Quantitative analysis of various virulance genes (PVL,LukED,γ-hemoliz) by real-time PCR of Staphylococcus aureus strains isolated from bovine mastitis

In 98 staphylococcus aureus (s. aureus) strains isolated from bovine mastitis,presence/absence of virulence genes such as panton-valentine leukocidin (pvl),γ-hemolysis and luked and quantitative analysis were conducted by real-time pcr. according to real-time pcr pvl,γ-hemolysis and luked genes of 98 s. aureus strains were found as 70.40%,90.81% and 66.32%,respectively. as a result of the quantitative analysis of virulence genes according to strains,they are grouped into 3 groups as 40<-10,000,10,000-100,000 and 100,000< iu/ml considering viral gene amount. the amount of pvl gene among these groups was determined as 27.55%,9.18% and 32.65% respectively,and γ-hemolysis as 48.97%,39.79% and 2.04% and luked as 45.91%,14.28% and 6.12%. as a result,in s. aureus strains isolated from bovine mastitis the prevalence of these virulence genes were higher. therefore it is deduced that pvl,γ-hemolysis and luked may be important virulence factors in the pathogenesis of s. aureus. copyright 2016 zoological society of pakistan.