Investigation of the presence of Stn virulence gene in human Salmonella serovars

Background and Aim : Salmonellosis is a common zoonotic disease caused by Salmonella. Because diagnosis methods based on culture and isolation are time-consuming, using methods that can quickly detect the presence of Salmonella in suspected specimens can be effective in preventing disease and outbreaks. Stn is a virulence factor in Salmonella and is known to cause diarrhea because it has been shown to have enterotoxic activity. The present study aimed to investigate the presence of Stn gene in human Salmonella serovars as a molecular diagnostic method.Methods : ۴۳ Salmonella serovars isolated from humans were prepared and samples were cultured on differential media. Serovars were identified using specific antiserum based on the Kauffman-White table. After extraction of genomic DNA, PCR reaction was performed using specific primers for Stn gene and the PCR product was evaluated for the presence of Stn by electrophoresis on agarose gel.Results : In this study, most human serovars included Salmonella paratyphi A, Salmonella paratyphi B and Salmonella enteritidis. All ۴۳ Salmonella samples was positive for the Stn virulence gene.Conclusion : Since the Stn gene plays an important role in the pathogenesis of Salmonella and due to the fact that it is specific to Salmonella, it can be used in the manufacture of diagnostic kits such as ELISA as well as the production of recombinant vaccines.

Keywords:

Salmonellosis , Salmonella serovars , Molecular identification , Stn gene