DNA-PROBE FOR DETECTING SALMONELLA-ENTERITIDIS IN FOOD

Salmonellosis is the most frequently reported foodborne illness in the United States, with Salmonella enteritidis being the leading cause of these outbreaks. Nucleotide sequence comparisons of the Salmonella pl asmid virulence (spv) genes of S. enteritidis with those of S. typhimu rium and S. dublin have revealed that a single base-pair change unique to S. enteritidis is present in the spvA gene. An 18-base synthetic o ligonucleotide probe (SE-probe) that is completely homologous to the s pvA gene of S. enteritidis but which has one base pair mismatch with o ther salmonellae was shown to be specific for S. enteritidis. in colon y hybridization blots, 129 isolates of S. enteritidis, 29 other specie s of Salmonella, and 17 non-Salmonella spp, were tested with the SE-pr obe. The SE-probe hybridized with 96% of the S, enteritidis strains te sted but did not react with the other Salmonella or non-Salmonella str ains. These data suggest that the SE-probe can be used in a specific a nd rapid detection assay for S. enteritidis.