Staphylococcus aureus RF122

Staphylococcus_aureus
Names Staphylococcus aureus RF122
Accession numbers NC_007622
Background As a pathogen, it is important to understand the virulence mechanisms of Staphylococcus in order to successfully combat the pathogen. Strains of Staphylococcus resistant to our most powerful antibiotics have increased pressure on researchers to find alternative, more effective ways of fighting Staphylococcus.Staphylococci are spherical Gram-positive bacteria, which are immobile and form grape-like clusters. They form bunches because they divide in two planes as opposed to their close relatives streptococci which, although they are similarly shaped, form chains because they divide only in one plane. Staphylococci are facultative anaerobes. They mainly grow by aerobic respiration, or fermentation that produces lactic acid.There are two different types of colonies formed. Those formed by S. aureus are yellow and become rather large on a rich medium, while those of S. epidermidis are white and form relatively small colonies, even on a rich medium.Staphylococcus aureus is a normal inhabitant of the skin and mucous membranes in the nose of a healthy human, while S. epidermidis inhabits only the skin of healthy humans.Staphylococcus usually only infects immunocompromised humans, and is an extremely versatile pathogen. Infections usually remain localized at the point of entry by host defenses. S. aureus is one of the major causes of hospital-aquired infection. Foreign bodies, such as sutures, indwelling catheters, and implanted joints, are extremely susceptible to Staphylococcus epidermidis colonization, and often serve as the point of entry for infection. Another common path of infection is the respiratory tract, where the bacterium causes pneumonia. By forming biofilms Staphylococcus epidermidis is resistant to antibiotics, antibodies, and phagocytosis, and can serve as a reservoir for antibiotic resistant genes that can be transferred to other bacteria. Other diseases caused by staphylococci include boils, sinusitis, emesis, diarrhea, endocarditis, scalded skin syndrome, osteomyelitis, urinary tract infection, and toxic shock syndrome.During the 1970s a strain of Staphylococcus aureus resistant to the antibiotic meticillin, was isolated and consequently vancomycin (the most powerful antibiotic in our arsenal) became the primary antibiotic used to combat staphylococcus infection. In 1997 a strain of S. aureus resistant to vancomycin was isolated, and people are once again exposed to the threat of untreatable staphylococcus infection. The sequencing of the S. aureus genome will hopefully provide insight into how the organism generates such a variety of toxins, and aid researchers in developing ways of combating the versatile bacterium.(From http://microbewiki.kenyon.edu/index.php/Staphylococcus) (MicrobeWiki: Staphylococcus)
Taxonomy
Kingdom:Bacteria
Phylum:Firmicutes
Class:Bacilli
Order:Bacillales
Family:Staphylococcaceae
Genus:Staphylococcus
Species:aureus
Strain RF122
Complete Yes
Sequencing centre (05-APR-2005) Herron-Olson L.L., Biomedical Genomics Center, University of Minnesota, 1500 Gortner Ave, St. Paul, MN,
(26-NOV-2005) National Center for Biotechnology Information, NIH, Bethesda, MD 20894, USA
Sequencing quality Level 6: Finished
Sequencing depth NA
Sequencing method NA
Isolation site cow presenting with clinical mastitis in 1993
Isolation country Ireland
Number of replicons 1
Gram staining properties Positive
Shape Cocci
Mobility No
Flagellar presence No
Number of membranes 1
Oxygen requirements Facultative
Optimal temperature 30.0
Temperature range Mesophilic
Habitat HostAssociated
Biotic relationship Free living
Host name Bos taurus (cow), Homo sapiens
Cell arrangement Clusters, Pairs, Singles
Sporulation Nonsporulating
Metabolism NA
Energy source NA
Diseases Mastitis
Pathogenicity No?