Query: NC_010079:575123 Staphylococcus aureus subsp. aureus USA300_TCH1516, complete
Lineage: Staphylococcus aureus; Staphylococcus; Staphylococcaceae; Bacillales; Firmicutes; Bacteria
General Information: USA300, a methicillin resistant strain of Staphylococcus aureus, has been implicated in epidemiologically unassociated outbreaks of skin and soft tissue infections among healthy individuals in at least 21 U.S. states, Canada and Europe. USA300 is also noted for its strong association with unusually invasive disease, including severe septicemia, necrotizing pneumonia and necrotizing fasciitis. Causes skin infections. Staphylcocci are generally found inhabiting the skin and mucous membranes of mammals and birds. Some members of this genus can be found as human commensals and these are generally believed to have the greatest pathogenic potential in opportunistic infections. This organism is a major cause of nosocomial (hospital-acquired) and community-acquired infections. S. aureus continues to be a major cause of mortality and is responsible for a variety of infections including, boils, furuncles, styes, impetigo and other superficial skin infections in humans. Also known to cause more serious infections particularly in the chronically ill or immunocompromised. The ability to cause invasive disease is associated with persistance in the nasal cavity of a host.
Subject: NC_010117:285230 Coxiella burnetii RSA 331, complete genome
Lineage: Coxiella burnetii; Coxiella; Coxiellaceae; Legionellales; Proteobacteria; Bacteria
General Information: This strain (RSA 331; Hentzerling) is associated with acute Q fever and was isolated from the blood of an infected patient in northern Italy in 1945. This organism is widely distributed in nature and can cause infections in reptiles, birds, and mammals. It causes Q fever, or 'query' fever, an atypical pneumonia first associated with abattoir workers in Australia. Transmission may be through insect vectors such as ticks that have bitten an infected wild or domesticated animal, or through an aerosol produced by domesticated animals such as sheep or cattle. The presence of a plasmid is believed to be associated with virulence and pathogenicity, however C. burnetii isolates containing plasmid QpDG are avirulent in guinea pigs and plasmidless isolates have been associated with endocarditis in humans. Coxiella burnetii has a developmental life cycle, and can grow vegetatively through binary fission, or asymmetrically and produce a spore-like cell. The spore-like cell may enable the organism to exist extracellularly for small amounts of time. This bacterium is an obligate intracellular pathogen. It is endocytosed by a host cell, a macrophage for example, and lives and replicates inside the phagolysozome, a unique property of this organism. The genome encodes proteins that have a higher than average pI, which may enable adaptation to the acidic environment of the phagolysozome. The chromosome also contains genes for a number of detoxification and stress response proteins such as dismutases that allow growth in the oxidative environment. The type IV system is similar to the one found in Legionella, which may be important for intracellular survival. This organism produces numerous ankyrin-repeat proteins that may be involved in interactions with the host cell. The genome has 83 pseudogenes, which may be a result of the typical genome-wide degradation observed with other intracellular organisms and also has a group I intron in the 23S ribosomal RNA gene.