Sensitive and Rapid Molecular Detection Assays for Salmonella enterica Serovars Typhimurium and Heidelberg
Authors: McCarthy, Noelle1; Reen, F. Jerry2; Buckley, James F.3; Frye, Jonathan G.4; Boyd, E. Fidelma5; Gilroy, Deirdre6
Source: Journal of Food Protection®, Volume 72, Number 11, November 2009 , pp. 2350-2357(8)
Abstract:
Salmonella enterica is a significant cause of gastroenteritis worldwide, with serovars Typhimurium and Heidelberg being particularly prevalent, which have broad host ranges infecting poultry, dairy animals, and humans. Traditional methods used for the detection of Salmonella from contaminated food products are time-consuming and labor-intensive. The aim of this study was to develop a sensitive and rapid PCR-based detection method with optimized specificity for high-throughput screening of food and clinical samples. We used bioinformatics to identify potential serovar-specific regions from the available S. enterica sequenced genomes. We designed primer pairs to targeted regions unique to Typhimurium and Heidelberg. A primer pair targeting a putative cytoplasmic protein STM4492 amplified a 759-bp product specific to Typhimurium, and a primer pair targeting a putative inner membrane protein STM2745 amplified a 199-bp product from both Typhimurium and Heidelberg. A primer pair for the oriC locus was used to identify all Salmonella. We screened 217 isolates including the Salmonella reference collections A and B, validating the specificity of each primer set. Next, a multiplex PCR (mPCR) assay and quantitative real-time PCR assay were optimized for identification and differentiation of Typhimurium and Heidelberg. An mPCR assay was developed and successfully detected S. enterica isolates from inoculated Cheddar cheese, raw turkey, and cooked turkey at concentrations as low as 1 CFU/g of food. The reaction conditions for this mPCR have significantly reduced the time needed to identify S. enterica Typhimurium and Heidelberg, making this a rapid selective tool.Document Type: Research article
Affiliations: 1: Department of Microbiology, University College, Cork, National University of Ireland, Cork, Ireland, Department of Biology, Cork Institute of Technology, Cork, Ireland 2: Department of Microbiology, University College, Cork, National University of Ireland, Cork, Ireland 3: Veterinary Food Safety Laboratory, Cork County Council, Cork, Ireland 4: Bacterial Epidemiology and Antimicrobial Resistance Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Athens, Georgia, USA 5: Department of Biological Sciences, University of Delaware, Newark, Delaware 19716, USA;, Email: fboyd@udel.edu 6: Department of Biology, Cork Institute of Technology, Cork, Ireland
Publication date: 2009-11-01
- IAFP members must first sign in on the right to access full text articles of JFP First published in 1937, the Journal of Food Protection®, is a refereed monthly publication. Each issue contains scientific research and authoritative review articles reporting on a variety of topics in food science pertaining to food safety and quality. The Journal is internationally recognized as the leading publication in the field of food microbiology with a readership exceeding 11,000 scientists from 70 countries. The Journal of Food Protection® is indexed in Index Medicus, Current Contents, BIOSIS, PubMed, Medline, and many others.
Print and online subscriptions are available to Members and Institutional subscribers. Online visitors who are not IAFP Members or journal subscribers will be charged on a pay-per-view basis. Information can be obtained by calling +1 800.369.6337; +1 515.276.3344; fax: +1 515.276.8655, E-mail: info@foodprotection.org or Web site: www.foodprotection.org - Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Information for Advertisers
- ingentaconnect is not responsible for the content or availability of external websites
- In this: publication
- By this: publisher
- In this Subject: Nutrition & Food
- By this author: McCarthy, Noelle ; Reen, F. Jerry ; Buckley, James F. ; Frye, Jonathan G. ; Boyd, E. Fidelma ; Gilroy, Deirdre

Shopping cart
Receive new issue alert
Get Permissions