title: Sequence diversity of the Escherichia coli H7 fliC genes: implication for a DNA-based typing scheme for E. coli O157:H7.
abstract: Flagellar (H) antigens are mostly encoded by genes at the fliC locus in E. coli. We have sequenced 11 H7 fliC genes from Escherichia coli strains that belong to seven O serotypes. These sequences, together with those of nine other H7 fliC genes (from strains of three different O serotypes) sequenced recently (S. D. Reid, R. K. Selander, and T. S. Whittam, J. Bacteriol. 181:153-160, 1999), include 10 different sequences. The differences between these 10 sequences range from 0.06 to 3.12%. By comparison with other E. coli flagellin genes, we have identified primer length sequences specific for H7 genes in general and others specific for H7 genes of O157 and O55 strains: the specificity was confirmed by PCR testing the type strains for all 53 E. coli H types. We have previously identified genes specific for the E. coli O157 antigen, and use of the combination of O157- and H7-specific primers allows the sensitive and rapid detection of O157:H7 E. coli strains, which cause the majority of hemorrhagic colitis cases.
authors.affiliation: Department of Microbiology, The University of Sydney, Camperdown, New South Wales 2006, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.forename: D
authors.initials: D
authors.lastname: Rothemund
authors.forename: H
authors.initials: H
authors.lastname: Curd
authors.forename: P R
authors.initials: PR
authors.lastname: Reeves
mesh_terms: D001483:Base Sequence; D016384:Consensus Sequence; D017931:DNA Primers; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D019453:Escherichia coli O157 / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D005408:Flagellin / Q000235:genetics*; D014644:Genetic Variation; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D012703:Serotyping
chemical_list: D017931:DNA Primers; D005408:Flagellin