title: Characteristics and prevalence within serogroup O4 of a J96-like clonal group of uropathogenic Escherichia coli O4:H5 containing the class I and class III alleles of papG.
abstract: The recent discovery of a geographically dispersed clonal group of Escherichia coli O4:H5 that includes prototypic uropathogenic strain J96 prompted us to determine the prevalence of J96-like strains within serogroup O4 and to further assess the characteristics of such strains. We used O:K:H;F serotyping, PCR-based genomic fingerprinting, pulsed-field gel electrophoresis (PFGE), multilocus enzyme electrophoresis (MLEE), and PCR detection of the three papG alleles and of the cytotoxic necrotizing factor 1 (cnf1) and aerobactin (aer) gene sequences to characterize the 15 O4 strains among 336 E. coli isolates from three clinical collections (187 from mixed-source bacteremia, 75 from urosepsis, and 74 from acute cystitis). J96-like strains constituted approximately half of the O4 strains, or 2% of the total population. In contrast to other O4 strains, the J96-like strains characteristically exhibited specific group III capsular antigens, the H5 flagellar and F13 fimbrial antigens, a distinctive PCR genomic fingerprint, the class III papG allele (plus, in 50% of strains, the enigmatic class I papG allele), and cnf1 but lacked aer. A subset of these strains was remarkably homogeneous with respect to all these characteristics and exhibited a distinctive PFGE fingerprint and MLEE pattern. These findings clarify the epidemiological relevance of J96 as a model extraintestinal pathogen, provide further evidence of the class I papG allele outside of strain J96, and offer insights into the evolution of E. coli serogroup O4.
authors.affiliation: VA Medical Center, and Department of Medicine, University of Minnesota, Minneapolis 55417, USA. johns007@maroon.tc.umn.edu
authors.forename: J R
authors.initials: JR
authors.lastname: Johnson
authors.forename: A E
authors.initials: AE
authors.lastname: Stapleton
authors.forename: T A
authors.initials: TA
authors.lastname: Russo
authors.forename: F
authors.initials: F
authors.lastname: Scheutz
authors.forename: J J
authors.initials: JJ
authors.lastname: Brown
authors.forename: J N
authors.initials: JN
authors.lastname: Maslow
mesh_terms: D018830:Adhesins, Escherichia coli / Q000235:genetics*; D000483:Alleles; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification / Q000235:genetics*; D036781:Fimbriae Proteins; D006801:Humans; D012703:Serotyping; D014552:Urinary Tract Infections / Q000382:microbiology*
chemical_list: D018830:Adhesins, Escherichia coli; C092426:PapG protein, E coli; D036781:Fimbriae Proteins