The aim of the present work was to engineer bacteria for the removal of Co in contaminated effluents. Radioactive cobalt ((60)Co) is known as a major contributor for person-sievert budgetary because of its long half-life and high γ-energy values. Some bacterial Ni/Co transporter (NiCoT) genes were described to have preferential uptake for cobalt. In this study, the NiCoT genes nxiA and nvoA from Rhodopseudomonas palustris CGA009 (RP) and Novosphingobium aromaticivorans F-199 (NA), respectively, were cloned under the control of the groESL promoter. These genes were expressed in Deinococcus radiodurans in reason of its high resistance to radiation as compared to other bacterial strains. Using qualitative real time-PCR, we showed that the expression of NiCoT-RP and NiCoT-NA is induced by cobalt and nickel. The functional expression of these genes in bioengineered D. radiodurans R1 strains resulted in >60 % removal of (60)Co (≥5.1 nM) within 90 min from simulated spent decontamination solution containing 8.5 nM of Co, even in the presence of >10 mM of Fe, Cr, and Ni. D. radiodurans R1 (DR-RP and DR-NA) showed superior survival to recombinant E. coli (ARY023) expressing NiCoT-RP and NA and efficiency in Co remediation up to 6.4 kGy. Thus, the present study reports a remarkable reduction in biomass requirements (2 kg) compared to previous studies using wild-type bacteria (50 kg) or ion-exchanger resins (8000 kg) for treatment of ~10(5)-l spent decontamination solutions (SDS).

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Mycobacterium is immovable induce aerobic, acid-fast gram-positive bacilli with high genomic content (59-66%). In the operon structure frequently establish for the genes of three molecular components: the ABC-binding protein, the membrane protein, and the substrate-binding protein, the rates of multidrug resistant and metal ions. The main objective of this study was to analyze the metal ions from fi ve Mycobacterium species and to identify the metal transporters with "Genomic Island" associated features, in-silico analysis allowed identifi cation of metal and drug transporters, phylogenetic analysis, genomic island path analysis, prediction of interacting metal ions, 3D structure, domain analysis and for the NiCoT metal transporter from Mycobacterium tuberculosis. These data are the fi rst results of a big frame project that aims to accelerate the prioritizing of gene candidates that control element accumulation by taking advantage of high-throughput. The present in-silico study reveals the complete suite of NiCoT Metal Transporter in Mycobacterium tuberculosis H37Rv, which is involved in urease enzyme activity and biological function. The STRING analysis defi nes that the functional partners involved in transport of metal ions. While high expression yields of membrane proteins remain signifi cant bottleneck for many proteins.