EMA-PCR Detection of Enterohemorrhagic Eschrichia ColiO157∶H7

Objective?A rapid and effective method with ethidium monoazide bromide (EMA) in combination with PCR (EMA-PCR) was established to detect live Enterohemorrhagic Eschrichia Coli O157∶H7. Methods?The rfbE gene was used as the target gene for PCR detection of Eschrichia Coli O157∶H7 by utilizing its pure isolates after the treatment of EMA as the template. The EMA concentration and reaction time was optimized. Results?The use of 10 μg/mL or less EMA did not inhibit the PCR amplification of DNA derived from viable bacteria. The PCR amplification of DNA derived from 2×10⁷ CFU/mL dead cells can be inhibited by 0.5 μg/mL EMA. The sensitivity of the method was 2×10⁴CFU/mL. The results demonstrated that it could detect 1% live bacteria from a mixed bacterial population. Conclusion?EMA-PCR can effectively detect live bacteria of O157∶H7, it could be a potential rapid detection method applied in public health emergent events.