ARS | Publication request: Molecular Characterization of Salmonella enterica and detection of antimicrobial resistance genes

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: September 14, 2009
Publication Date: September 14, 2009
Citation: Frye, J.G., Cray, P.J., Jackson, C.R., Englen, M.D., Berrang, M.E., Meinersmann, R.J. 2009. Molecular Characterization of Salmonella enterica and detection of antimicrobial resistance genes [abstract]. National Poultry Improvement Plan Salmonella Workshop. 6:1-21.

Technical Abstract: Salmonella is a prevalent food-borne pathogen that is often associated with poultry. Identification of Salmonella serotype is a key step in classification of this bacterium. However, serotyping is a slow and difficult process. Therefore a molecular method was developed for the rapid and simple determination of Salmonella serotypes. Comparative genomic hybridization (CGH) was used to reveal that each serotype contains a core of about 4000 genes in addition to 400-600 genes that are serotype specific. Some of these genes are shared between closely related serotypes, however, others are shared with very distantly related serotypes or other organisms via horizontal gene exchange. Genomic targets from this work were identified based on their differential distribution among common serovars. A multiplex PCR incorporating a fluorescently labeled primer and analyzed in an automated sequencer was used to detect these unique genes and is capable of correctly identifying the top 50 Salmonella serotypes in a rapid high-throughput assay. Antimicrobial resistance in Salmonella is also a major concern. Analysis of mutlidrug resistant (MDR) Salmonella is hampered by difficulty determining which resistance genes are responsible for pheontypes observed in isolates. To address this, a microarray for the detection of antibiotic resistance genes was developed. This microarray is able to detect hundreds of resistance genes, and can be used to analyze a variety of diverse bacteria including Salmonella.