Abstrakt

Molecular analysis of Coagulase (coa) gene polymorphism in clinical isolates of Staphylococcus aureus by PCR-RFLP

N.G.Ramesh Babu, GB.Bakhya Shree, L.Rekha, P.Karthiga

Coagulase enzyme is one of the virulence factors of Staphylococcus aureus . This study is based on the molecular analysis of the coagulase encoding gene. The polymorphism of the coa gene existing in different Staphylococcus aureus have been analyzed in this study. Staphylococcus aureus (14 isolates) were used for this study, among which 12 were isolated from clinical samples such as infected blood, urine, pus, wounds and 2 isolates were maintained as standards obtained from ATCC. The 12 isolates were identified as coagulase positive and 2 isolates were coagulase negative by various biochemical tests. For further confirmation, DNA from each sample was isolated and the coa gene was amplified with appropriate primers. The PCR results of 12 coagulase positive S.aureus gave two different sets of amplicons. The PCR products were subjected to restriction digestion using RFLP with AluI. Different restriction patterns (5) were obtained in RFLP. This variation in restriction patterns is because of the VNTRs present in each isolates. This study emphasizes the genotypic variation among different S.aureus isolates of samples, which may be considered as an important criterion while treating Staphylococcal infections.