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Variation in the Genomic islands of porcine enteropathogenic E. coli strains of serogroup O45 revealed by CGH and PCR.

ABSTRACT: Background: Members of E. coli serogroup O45 are porcine enteropathogenic E. coli (PEPEC) strains which cause post-weaning diarrhea and produce characteristic attaching and effacing (A/E) lesions. Most of O45 PEPEC strains possess the locus of enterocyte effacement (LEE), encoding the virulence factors for A/E lesions, and often possess the paa gene, which is thought to contribute to the early stages of PEPEC virulence. Methodology: Nine O45 PEPEC strains and a rabbit enteropathogenic (REPEC) strain, known to produce A/E lesions, were characterized using an E. coli O157-E. coli K12 whole genome microarray and a virulence gene-specific microarray, and by PCR experiments. Results: Based on their virulence genes profiles, the 10 strains were characterized as atypical EPEC. The differences in their genomes pointed to two distinct evolutionary groups of O45 PEPEC, Group I and Group II, and to the contribution these genetic differences have on virulence in pigs. Group I contained the REPEC strain and four O45 PEPEC strains known to induce severe A/E lesions in challenged pigs whereas Group II was composed of five other O45 PEPEC strains which induced less severe or no A/E lesions in challenged pigs. Significant differences between Groups I and II were found in the presence or absence of 50 O-Islands (OIs) or S-loops and 13 K-islands (KIs) or K-loops, including the virulence-associated islands OI#1 (S-loop#1), OI#47 (S-loop#71), OI#57 (S-loop#85), OI#71 (S-loop#108), OI#115, OI#122, and OI#154 (S-loop#253).

ORGANISM(S): Escherichia coli Escherichia coli O157:H7 str. EDL933 Escherichia coli O157:H7 Escherichia coli str. K-12 substr. MG1655 Escherichia coli O157:H7 str. Sakai

PROVIDER: GSE17036 | GEO | 2009/07/11

SECONDARY ACCESSION(S): PRJNA117835

REPOSITORIES: GEO

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Variation in the Genomic islands of porcine enteropathogenic E. coli strains of serogroup O45 revealed by CGH and PCR.

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