. Thus far no function has been ascribed to the PagN protein.
  
  
  RESULTS
  Here we show that the outer membrane located PagN protein mediates agglutination of red blood cells and that this can be masked by LPS. When expressed in Escherichia coli the PagN protein supports adhesion to and invasion of mammalian cells in a manner that is dependent on cytoskeletal rearrangements. S. enterica sv Typhimurium pagN mutants display a reduction in adhesion to and invasion of epithelial cells. Finally, we demonstrate that over-expression of PagN in a SPI-1 mutant can partially compensate for the lack of a functional invasasome.
  
  
  CONCLUSIONS
  PagN is an outer membrane protein that may contribute to the virulence of S. Typhimurium. This protein is a haemagglutinin and contributes to the adherence to mammalian cells. In addition, PagN can mediate high-level invasion of CHO-K1 cells. Previously,pagN mutants have been shown to be less competitive in vivo and thus this may be due to their lessened ability to interact with mammalian cells. Finally PagN can be added to an ever-growing repertoire of factors that contribute to the pathogenesis of Salmonella.
authors.affiliation: Department of Clinical Microbiology, Trinity College Dublin, St James's Hospital, Dublin 8, Ireland. malamber79@gmail.com
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Lambert
authors.forename: Stephen G J
authors.initials: SG
authors.lastname: Smith
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D019073:HT29 Cells; D006388:Hemagglutinins / Q000378:metabolism; D006801:Humans; D009154:Mutation; D011506:Proteins / Q000378:metabolism; D012486:Salmonella typhimurium / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity
chemical_list: D018829:Adhesins, Bacterial; D006388:Hemagglutinins; D011506:Proteins; C015007:autoagglutinin
references.citation: Mol Microbiol. 2004 Jan;51(1):215-25
references.pmid: 14651623
references.citation: Cell Microbiol. 2008 Mar;10(3):576-82
references.pmid: 18182085
references.citation: Expert Rev Mol Med. 2007 Jul 02;9(18):1-17
references.pmid: 17605831
references.citation: Gene. 1984 Sep;29(3):303-13
references.pmid: 6237955
references.citation: J Clin Invest. 1992 Sep;90(3):953-64
references.pmid: 1522243
references.citation: Infect Immun. 1996 May;64(5):1862-5
references.pmid: 8613405
references.citation: Infect Immun. 2005 Jan;73(1):146-54
references.pmid: 15618149
references.citation: Mol Microbiol. 2003 Jan;47(1):103-18
references.pmid: 12492857
references.citation: Gene. 1988 Sep 30;69(2):301-15
references.pmid: 3069586
references.citation: Infect Immun. 2002 Mar;70(3):1530-7
references.pmid: 11854241
references.citation: J Bacteriol. 1978 Jun;134(3):1141-56
references.pmid: 149110
references.citation: Nature. 1970 Aug 15;227(5259):680-5
references.pmid: 5432063
references.citation: FEMS Microbiol Lett. 2007 Apr;269(2):248-55
references.pmid: 17241243
references.citation: Nucleic Acids Res. 2000 Nov 15;28(22):E97
references.pmid: 11071951
references.citation: Biotechnology. 1988;10:5-41
references.pmid: 3061523
references.citation: Proc Natl Acad Sci U S A. 1981 Oct;78(10):6038-42
references.pmid: 6273842
references.citation: J Bacteriol. 1999 Feb;181(3):799-807
references.pmid: 9922242
references.citation: Mol Microbiol. 1999 Aug;33(3):612-22
references.pmid: 10417651
references.citation: Infect Immun. 1994 Nov;62(11):5183-6
references.pmid: 7927803
references.citation: J Biol Chem. 2001 Mar 23;276(12):9083-92
references.pmid: 11108722
references.citation: J Bacteriol. 1992 Jan;174(1):84-91
references.pmid: 1729227
references.citation: Curr Opin Microbiol. 2005 Feb;8(1):10-5
references.pmid: 15694851
references.citation: Methods Enzymol. 1994;235:225-34
references.pmid: 8057896
references.citation: J Biol Chem. 1986 Dec 5;261(34):15974-80
references.pmid: 3023337
references.citation: Infect Immun. 1994 Nov;62(11):5095-101
references.pmid: 7927792
references.citation: Can J Microbiol. 2004 Sep;50(9):719-27
references.pmid: 15644926
references.citation: Proc Natl Acad Sci U S A. 1998 Apr 14;95(8):4641-5
references.pmid: 9539791
references.citation: Mol Immunol. 1989 Nov;26(11):1027-36
references.pmid: 2481821
references.citation: Infect Immun. 2008 Mar;76(3):1135-42
references.pmid: 18160475
references.citation: Infect Immun. 2002 Feb;70(2):953-63
references.pmid: 11796631
references.citation: Infect Immun. 1996 Jun;64(6):2256-65
references.pmid: 8675335
references.citation: J Immunol. 1999 Dec 15;163(12):6718-24
references.pmid: 10586069
references.citation: Proc Natl Acad Sci U S A. 1997 Feb 4;94(3):934-9
references.pmid: 9023360
references.citation: Res Microbiol. 2002 Oct;153(8):537-45
references.pmid: 12437215
references.citation: Nucleic Acids Res. 1988 Jul 11;16(13):6127-45
references.pmid: 3041370