Molecular identification of virulence gene hlyE in differentserovars of Salmonella isolated from human and livestock in Iran

Background and Aim : Salmonella is zoonotic bacteria and one of the most frequently isolatedfoodborne pathogens. Recently, there is no cost effective vaccine available, so it is a majorworldwide public health concern. The hlyE gene can be activated by the salmonella transcriptionfactor (slyA). This gene encodes HlyE protein which is a pore-forming hemolysin that accumulatesin the periplasm. The aim of this study was to analysis of the presence of hlyE virulence gene indifferent serovars of Salmonella isolated from human and livestock in Iran, so that it can be usedfor diagnosis.Methods : A total ۶۸ isolate of ۲۵ different Salmonella serovars from the microbial collection ofthe Razi Vaccine and Serum Research Institute were used. Biochemical tests and serotyping wereused to confirm the serovars. DNA extraction was performed by boiling method. Detection hlyEgene (۲۹۴bp) in different Salmonella serovars was performed by PCR then amplified productswere analyzed by agarose gel electrophoresis.Results : A total ۵۰ out of ۶۸ Salmonella isolates were positive (۷۳.۵%) for hlyE gene. The resultsshowed the presence of hlyE gene was the most common in S.typhi (۱۰۰%),fallowed byS.paratyphiB (۸۵.۷%) and S.paratyphiA (۸۴.۶%), while low prevalence of this gene was observedin S.typhimurium (۴۲.۸%).Conclusion : The results indicated the presence of the hlyE gene in different Salmonella serovars.The detection of this gene helps to understand the pathogenesis of salmonella. Moreover, presenceof hlyE gene in S.typhi shows that they are specific target for molecular identification.