METHICILLIN-RESISTANT Staphylococcus aureus

Abstract

Staphylococcus aureus is a major human pathogen with several virulence factors and capacity to acquire resistance to various antibiotics. This ability is enhanced by constant emergence of new clones making S.aureusa "superbug". The cause of resistance to methicillin (a beta lactum antibody) is the mecA gene which is present genetic element "the staphylococcal cassette chromosome mec” (SSC mec). Seven major variants of SSCmec type 1 to 7 are known. The techniques such as Pulsed-field gel electrophoresis (PFGE), Multilocus sequence typing (MLST), S.aureus protein A (spa) typing and SSC mec typing for only MRSA are used to study evolution of MRSA clones that have emerged since the early 1960s. This review article describes the latest observations on molecular characterisation and evolution of S.aureus along with some challenges that researchersface.