Query: NC_010263:278463 Rickettsia rickettsii str. Iowa, complete genome
Lineage: Rickettsia rickettsii; Rickettsia; Rickettsiaceae; Rickettsiales; Proteobacteria; Bacteria
General Information: Causative agent for Rocky Mountain Spotted Fever. This organism was first identified by Dr. Howard Rickets as the causative agent of Rocky Mountain Spotted Fever, which was originally named for its geographic distribution at the time, it is now known to be widespread throughout the North American continent. This bacterium is an obligate intracellular pathogen that infects primarily the vascular endothelium, and occasionally smooth muscle tissue. It is passed to the human host from a tick bite, and the tick acts as both a natural reservoir and a vector for disease transmission. Once the organism is endocytosed by the host cell, it quickly escapes the phagozome, and replicates intracellularly, causing cell death and tissue damage. The disease is characterized by a spotted rash and has a high mortality rate if left untreated.
Subject: NC_001263:243000 Deinococcus radiodurans R1 chromosome 1, complete sequence
Lineage: Deinococcus radiodurans; Deinococcus; Deinococcaceae; Deinococcales; Deinococcus-Thermus; Bacteria
General Information: This red-pigmented organism's name means "strange berry that withstands radiation", marking the fact that this organism is one of the most radiation-resistant known. It can tolerate radiation levels at 1000 times the levels that would kill a human and it was originally isolated in 1956 from a can of meat that had been irradiated with X-rays. The resistance to radiation may reflect its resistance to dessication, which also causes DNA damage. This organism may be of use in cleaning up toxic metals found at nuclear weapons production sites due to the radiation resistance. This bacterium is also a highly efficient transformer, and can readily take up exogenous DNA from the environment, which may also aid DNA repair. This organism carries multiple copies of many DNA repair genes, suggesting a robust system for dealing with DNA damage. The recombination system may rely on multiple copies of various repeat elements found throughout the genome.