Pre_GI: SWBIT SVG BLASTN

Query: NC_003997:5200805 Bacillus anthracis str. Ames, complete genome

Lineage: Bacillus anthracis; Bacillus; Bacillaceae; Bacillales; Firmicutes; Bacteria

General Information: This well studied laboratory strain (Porton isolate) is not virulent due to the loss of the two plasmids, pXO1 and pXO2. 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.

Subject: NC_012633:12000 Rickettsia africae ESF-5, complete genome

Lineage: Rickettsia africae; Rickettsia; Rickettsiaceae; Rickettsiales; Proteobacteria; Bacteria

General Information: This organism was isolated from a cattle tick, Amblyomma variegatum, collected in Ethiopia. This organism, a member of the spotted fever group of the Rickettsiales, is found in sub-Saharan Africa and the Caribbean. Rickettsia africae causes a flu-like illness, characterized by a mild fever and severe headache, without the skin rash common to other spotted fever group Rickettsia species. Members of this genus, like other Rickettsial organisms such as Neorickettsia and Anaplasma, are obligate intracellular pathogens. In both groups, the bacteria are transmitted via an insect, usually a tick, to a host organism where they target endothelial cells and sometimes macrophages. They attach via an adhesin, rickettsial outer membrane protein A, and are internalized where they persist as cytoplasmically free organisms.