staphylococcus

staphylococcus (stăfˌələkŏkˈəs) [key], any of the pathogenic bacteria, parasitic to humans, that belong to the genus Staphylococcus. The spherical bacterial cells (cocci) typically occur in irregular clusters [Gr. staphyle = bunch of grapes]. The term staphylococcus is also sometimes used loosely for the cluster arrangement itself and, broadly, for any bacteria with such a growth pattern. The pigments produced by staphylococci are the basis of the names given to the various strains—those with colors ranging from orange to yellow are designated S. aureus ; white strains are known as S. albus.

Staphylococci cause abscesses, boils, and other infections of the skin, such as impetigo. They can also produce infection in any organ of the body (e.g., staphylococcal pneumonia of the lungs). The most common form of food poisoning is brought on by staphylococcus-contaminated food. The staphylococcus organisms also generate toxins and enzymes that can destroy both red and white blood cells.

Unlike some other types of bacteria, staphylococci are generally partly or wholly resistant to antibiotic action; this raises serious problems in the treatment and control of staphylococcus infections (see drug resistance). The rise of drug-resistant virulent strains of S. aureus, particularly methicillin-resistant S. aureus (MRSA), has led increasing concern in the medical community. Although sick patients with compromised immune systems and children are most susceptible to the strains, which most typically are contracted in hospital, nursing home, and other health-care settings, healthy persons have also been infected. Pharmaceutical companies are working to develop new antibiotics to kill drug-resistant strains of staphylococcus and other bacteria, and a vaccine for S. aureus has been developed.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.

More on staphylococcus from Fact Monster:

  • bacitracin - bacitracin bacitracin , antibiotic produced by a strain of the bacterial species Bacillus subtilis. ...
  • neomycin - neomycin neomycin , broad spectrum antibiotic effective against both gram positive and gram ...
  • sty - sty sty, in medicine, acute localized infection of one or more of the glands of the eyelid, with ...
  • toxic shock syndrome - toxic shock syndrome toxic shock syndrome (TSS). acute, sometimes fatal, disease characterized by ...
  • boil - boil boil or furuncle, tender, painful inflammatory nodule in the skin, which becomes pustular but ...

See more Encyclopedia articles on: Moneran and Protistan