Abstract:

The aim of this study was to develop a method for the detection of enterohemorrhagic Escherichia coli O157:H7
(EHEC O157:H7) using dual-priming oligonucleotide (DPO) PCR technique. Based on DPO primer principle, a pair of
DPO primers was designed using the rfbE gene of EHEC O157:H7 as the target. Following the optimization of the reaction
system, the DPO-PCR method for the detection of EHEC O157:H7 was successfully developed with a sensitivity of
94 CFU/mL. Compared to the conventional PCR method, the DPO-PCR method was not sensitive to annealing temperature.
Thus, it was not required to repeatedly optimize primer and its annealing temperature during primer design and testing.
Moreover, the specific structure of DPO primers improved the specificity of conventional PCR method. Therefore, the
DPO-PCR method provides a new way for rapid and accurate detection of pathogenic microorganisms.

Key words: Escherichia coli O157:H7 (EHEC O157:H7), rfbE gene, dual-priming oligonucleotide polymerase chain reaction (DPO-PCR) method