Abstract: A real-time PCR method was developed for the rapid and specific detection of Escherichia coli O157:H7. A pair of primers was designed according to the conserved sequence of rfbE gene in Escherichia coli O157:H7. The SYBR Green I real-time PCR method for detecting Escherichia coli O157:H7 was established. The sensitivity and specificity of this method was analyzed through the comparison with traditional PCR methods. The results indicated that the developed SYBR Green I real-time PCR method had the characteristics of excellent specificity, sensitivity and repeatability. The sensitivity of this developed method was 2 × 101 CFU/mL in pure cultures and 1 × 102 CFU/mL in artificially contaminated meat samples. In addition, the established method was also used for the detection of clinical samples. The results showed that the detection rate of real-time PCR for Escherichia coli O157:H7 was significantly increased when compared with traditional PCR. Therefore, the established real-time PCR method is a rapid, specific and sensitive method for the detection of Escherichia coli O157:H7.

Key words: Escherichia coli O157:H7, rfbE gene, SYBR Green I, real-time PCR