We cloned, expressed, and characterized a hemeprotein from Deinococcus radiodurans (D. radiodurans NO synthase, deiNOS) whose sequence is 34% identical to the oxygenase domain of mammalian NO synthases (NOSoxys). deiNOS was dimeric, bound substrate Arg and cofactor tetrahydrobiopterin, and had a normal heme environment, despite its missing N-terminal structures that in NOSoxy bind Zn(2+) and te...

Deinoxanthin (DX) is a unique carotenoid synthesized by Deinococcus radiodurans, one of the most radioresistant organisms known. In comparison with other carotenoids, DX was proven to exhibit significantly stronger reactive oxygen species (ROS)-scavenging activity, which plays an important role in the radioresistance of D. radiodurans. In this work, to gain deeper insights into the strong antio...

Deinococcus radiodurans is able to resist and survive extreme DNA damage induced by ionizing radiation and many other DNA-damaging agents. It is believed that it possesses highly efficient DNA repair mechanisms. To characterize the repair pathway of oxidized purines in this bacteria, we have purified, from crude extracts, proteins that recognize these oxidized bases. We report here that D. radi...

Ever since the discovery of the role of bacteriophytochrome (BphP) in inducing carotenoid synthesis in Deinococcus radiodurans in response to light the role of BphPs in other non-photosynthetic bacteria is not clear yet. Azospirillum brasilense, a non-photosynthetic rhizobacterium, harbours a pair of BphPs out of which AbBphP1 is a homolog of AtBphP1 of Agrobacterium tumefaciens. By overexpress...

The bacterium Deinococcus radiodurans exhibits an extreme resistance to ionizing radiation. A small subset of Deinococcus genus-specific genes were shown to be up-regulated upon exposure to ionizing radiation and to play a role in genome reconstitution. These genes include an SSB-like protein called DdrB. Here, we identified a novel protein encoded by the dr1245 gene as an interacting partner o...

The Deinococcus radiodurans SSB protein has an occluded site size of 50 +/- 2 nucleotides on ssDNA but can form a stable complex with a 26-30-nucleotide oligodeoxynucleotide using a subset of its four ssDNA binding domains. Quantitative estimates of D. radiodurans SSB protein in the D. radiodurans cell indicate approximately 2500-3000 dimers/cell, independent of the level of irradiation. At bio...

Here, we have developed an extremely efficient in vivo Tn5-based mutagenesis procedure to construct a Deinococcus radiodurans insertion mutant library subsequently screened for sensitivity to genotoxic agents such as γ and UV radiations or mitomycin C. The genes inactivated in radiosensitive mutants belong to various functional categories, including DNA repair functions, stress responses, signa...

The bacterium Deinococcus (formerly Micrococcus) radiodurans and other members of the eubacterial family Deinococaceae are extremely resistant to ionizing radiation and many other agents that damage DNA. Stationary phase D. radiodurans exposed to 1.0-1.5 Mrad gamma-irradiation sustains > 120 DNA double-strand breaks (dsbs) per chromosome; these dsbs are mended over a period of hours with 100% s...

The bacterium Deinococcus radiodurans is a champion of extreme radiation resistance that is accounted for by a highly efficient protection against proteome, but not genome, damage. A well-protected functional proteome ensures cell recovery from extensive radiation damage to other cellular constituents by molecular repair and turnover processes, including an efficient repair of disintegrated DNA...

RNA protection experiments and the crystal structure of a complex of the large ribosomal subunit from the eubacterium Deinococcus radiodurans with rapamycin, a polyketide compound resembling macrolides and ketolides, showed that rapamycin binds to a crevice located at the boundaries of the nascent protein exit tunnel, near its entrance. At this location rapamycin cannot occlude the ribosome exi...