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would that apply to say for instance the closed neuclear power plant we have locally..Surely there is a certain amount of waste loste here that could be benefitted if such a thing is actually possible..
Bacteria belonging to the family Deinococcaceae are some of the most radiation-resistant organisms yet discovered. Deinococcus (Micrococcus) radiodurans strain R1 (ATCC BAA-816) was first reported in 1956 by A. W. Anderson and coworkers of the Oregon Agricultural Experimental Station, Corvalis, Oregon. This obligate aerobic bacterium typically grows in rich medium as clusters of two cells (diplococci) in the early stages of growth, and as clusters of four cells (tetracocci) in the late stages of growth, is non-pathogenic, and best known for its ability to survive extremely high doses of acute ionizing radiation (10,000 Gy) without cell-killing. For comparison, 5 Gy is lethal to the average human, and 1,000 Gy can sterilize a culture of Escherichia coli. D. radiodurans is capable of growth under chronic radiation (60 Gy/hour) and resistant to other DNA damaging conditions including exposure to desiccation, UV light, and hydrogen peroxide. The genes and cellular pathways underlying the survival strategies of D. radiodurans are under investigation, and its resistance characteristics are being exploited in the development of bioremediation processes for cleanup of highly radioactive US Department of Energy waste sites.D. radiodurans maintains 4-8 haploid copies of its genome per cell (16-32 genomes/tetracoccus), and the repair of irradiation-induced DNA double-stranded breaks (DSBs) is known to be mediated by recA-independent (single-stranded annealing) and recA-dependent homologous recombination, but no error-prone SOS response is observed. Yet, the identity of the genetic systems underlying those repair processes in D. radiodurans remains unknown in spite of detailed global cellular analyses including whole genome sequencing and annotation, and transcriptome and proteome profiling of cells recovering from high-dose irradiation. The lack of a clearly identifiable unique DNA repair system in D. radiodurans has given rise to several competing views of the mechanisms responsible for its extraordinary survival, and research in this laboratory addresses the following possibilities: 1) There are novel repair functions encoded among hypothetical genes predicted by genomic annotation; 2) D. radiodurans uses conventional DNA repair pathways, but with much greater efficiency than other bacteria; 3) DNA repair in D. radiodurans is promoted by aggregation of its multiple chromosomes; 4) The unusual metabolic environment of D. radiodurans facilitates recovery; and 5) Intracellular Mn(II) accumulation facilitates recovery.
Abstract: This patent describes a method of extracting nickel, cobalt, and other metals, including the platinum and palladium metal families, from soil by cultivation of the soil with hyperaccumulating plants that concentrate these metals in above-ground portions of the plants. The plants can be harvested, dried, and smelted to recover the metal in a process known as metal phytomining. The applicants have screened a large wild-type collection of germplasm to identity hyperaccumulating plants. Plants of the Brassicaceae family, particularly naturally occurring plants as opposed to those with induced mutations, are known to be Ni+Co accumulators. Alyssum species that are preferred candidates for use concentrate and hyperaccumulate nickel, show an enhanced uptake of cobalt, and may be useful in accumulating other metals. Preferred species have a preference for, and a high toxicity resistance to, these metallic elements. Rather than relying on the unpredictable process of mutagenesis, the applicants have screened a large library of wild-type germplasm and have identified several Alyssum species, including A. murale, A. pintodasilvae (A. serpyllifolium ssp.), A. malacitanum, A. lesbiacum, A. tenium, and A. fallacinum as suitable hyperaccumulators of nickel and useful in the enhanced uptake of cobalt. The same plants may also accumulate Pd, Rh, Ru, Pt, Ir, Os, and Re. While these platinum and palladium metals are accumulated in lower concentrations, their greater value per unit weight makes phytomining of these metals economically attractive as well. By definition, hyperaccumulator plants accumulate over 1000 mg Ni or Co/kg dry weight growing in the soils where they evolved. The identified metal species are accumulated by growing the Alyssum in nickel-rich soil under specific soil conditions, i.e., (1) lowering the soil pH, which increases the phytoavailability of nickel, (2) maintaining moderate levels of Ca in the soil by appropriate treatments and by use of Ca, (3) using ammonium-constraining or ammonium-generating nitrogen fertilizers to improve plant growth and to increase Ni hyperaccumulation due to rhizosphere acidification, and (4) applying chelating agents to the soil to improve nickel uptake by the roots of the hyperaccumulating Alyssum species. Examples of suitable chelating agents include nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid, and ethylene glycol-bis-(beta-aminoethylether)-N,N'-tetraacetic acid.