Query: NC_001263:2461941 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.
Subject: NC_012560:3505235 Azotobacter vinelandii DJ, complete genome
Lineage: Azotobacter vinelandii; Azotobacter; Pseudomonadaceae; Pseudomonadales; Proteobacteria; Bacteria
General Information: This organism was first isolated from the soil in Vineland, New Jersey, although it is found worldwide. It is a large obligate aerobe that has one of the highest respiratory rates of any organism. Azotobacter vinelandii also produces a number of unusual nitrogenases which allow it to fix atmospheric nitrogen to ammonia, a compound it can then use as a nitrogen source. It protects the oxygen-sensitive nitrogenase enzymes through its high respiratory rate, which sequesters the nitrogenase complexes in an anoxic environment. This organism has a number of unusual characteristics. Under extreme environmental conditions, the cell will produce a cyst that is resistant to dessication and is surrounded by two capsular polysaccharide layers. This organism produces two industrially important polysaccharides, poly-beta-hydroxybutyrate (PHB) and alginate. PHB is a thermoplastic biopolymer, and alginate is used in the food industry. Alginate is also used by the pathogen Pseudomonas aeruginosa to infect the lungs of cystic fibrosis patients.