Molecular Study of Virulence Genes of Staphylococcus aureus Isolates from Various Clinical Origins by PCR

Abstract

Staphylococci pathogen was blamable for a huge scale of infections in human because of their invention of secreted and other cell-surface related virulence factors that regulate by various genes. This study was carrying out to realize the frequency of Staphylococcus species in Hillah city using specific genes for that purpose.PCR technique was applied to amplify the staphylococcal virulence genes like sea, see, eta, tst, coa, nuc, seb, femA, mecA, etb, cna, fib and fnbA, and they determined either multiplex or uniplex PCRs depending on the sizes of the PCR products amplicons.Out of 229 collected samples from different clinical sources, only 100Staphylococcus aureus (43.7%) were revealed. According to phenotypic and biochemical tests, the isolates can be distributed as follow; Urine 22 (9.6%), Pus 19 (8.3 %), Sputum 12 (5.2%), CSF 4 (1.7%), Blood 32 (14%), Pericardial fluid 9 (3.9%) and Peritoneal fluid 2 (0.9%). From the 13 examined genes, most abundant gene was fib (27 cases) followed by femA (25 cases). While tst gene reported as the least frequently detected gene. S. aureus isolated from Blood infection formed the highest ratio among genes reveals in this study (194; 38.6%) followed by pus infections isolates (120; 23.9%), urine infections isolates (102; 20.3%), sputum isolates (32; 6.4%), Pericardial fluid (28; 5.6%), CSF (19; 3.8%) and finally Peritoneal fluid (8; 1.6%).