title: OI-57, a genomic island of Escherichia coli O157, is present in other seropathotypes of Shiga toxin-producing E. coli associated with severe human disease.
abstract: Strains of Shiga toxin-producing Escherichia coli (STEC) are a heterogeneous E. coli group that may cause severe disease in humans. STEC have been categorized into seropathotypes (SPTs) based on their phenotypic and molecular characteristics and the clinical features of the associated diseases. SPTs range from A to E, according to a decreasing rank of pathogenicity. To define the virulence gene asset ("virulome") characterizing the highly pathogenic SPTs, we used microarray hybridization to compare the whole genomes of STEC belonging to SPTs B, C, and D with that of STEC O157 (SPT A). The presence of the open reading frames (ORFs) associated with SPTs A and B was subsequently investigated by PCR in a larger panel of STEC and in other E. coli strains. A genomic island termed OI-57 was present in SPTs A and B but not in the other SPTs. OI-57 harbors the putative virulence gene adfO, encoding a factor enhancing the adhesivity of STEC O157, and ckf, encoding a putative killing factor for the bacterial cell. PCR analyses showed that OI-57 was present in its entirety in the majority of the STEC genomes examined, indicating that it represents a stable acquisition of the positive clonal lineages. OI-57 was also present in a high proportion of the human enteropathogenic E. coli genomes assayed, suggesting that it could be involved in the attaching-and-effacing colonization of the intestinal mucosa. In conclusion, OI-57 appears to be part of the virulome of pathogenic STEC and further studies are needed to elucidate its role in the pathogenesis of STEC infections.
authors.affiliation: European Union Reference Laboratory for Escherichia coli, Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare, Rome, Italy.
authors.forename: Lejla
authors.initials: L
authors.lastname: Imamovic
authors.forename: Rosangela
authors.initials: R
authors.lastname: Tozzoli
authors.forename: Valeria
authors.initials: V
authors.lastname: Michelacci
authors.forename: Fabio
authors.initials: F
authors.lastname: Minelli
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Marziano
authors.forename: Alfredo
authors.initials: A
authors.lastname: Caprioli
authors.forename: Stefano
authors.initials: S
authors.lastname: Morabito
mesh_terms: D004927:Escherichia coli Infections / Q000382:microbiology / Q000473:pathology; D019453:Escherichia coli O157 / Q000235:genetics / Q000472:pathogenicity*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D044404:Genomic Islands / Q000235:genetics*; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D016366:Open Reading Frames / Q000235:genetics; D016133:Polymerase Chain Reaction; D012703:Serotyping; D012720:Severity of Illness Index; D054323:Shiga-Toxigenic Escherichia coli / Q000145:classification / Q000235:genetics / Q000472:pathogenicity*; D014774:Virulence / Q000235:genetics
chemical_list: D029968:Escherichia coli Proteins
references.citation: Microbiology (Reading). 2010 Feb;156(Pt 2):408-419
references.pmid: 19892762
references.citation: J Clin Microbiol. 2003 Nov;41(11):4930-40
references.pmid: 14605120
references.citation: Biotechniques. 2003 Feb;34(2):374-8
references.pmid: 12613259
references.citation: Science. 1984 Nov 9;226(4675):694-6
references.pmid: 6387911
references.citation: Lancet. 2005 Mar 19-25;365(9464):1073-86
references.pmid: 15781103
references.citation: Infect Immun. 2008 May;76(5):1858-65
references.pmid: 18316380
references.citation: Trends Microbiol. 2000 Mar;8(3):128-33
references.pmid: 10707066
references.citation: J Clin Microbiol. 2005 Aug;43(8):3840-50
references.pmid: 16081921
references.citation: Microb Drug Resist. 2002 Summer;8(2):85-91
references.pmid: 12118522
references.citation: Vet Res. 2005 May-Jun;36(3):289-311
references.pmid: 15845227
references.citation: J Clin Microbiol. 1994 Oct;32(10):2460-3
references.pmid: 7814482
references.citation: J Bacteriol. 1984 Feb;157(2):690-3
references.pmid: 6363394
references.citation: DNA Res. 2001 Feb 28;8(1):11-22
references.pmid: 11258796
references.citation: J Bacteriol. 2008 Sep;190(17):5832-40
references.pmid: 18586943
references.citation: J Infect Dis. 2005 Oct 15;192(8):1422-9
references.pmid: 16170761
references.citation: Nature. 2001 Jan 25;409(6819):529-33
references.pmid: 11206551
references.citation: Clin Microbiol Rev. 1998 Jan;11(1):142-201
references.pmid: 9457432
references.citation: BMC Microbiol. 2009 Jun 03;9:117
references.pmid: 19490652
references.citation: Proc Natl Acad Sci U S A. 1998 Aug 4;95(16):9413-7
references.pmid: 9689094
references.citation: Infect Immun. 2002 Sep;70(9):5158-66
references.pmid: 12183566
references.citation: Mol Microbiol. 2000 Jan;35(2):275-88
references.pmid: 10652089
references.citation: Infect Immun. 2002 Dec;70(12):6853-9
references.pmid: 12438362
references.citation: Infect Immun. 2000 Jan;68(1):64-71
references.pmid: 10603369
references.citation: Mol Microbiol. 1997 Jan;23(2):399-407
references.pmid: 9044273
references.citation: J Med Microbiol. 1999 Oct;48(10):891-896
references.pmid: 10510965
references.citation: Infect Immun. 2004 Sep;72(9):5402-11
references.pmid: 15322038
references.citation: J Clin Microbiol. 2005 Aug;43(8):4052-6
references.pmid: 16081950
references.citation: Emerg Infect Dis. 1997 Oct-Dec;3(4):578-9
references.pmid: 9366613
references.citation: Infect Immun. 1995 Mar;63(3):1055-61
references.pmid: 7868227
references.citation: J Gastroenterol Hepatol. 2002 Apr;17(4):467-75
references.pmid: 11982729
references.citation: Infect Immun. 2001 Nov;69(11):6660-9
references.pmid: 11598035
references.citation: Emerg Infect Dis. 1997 Oct-Dec;3(4):417-23
references.pmid: 9366592
references.citation: Infect Immun. 2003 Jun;71(6):3343-8
references.pmid: 12761117
references.citation: Int J Med Microbiol. 2007 Feb;297(1):9-15
references.pmid: 17224306
references.citation: Infect Immun. 2000 Apr;68(4):2148-55
references.pmid: 10722613
references.citation: J Clin Microbiol. 2010 Jan;48(1):178-83
references.pmid: 19940059
references.citation: Emerg Infect Dis. 2003 Jan;9(1):106-8
references.pmid: 12533290
references.citation: J Bacteriol. 2008 Jan;190(1):275-85
references.pmid: 17873042