Staphylococcus aureus Essay example

805 Words 4 Pages
Staphylococcus aureus

Life History and Characteristics: Staphylococcus aureus is a gram positive bacterium that is usually found in the nasal passages and on the skin of 15 to 40% of healthy humans, but can also survive in a wide variety of locations in the body. This bacterium is spread from person to person or to fomite by direct contact. Colonies of S. aureus appear in pairs, chains, or clusters. S. aureus is not an organism that is contained to one region of the world and is a universal health concern, specifically in the food handling industries.

Diseases: The most common health concern associated with S. aureus is food poisoning caused by the release of enterotoxins, even in small doses, into food. Release of less than 1
…show more content…
The release of two exotoxins from certain strains of S. aureus can lead to Staphylococcal scaled skin syndrome (SSSS), which is characterized by blistering skin. Invasion into the body can lead to more serious health problems including pneumonia (a frequent complication of influenza), mastitis, phlebitis (inflammation of the veins), meningitis, and urinary tract infections. If the bacterium is allowed to colonize even deeper tissues more serious conditions such as osteomyelitis and endocarditis may result. The most serious consequences of these deeper tissue infections occur when the bacterium invades the bloodstream leading to septic shock and possibly death.

Virulence Factors: The most important virulence factor of S. aureus is the specific surface proteins that allow the organism to attach to host proteins. The surface proteins of this bacterium allow it to attach to host proteins such as laminin and fibronectin, which form the extracellular matrix of epithelial and endothelial cells. S. aureus also produces a number of membrane damaging toxins that allow the organism to further invade and harm the host, of which the alpha- toxin is the most well studied and is the protein responsible for septic shock. The alpha- toxin is a protein that binds to a specific receptor in platelets and monocytes in humans, forming pores that eventually destroy the cell.

A second toxin that is significant in human infection is the gamma- toxin (also called leukotoxin) which

More about Staphylococcus aureus Essay example

Open Document