title: Detection of five Shiga toxin-producing Escherichia coli genes with multiplex PCR.
abstract: Escherichia coli serogroup O157 is the pathogen most commonly associated with foodborne disease outbreaks, but epidemiological studies suggest that non-O157 Shiga toxin-producing E. coli (STEC) is a major player as well. The ten most clinically relevant STECs belong to serogroups O26, O103, O111, O145, O157, O91, O113, O128, O45, and O121; but emerging strains, such as O104:H4 that was identified with the 2011 German outbreak, could become more prevalent in the future. A 75-min conventional multiplex PCR assay, IS-5P, targeting the four virulence factors stx1, stx2, eae, and ehxA plus the O157:H7-specific +93 uidA single nucleotide polymorphism was developed to better assess the potential pathogenicity of STEC isolates. All 212 STEC DNAs showed one to five amplification products, while the non-E. coli DNA did not react to this multiplex PCR assay. Enrichment broths obtained from baby spinach, alfalfa sprouts, and cilantro artificially inoculated with O26, O103, and O121 STECs reacted positively to the multiplex assay. Unlike the current FDA BAM 5P PCR, designed for the specific detection of O157:H7, IS-5P will identify potentially harmful O157:H7 and non-O157 STECs so they can be removed from the nation's food supply.
authors.affiliation: U.S. Food & Drug Administration, Center for Food Safety and Applied Nutrition, Office of Regulatory Science, College Park, MD 20740, USA. Electronic address: insook.son@fda.hhs.gov.
authors.forename: Insook
authors.initials: I
authors.lastname: Son
authors.affiliation: U.S. Food & Drug Administration, Center for Food Safety and Applied Nutrition, Office of Regulatory Science, College Park, MD 20740, USA. Electronic address: rachel.binet@fda.hhs.gov.
authors.forename: Rachel
authors.initials: R
authors.lastname: Binet
authors.affiliation: Oak Ridge Research Institute for Science and Education, PO Box 117, Oak Ridge, TN 37830, USA. Electronic address: anna.laasri@fda.hhs.gov.
authors.forename: Anna
authors.initials: A
authors.lastname: Maounounen-Laasri
authors.affiliation: U.S. Food and Drug Administration San Francisco District Laboratory, Alameda, CA 94502, USA. Electronic address: andrew.lin@fda.hhs.gov.
authors.forename: Andrew
authors.initials: A
authors.lastname: Lin
authors.affiliation: U.S. Food & Drug Administration, Center for Food Safety and Applied Nutrition, Office of Regulatory Science, College Park, MD 20740, USA. Electronic address: thomas.hammack@fda.hhs.gov.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Hammack
authors.affiliation: U.S. Food & Drug Administration, Center for Food Safety and Applied Nutrition, Office of Regulatory Science, College Park, MD 20740, USA. Electronic address: julie.kase@fda.hhs.gov.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Kase
mesh_terms: D001427:Bacterial Toxins / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics; D005506:Food Contamination / Q000032:analysis*; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods*; D054323:Shiga-Toxigenic Escherichia coli / Q000235:genetics* / Q000302:isolation & purification*; D014675:Vegetables / Q000382:microbiology*
chemical_list: D001427:Bacterial Toxins; D029968:Escherichia coli Proteins
keywords: Escherichia coli; Multiplex PCR; STEC; Virulence