Differentiation of stx1A gene for detection of Escherichia coli serotype O157: H7 and Shigella dysenteriae type 1 in food samples using high resolution melting curve analysis

摘要

serotype O157: H7 and type 1 as the Shiga toxin‐producing bacteria cause some acute gastrointestinal and extraintestinal diseases such as hemorrhagic uremic syndrome and bloody diarrhea in human. genes are the key virulence factors in these pathogens. The aim of this study was to develop HRMA assay to differentiate gene for detection of serotype O157: H7 and type 1 and determine the prevalence of these pathogens in food samples using this method. PCR‐HRMA assay and gold standard methods have been carried out for identification of pathogens among 135 different food samples. We found HRMA method a sensitive and specific assay (100 and 100%, respectively) for differentiation of gene, consequently, detection of these pathogens in food samples. Also, the highest prevalence of serotype O157: H7 and type 1 harboring gene was observed in raw milk and vegetable salad samples, respectively. HRMA as a rapid, inexpensive, sensitive and specific method is suggested to be used for differentiation of gene to detect serotype O157: H7 and type 1 as the key pathogens for safety evaluation of food samples.