Query: NC_002953:2773000 Staphylococcus aureus subsp. aureus MSSA476, complete genome
Lineage: Staphylococcus aureus; Staphylococcus; Staphylococcaceae; Bacillales; Firmicutes; Bacteria
General Information: This strain is a hyper-virulent community acquired methicillin-susceptible (MSSA) strain isolated in the United Kingdom. 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. 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_005945:1523014 Bacillus anthracis str. Sterne, complete genome
Lineage: Bacillus anthracis; Bacillus; Bacillaceae; Bacillales; Firmicutes; Bacteria
General Information: This strain carries the anthrax toxin plasmid pXO1 but not the capsule plasmid pXO2 and is therefore avirulent but toxigenic. It is the counterpart to the Pasteur strain that carries pXO2 but not pXO1. This strain is often used for vaccine development. Under starvation conditions this group of bacteria initiate a pathway that leads to endospore formation, a process that is thoroughly studied and is a model system for prokaryotic development and differentiation. Spores are highly resistant to heat, cold, dessication, radiation, and disinfectants, and enable the organism to persist in otherwise inhospitable environments. Under more inviting conditions the spores germinate to produce vegetative cells. This organism was the first to be shown to cause disease by Dr. Louis Pasteur (the organism, isolated from sick animals, was grown in the laboratory and then used to infect healthy animals and make them sick). This organism was also the first for which an attenuated strain was developed as a vaccine. Herbivorous animals become infected with the organism when they ingest spores from the soil whereas humans become infected when they come into contact with a contaminated animal. PA/LF and PA/EF complexes are internalized by host cells where the LF (metalloprotease) and EF (calmodulin-dependent adenylate cyclase) components act. At high levels LF induces cell death and release of the bacterium while EF increases host susceptibility to infection and promotes fluid accumulation in the cells.