Loop-mediated isothermal amplification for detecting enterohemorrhagic Escherichia coli O157:H7: a comparison with PCR / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To establish a rapid method of loop-mediated isothermal amplification (LAMP) for detecting enterohemorrhagic Escherichia coli (EHEC) O157H7.</p><p><b>METHODS</b>Six primers that specifically recognized the rfbE gene of EHEC O157H7 were designed. Under the optimized reaction conditions, LAMP and PCR were evaluated for the sensitivity and specificity in the detection of 39 laboratory samples of EHEC O157H7 strains, and their detection results of contaminated fresh pork samples were compared.</p><p><b>RESULTS</b>LAMP assay correctly identified all the 7 EHEC O157H7 strains and showed negative results for all the 32 non-EHEC O157H7 strains. The detection limit of LAMP was much lower than that of rfbE-PCR (10 vs 100 cfu/ml). In the detection of the contaminated pork samples, both LAMP and PCR yielded results consistent with those by the conventional detection method.</p><p><b>CONCLUSION</b>The rfbE-based LAMP assay can serve as a rapid, sensitive, specific and low-cost means for detecting EHEC O157H7 strain.</p>