title: Improvement of biomolecular methods for the identification and typing of Escherichia coli O157:H7 isolated from raw meat.
abstract: The aim of the study was to evaluate the sensitivity of two m-PCR methods for the quantitative determination of E. coli O157:H7 in foodstuffs. Genomic serotyping was carried out on bacterial cultures, and the necessary time was optimized to increase the resolution of the method. Subsequently, artificial contamination trials using meat were conducted to assess method accuracy in foodstuffs and pursue the genetic typing of pathogens. Measurement thresholds were shown to range between 10(5) and 10(6) CFU/mL, but were reduced by four logarithmic cycles in 80% of samples. Relative to the meat contamination trials, serotypes were identified after 24 hours, corresponding to 10 CFU/mL inoculum, with higher rates seen when m-TSB was used for enrichment. Inoculated samples were found to contain three virulence factors (hlyA, eaeA, and stx1).
authors.affiliation: Department of Animal Health, University of Parma, Parma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Paris
authors.forename: S
authors.initials: S
authors.lastname: Bonardi
authors.forename: C
authors.initials: C
authors.lastname: Bacci
authors.forename: E
authors.initials: E
authors.lastname: Boni
authors.forename: F
authors.initials: F
authors.lastname: Salmi
authors.forename: L
authors.initials: L
authors.lastname: Bassi
authors.forename: F
authors.initials: F
authors.lastname: Brindani
mesh_terms: D000818:Animals; D002417:Cattle; D019453:Escherichia coli O157 / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D005516:Food Microbiology; D015964:Gene Expression Regulation, Bacterial; D023281:Genomics; D008460:Meat / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity; D012703:Serotyping / Q000379:methods; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D037521:Virulence Factors
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