Detection of virulence determinants by real time PCR in E. coli isolated from mutton

Ninety three Escherichia coli isolates belonging to 35 serotypes isolated from market mutton were tested to find out the prevalence of virulence determinants, Verotoxin 1 (VT1), Verotoxin 2 (VT2), Intimin (eae) genes and enterohemolysin production. Real Time PCR based detection was carried out for virulence genes using SYBR green format and amplicons were confirmed by melt curve analysis. Prevalence of VT1 gene in these isolates was much higher (38.70%) on the other hand, that of VT2 gene was nil (0%) while that of eae was very low (3.22%). Enterohemolysin production was found in 31.18% isolates when tested on washed sheep blood agar supplemented with CaCl2. All enterohemolysin producing isolates were also positive for the VT1 gene.