[Primarily study on a multiplex PCR-based system for the rapid detection of Salmonella spp., Shigella spp. and Escherichia coli O157:H7].
OBJECTIVE
To establish a multiplex PCR-based system for the simultaneous detection of Salmonella spp., Shigella spp. and Escherichia coli 0157:H7 in 12 hours.


METHODS
After 6 h nonselective enrichment in BPW, DNA template were prepared at 100 degrees C for 10 min. Three sets of primers were designed to amplify the gene segments of invA of Salmonella spp, ipaH of Shigella spp, and uidA of E. coli 0157:H7, and the products were analyzed by electrophoresis. At the same time, this system was optimized, and the specificity and sensitivity of this system were evaluated.


RESULTS
Three target bacteria were detected in 12 h by using this multiplex PCR-based system. The sensitivity of it was up to 10-30 cfu/ml, and the high specificity was demonstrated by detecting 23 target stains and 15 non-target stains.


CONCLUSION
A rapid, specific, and sensitive multiplex PCR-based system for the simultaneous detection of Salmonella spp., Shigella spp. and E. coli 0157:H7 in 12 h has been studied primarily.