Changes in ahpF and tviA genes expression in Salmonella enterica PTCC 1230upon osmotic and oxidative stress using Real-Time PCR

Salmonella is a member of the Enterobacteriaceaefamily causing infectious disease in human and animals. The diseases caused by this bacterium are typhoid, bacteremia, enterocolitis, salmonellosis which are a health problem worldwide. The aim of this study was to evaluate the changes in expression of ahpF and tviAgenes in Salmonella enterica PTCC 1230 exposed to osmotic and oxidative stresses. For osmotic stress, S.enterica PTCC 1230 was subjected to 6, 8, 10, 12, and 14% (W/V) NaCl concentrations and for the oxidative stress, H2O2at concentrations of 1200, 2400, 4800, 6000 and 7200 ppm were used. Change in expression of ahpF and tviA genes were quantified using Real-time PCR method. Based on the obtained results, NaCl at concentrations of 14% and 10% and H2O2atconcentrations of 7200 (ppm) and 6000 (ppm) had maximum effects on the bacterial growth, respectively. In concentration of 7200 ppm, the expression of ahpFgene increased about 1.8 and 2.5-fold more thanH2O2at 6000 ppm concentration and reference gene (16S rRNA).Also, in 14% (W/V) sodium chloride concentration the expression of tviAgene increased about1.3 and 1.5 fold more than 10% and the reference gene (16S rRNA), respectively. Discussion and Conclusion: In this study, changes in expression level of ahpF and tviAgenes upon oxidation and osmotic stresses were studied in Salmonella entericaPTCC 1230. The overall results of this study showed that the expression level of both ahpF and tviAgenes were increased in stress condition and we recommend the study of the other genes incorporate in responses to environmental stresses.