title: Cytolethal distending toxin gene cluster in enterohemorrhagic Escherichia coli O157:H- and O157:H7: characterization and evolutionary considerations.
abstract: We identified a cytolethal distending toxin (cdt) gene cluster in 87, 6, and 0% of sorbitol-fermenting (SF) enterohemorrhagic Escherichia coli (EHEC) O157:H(-), EHEC O157:H7, and E. coli O55:H7/H(-) strains, respectively. The toxin was expressed by the wild-type EHEC O157 strains and by a cdt-containing cosmid from a library of SF EHEC O157:H(-) strain 493/89. The cdt flanks in strain 493/89 were homologous to bacteriophages P2 and lambda. Our data demonstrate that cdt, encoding a potential virulence factor, is present in the EHEC O157 complex and suggest that cdt may have been acquired by phage transduction.
authors.affiliation: Institut für Hygiene, Universitätsklinikum Münster, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Janka
authors.forename: Martina
authors.initials: M
authors.lastname: Bielaszewska
authors.forename: Ulrich
authors.initials: U
authors.lastname: Dobrindt
authors.forename: Lilo
authors.initials: L
authors.lastname: Greune
authors.forename: M Alexander
authors.initials: MA
authors.lastname: Schmidt
authors.forename: Helge
authors.initials: H
authors.lastname: Karch
mesh_terms: D001427:Bacterial Toxins / Q000235:genetics*; D001483:Base Sequence; D005075:Biological Evolution; D003090:Coliphages / Q000235:genetics; D019453:Escherichia coli O157 / Q000235:genetics* / Q000472:pathogenicity; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D014161:Transduction, Genetic
chemical_list: D001427:Bacterial Toxins; C067044:cytolethal distending toxin