Evaluation of real time PCR for detection of clinical isolates of Staphylococcus aureus and methicillin-resistance strains based on melting curve analysis method

Rapid and timely detection of Staphylococcus aureus can play a significant role in the treatment of staphylococcal infections.Impresingly, by precise designing methods which have acceptable sensitivity and specificity, can identify species and even antibiotic-resistant strains. The purpose of this study was to evaluate the real time PCR diagnostic method based on the melting curve analysis for the detection of clinical isolates of S. aureus and the methicilin resistance gene.
In this experimental study, clinical isolated of S. aureus was used from the Microbiology Bank of Hamadan University of Medical Sciences. The primer design was done by selecting (ITS) target for S. aureus and the mecA gene for methicillin-resistant strains. Real-time PCR and DNA melting curves analysis were used to determine the analytical specificity and sensitivity of the designed primers.
The analytical specificity of the primers was 83.79 ° C for S. aureus and 76.6 ° C for methicillin resistant Staphylococcus aureus respectively. The analytical sensitivity of the primers was 15 CFU/ml bacteria for ITS gene and 25 CFU/ml bacteria for mecA gene.
By selecting appropriate primers and using sensitive molecular techniques, which could be the main factors for designing of both quick and accurate method, it is possible to identify invasive bacteria such as S. aureus.