Staphylococcus

Staphylococcus is a genus of Gram-positive, spherical bacteria in the family Staphylococcaceae. Cells occur singly, in pairs, tetrads, short chains, and characteristically in irregular, grape-like clusters. Most species are non-motile, non-spore-forming, and facultatively anaerobic. The name derives from the Ancient Greek words σταφυλή (staphylē), meaning “bunch of grapes”, and κόκκος (kokkos), meaning “berry” or “grain”, referring to the characteristic cellular arrangement. Alexander Ogston first described clustered cocci in pus from a surgical abscess, and Friedrich Julius Rosenbach subsequently established the genus and distinguished S. aureus from the organism now known as S. epidermidis. The genus contains commensal organisms of the skin and mucous membranes of humans and other animals, as well as opportunistic pathogens. S. aureus can cause community- and healthcare-associated infections, and antibiotic-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA) can cause serious disease.