title: Genotyping of enteroaggregative Escherichia coli and identification of target genes for the detection of both typical and atypical strains.
abstract: Enteroaggregative Escherichia coli (EAggEC) is an important cause of diarrhea worldwide, and there is a need for better detection methods in diagnostic laboratories. The aims of this study were i) to characterize strains of EAggEC by assigning each isolate a genotypic profile and (ii) to determine target genes for the detection of both typical and atypical EAggEC. The heterogeneity of the EAggEC group makes selection of a single target gene difficult. The plasmid-encoded genes, aat, aggR, and aap, are all appropriate targets for the detection of typical EAggEC. Of the chromosomally encoded genes, aaiA would be the most suitable target gene to identify typical and atypical EAggEC. The astA gene, encoding the enteroaggregative heat stable toxin, although not specific for EAggEC, may be used effectively in combination with other specific EAggEC genes. A polymerase chain reaction test based on the detection of characteristic EAggEC virulence genes, such as aat, astA, and aaiA, would improve EAggEC diagnosis.
authors.affiliation: Laboratory of Enteric Pathogens, Centre for Infections, Health Protection Agency, NW9 5HT London, UK. claire.jenkins@royalfree.nhs.uk
authors.forename: Claire
authors.initials: C
authors.lastname: Jenkins
authors.forename: Henrik
authors.initials: H
authors.lastname: Chart
authors.forename: Geraldine A
authors.initials: GA
authors.lastname: Willshaw
authors.forename: Tom
authors.initials: T
authors.lastname: Cheasty
authors.forename: Henry R
authors.initials: HR
authors.lastname: Smith
mesh_terms: D015373:Bacterial Typing Techniques; D017931:DNA Primers; D015342:DNA Probes; D004269:DNA, Bacterial / Q000032:analysis; D004926:Escherichia coli / Q000145:classification / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000235:genetics*; D005456:Fluorescent Dyes; D005784:Gene Amplification; D005798:Genes, Bacterial / Q000235:genetics*; D005838:Genotype; D006801:Humans; D016133:Polymerase Chain Reaction; D012703:Serotyping
chemical_list: D017931:DNA Primers; D015342:DNA Probes; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D005456:Fluorescent Dyes