Detection and antibiotic resistance genes of diarrheagenic Escherichia coli from Pathotypes in Children Under five years

Escherichia coli exists both as a benign resident in the intestines of many mammals and as a potential harmful pathogen.this study aimed to investigate about many virulence genes can be acquired by commensal E. coli to become pathogenic one and specifically causes diarrhea.100 stool samples were taken from healthy children as a control group, and 500 stool samples were taken from children under five who had diarrhea.E. coli was isolated using standard techniques from every sample, then E. coli isolates from both patients and controlled has molecularly genotyped to characterize commensal ones, the investigation about Stx1, Stx2 using multiplex PCR.The results showed that 150(30%) of the isolated bacteria from diarrhea samples were E.coli ,122 of them were commensal ones.The results also showed that Stx1 gene present in all commensal isolated E.coli from patients ,while Stx2 was present in 118samples only.These genes can be easily transferred to commensal E. coli via horizontal gene transfer under many serious conditions such as malnutrition , abuse of antimicrobial agents and poor hygiene.Beside disease these transferred genes can also change both core genome and the pan-genome in commensal bacteria.