Staphylococcus aureus is an important bacterial pathogen. Worldwide, the prevalence of MRSA infection varies from 5% to 69.1%. Increase in frequency of MRSA globally and hence the need for accurate detection, have led the use of molecular methods for rapid confirmation of S. aureus and MRSA. Species specific markers like auxiliary genes (fem) and thermonuclease (nuc) gene along with the methicillin resistance determinant, mecA, have been used in different combinations by several investigators worldwide for the identification of MRSA. The scope and main objective of this study is to determine prevalence of MRSA in clinical isolates in a tertiary care hospital, to determine the major mechanism of methicillin resistance and to design a simple molecular protocol to directly process and screen uncultured clinical samples for MRSA (data published earlier). This abstract focuses on the studies involving investigations to understand the reasons for poor reliability of fem genes as species markers and some experiments to investigate the drug sensitivity (data published earlier), physiology, and morphology of the cells in fem genes sequence variants which we identified during our initial screening of clinical isolates.
