An Escherichia coli reference collection group B2-and uropathogen-associated polymorphism in the rpoS-mutS region of the E-coli chromosome

Chromosomal DNAs of enterohemorrhagic, uropathogenic, and laboratory attenuated Escherichia coli strains differ in the rpoS-mutS region. Many uropathogens lack a deletion and an insertion characteristic of enterohemorrhagic strains. At the same chromosomal position, they harbor a 2.1-kb insertion of unknown origin with a base composition suggestive of horizontal gene transfer. Unlike virulence determinants associated with urinary tract infection and/or neonatal meningitis (pap or prs, sfa, kps, and hly), the 2.1-kb insertion is shared by all group B2 strains of the E. coli Reference Collection.