Evaluation of ehxA, stx۱, and stx۲ Virulence Gene Prevalence in Cattle Escherichia coli Isolates by Multiplex PCR

Today, it is nearly ۲۵ years past from investigation of Shiga toxigenic Escherichia coli (STEC) which is able to produce Shiga toxins and cause different gastroenteritis. Since incidence of gastroenteritis due to STEC is increasing, it's necessary to develop rapid, specific and accurate procedures like PCR. In this study, we used PCR method to detect and identify STEC in cultures of ۵۵ Escherichia coli positive feces from cattle. The assay utilized three specific primer pairs to detect ehxA, stx۱, and stx۲ (including variants of Stx۲) genes producing ۳۲۱, ۳۴۸, and ۵۸۴ base pairs, respectively. Finally, about ۲۱.۸% of Escherichia coli isolates were positive for ehxA, stx۱, and/or stx۲ genes. According to other research, the prevalence of stx۲ genes was higher than stx۱ genes but not about ehxA genes.

Keywords:

Escherichia coli , EHEC , stx , ehxA , Multiplex PCR