EPIDEMIOLOGY, ECOLOGY, AND MOLECULAR GENETICS OF ANTIMICROBIAL RESISTANCE IN PATHOGENIC AND COMMENSAL BACTERIA FROM FOOD ANIMALS
Location: Bacterial Epidemiology and Antimicrobial Resistance
Title: Salmonella enterica Genomics and Antimicrobial Resistance
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 2, 2009
Publication Date: April 2, 2009
Citation: Frye, J.G., Cray, P.J., Jackson, C.R., Englen, M.D., Berrang, M.E., Meinersmann, R.J. 2009. Salmonella enterica Genomics and Antimicrobial Resistance. University of Georogia, Microbiology Departmental Seminar. April 2,2009. Athens, GA.
Salmonella is a prevalent food-borne pathogen and a model system for the study of virulence and pathogenesis. The development of DNA microarray technology has furthered investigation of complicated regulatory pathways used during survival and pathogenesis as well as genome organization that leads to the variations in Salmonella serotypes. There are over 2400 Salmonella serotypes each of which differs in their ability to cause disease in humans and animals, persist within the host, and survive in the environment. 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 important pathogenic and commensal bacteria such as: Campylobacter, E. coli, Enterococcus, Listeria, MRSA, Salmonella and A. baumannii.