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Draft genome sequences of six Escherichia coli isolates from the stepwise model of emergence of Escherichia coli O157:H7.

ABSTRACT: Enterohemorrhagic Escherichia coli (EHEC) of serotype O157:H7 has been implicated in food-borne illnesses worldwide. An evolutionary model was proposed in which the highly pathogenic EHEC O157:H7 serotype arose from its ancestor, enteropathogenic E. coli (EPEC) O55:H7 (sorbitol fermenting [SOR(+)] and ?-glucuronidase positive [GUD(+)]), through sequential gain of virulence, phenotypic traits, and serotype change. Here we report six draft genomes of strains belonging to this evolutionary model: two EPEC O55:H7 (SOR(+) GUD(+)) strains, two nonmotile EHEC O157:H(-) strains (SOR(+) GUD(+)) containing plasmid pSFO157, one EHEC O157:H7 (SOR(-) GUD(+)) strain, and one O157:H7 strain containing plasmid pSFO157 (SOR(+) GUD(+)).

SUBMITTER: Rump LV

PROVIDER: S-EPMC3133052 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Draft genome sequences of six Escherichia coli isolates from the stepwise model of emergence of Escherichia coli O157:H7.

Rump L V LV Strain E A EA Cao G G Allard M W MW Fischer M M Brown E W EW Gonzalez-Escalona N N

Journal of bacteriology 20110211 8

Enterohemorrhagic Escherichia coli (EHEC) of serotype O157:H7 has been implicated in food-borne illnesses worldwide. An evolutionary model was proposed in which the highly pathogenic EHEC O157:H7 serotype arose from its ancestor, enteropathogenic E. coli (EPEC) O55:H7 (sorbitol fermenting [SOR(+)] and β-glucuronidase positive [GUD(+)]), through sequential gain of virulence, phenotypic traits, and serotype change. Here we report six draft genomes of strains belonging to this evolutionary model: t ...[more]

PMID: 21317333

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Evolution of genomic content in the stepwise emergence of Escherichia coli O157:H7.

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Different IS629 transposition frequencies exhibited by Escherichia coli O157:H7 strains in the stepwise evolutionary model.

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