INTERVENTIONS AND METHODOLOGIES TO REDUCE HUMAN FOOD-BORNE BACTERIAL PATHOGENS IN CHICKENS
Location: Poultry Microbiological Safety Research
Title: Predicting Salmonella enterica subsp. enterica Serotypes by Repetitive Extragenic Palindromic Sequence-Based PCR
Submitted to: American Society for Microbiology
Publication Type: Abstract Only
Publication Acceptance Date: April 28, 2008
Publication Date: June 3, 2008
Citation: Seal, B.S., Wise, M.G., Siragusa, G.R., Plumblee, J., Cray, P.J., Atkins, E.H., Ross, T.A., Healy, M. 2008. Predicting Salmonella enterica subsp. enterica Serotypes by Repetitive Extragenic Palindromic Sequence-Based PCR. American Society for Microbiology. Y-017.
The DiversiLabTM System, which employs repetitive extragenic palindromic sequence-based PCR (rep-PCR) to genotype microorganisms, was evaluated as a method to predict the serotype of Salmonella isolates. Two hundred and thirty-three Salmonella isolates belonging to 14 frequently isolated serotypes from poultry were used to create a DNA fingerprint library with the DiversiLab software. Subsequently, a blinded set of 42 poultry-related Salmonella isolates were typed with the DiversiLab System, and queried against the library in an attempt to putatively assign a serotype designation. The query isolates were previously serotyped employing standard techniques. Using clustering of the resultant microchip patterns by the DiversiLab dendrogram system and similarity percentages as a guide, 28 isolates had concordant serotypes. A further set of six were correctly classified as one of two very closely related serotypes (Hadar or Istanbul). Six other isolates showed no match to the database (similarly values < 95%) and these proved to be serotypes not included in the library. The serological identification of two isolates was not concordant with the rep-PCR predicted serotype at the 95% similarity threshold. Both discrepant samples, identified by traditional methods as Bredeney and Lille, are relatively rare and graph overlays with the top library match showed distinct amplification product differences. Since traditional serotyping methodology can take several days to provide serotype information, the DiversiLab System holds promise as a more rapid and highly reliable serotype identification system for members of this group.