Multiplex real-time PCR method to identify Shiga toxin genes stx1 and stx2 and Escherichia coli O157:H7/H- serotype

A multiplex real-time PCR method to simultaneously detect the stx1 and stx2 genes of Shiga toxin-producing Escherichia coli and a unique conserved single-nucleotide polymorphism in the E. coli O157:H7/H- uidA gene has been developed. There is more than 98.6% sensitivity and 100% specificity for all three gene targets based on a panel of 138 isolates. The PCR efficiencies were greater than or equal to1.89, and as few as 6 CFU/reaction could be detected.