Staphylococcus Aureus: Structure and Functions

Staphylococcus Aureus: Structure and Functions Introduction 1.1 Staphylococcus aureus Staphylococcus aureus is an opportunistic yet versatile pathogen that can infect almost all types of tissue in the human body. 33-50% of healthy individuals were reported to be S. aureus carriers. The diseases resulting from S. aureus infection range from superficial infections; invasive infections such as endocarditis to the life threatening septic shock and toxic shock. The presence of foreign material greatly increases the risk of infection by providing a base for attachment and biofilm formation. S. aureus appears as clustered gram positive cocci under the microscope. Criteria used to identify this organism include the production of golden pigment on nutrient agar; being positive for coagulase; mannitol fermentation and the production of deoxyribonuclease. The virulence of the infecting strain and the nature of the host immune response are important determinants for the outcome of severe S. aureus infection . 1.1.1 S. aureus genome and regulation of gene expression S. aureus has a 2.8-2.