Disease relevance of dioxouranium

• A Citrobacter sp. accumulates uranyl ion (UO2(2+)) as crystalline HUO2PO4.4H2O (HUP), using enzymatically generated inorganic phosphate [1].
• In closed systems, sulfate-reducing bacteria (SRB) such as Desulfovibrio spp. demonstrably affect U immobilization by enzymatic reduction of U(VI) species (primarily the uranyl ion, UO2(2+), and its complexes) to U(IV) [2].
• Binding sites of sorbed uranyl ion in the cell wall of Mycobacterium smegmatis [3].
• When the proportion of UO2(2+) was regressed against U toxicity, a very strong, positive relationship was observed (r2 = 1, n = 4, P < 0.001) [4].
• The biosorption for La2+, Co2+, Mn2+, UO2(2+), Pb2+, Ag+, Zn2+, Cd2+ and Cr2+ by wet and dry biomass form Myxococcus xanthus obtained from laboratory cultures and Saccharomyces cerevisiae from the brewing industry has been studied [5].

High impact information on dioxouranium

• This suggests the presence of a tight binding site for the uranyl ion in the junction [6].
• Analogous to K+ activation, UO2(2+) predominantly inhibits AdoMet formation rather than tripolyphosphate hydrolysis [7].
• We submit that in frog skin two cation-selective channels occur, distinguished by their spontaneous gating kinetics, their sensitivity to UO2(2+), and their permeability for Cs+ [8].
• Using tetracaine and UO2(2+) as channel-specific compounds, we demonstrated with microelectrode measurements that both channel types are located in the granulosum cells [9].
• Nuclear magnetic resonance and calorimetric study of the structure, dynamics, and phase behavior of uranyl ion/dipalmitoylphosphatidylcholine complexes [10].

Chemical compound and disease context of dioxouranium

• Recombinant Escherichia coli DH5 alpha bearing cloned phoN or the related phoC acquired metal-accumulating ability, which was compared with that of the Citrobacter sp. with respect to removal of uranyl ion (UO2(2+)) from dilute aqueous flows and its deposition in the form of polycrystalline hydrogen uranyl phosphate (HUO2PO4) [11].

Biological context of dioxouranium

• Reusable photonucleases: plasmid scission by a uranyl ion impregnated adenine homopolymer in the presence of visible light and sunlight [12].
• At each of the concentrations used, uranyl ion did not have any detectable effect on the actual shape of the action potential itself [13].
• In addition, the combined treatment of the diaphragm from diabetic mice with Cd2+ plus UO2(2+) in 0.25 mmol/l Ca2+ Krebs solution and then stepwise replenishment of Ca2+ led to a greater restoration of muscle contractions at a lower cumulative Ca2+ concentration than that was found with the normal diaphragm.(ABSTRACT TRUNCATED AT 250 WORDS)[14]
• Experiments were performed in which the uranyl ion, UO2(2+) (U(VI)), at various concentrations was present during manganese oxide biogenesis [15].
• In addition, the use of sodium carbonate as a desorbent agent is discussed where it was possible to recover up to 94,53% of UO2(2+) by both M. xanthus and S. cerevisiae biomass [5].

Anatomical context of dioxouranium

• It is suggested that the architecture of the bacterial cell surface provides a means of access of uranyl ion to the inner and outer membranes and enzymically liberated phosphate in a way that minimizes fouling in whole cells [16].
• The uranyl ion (UO2(2+)) produces rhythmic contractions of the longitudinal muscle of the ileum, similar to those induced by repetitive transmural stimulation [17].
• Hexamethonium inhibited the action of UO2(2+), indicating a preganglionic site of action of UO2(2+) and interneurons possibly being involved in the ACh-releasing effect of UO2(2+) [17].
• Mode of inhibitory action of Zn2+, Hg2+ and UO2(2+) on 5'-nucleotidase of mouse hepatic microsomes [18].
• The adsorption of uranyl ion was rapid, selective, and mostly dependent on physico-chemical binding to the cell components [19].

Associations of dioxouranium with other chemical compounds

• Our results clearly indicate that U(VI) (as soluble uranyl ion) is readily reduced by green rust to U(IV) in the form of relatively insoluble UO2 nanoparticles, suggesting that the presence of green rusts in the subsurface may have significant effects on the mobility of uranium, particularly under iron-reducing conditions [20].
• The method is based on the decomposition of lactate in the presence of UO2(2+) and Fe3+ upon irradiation with UV or visible light [21].
• Collision-induced dissociation tandem mass spectrometry of desferrioxamine siderophore complexes from electrospray ionization of UO2(2+), Fe3+ and Ca2+ solutions [22].
• PANSIL is highly effective at sequestering UO2(2+) from solution when the pH is between about 5 and 8 and can preferentially sequester UO2(2+) from solutions that are typical of the groundwater from a mine tailings site, due to the stability of the polyacryloamidoxime uranyl complex formed [23].
• The effects of uranyl ion (UO22+; at low concentrations binds specifically to phosphate groups) and the cationic dye methylene blue (MB+; binds strongly to carboxyl groups) on saxitoxin (STX) potency in crayfish axon has been studied by means of intracellular microelectrodes [24].

Gene context of dioxouranium

• In addition, computer simulations of the 31P-, 13C-, and 2H-NMR powder spectra show that axial diffusion of the DPPC molecules about their long axes is quenched by addition of UO2(2+) and acyl chain isomerization is the dominant motional mode [10].
• The geometries and energies of dioxouranium(VI) complexes in the gas phase and solvent models differ slightly, with differences in bond distance and energy of typically less than 0.06 A and 10 kJ/mol, respectively [25].
• Metal-peptide complexes in a 1:1 ratio between the uranyl cation (UO2(2+)) and the peptides, DAHK or GGH, are observed in the gas phase (ESI-MS) [26].
• We report a molecular dynamics study of the solvation of the UO2(2+) and Eu3+ cations and their chloro complexes in the [BMI][PF6][H2O] "humid" room-temperature ionic liquid (IL) composed of 1-butyl-3-methylimidazolium+ and PF6- ions and H2O in a 1:1:1 ratio [27].
• After enrichment on this matrix flame AAS has been used to determine these metal ions (except the uranyl ion) in river water samples (RSD < or = 6.5%); fluorimetry was used to determine uranyl ion in well water samples (RSD < or = 6.3%) [28].

Analytical, diagnostic and therapeutic context of dioxouranium

• UO2(2+) remains a tight-binding inhibitor of the E42Q mutant, which suggests that K+ and UO2(2+) have different ligation preferences when bound in the monovalent cation binding pocket [7].
• Solution chemistry of uranyl ion with iminodiacetate and oxydiacetate: A combined NMR/EXAFS and potentiometry/calorimetry study [29].
• Dioxouranium together with copper(II), nickel(II) and iron(II) were extracted in chloroform as complexes of bis(salicylaldehyde)-dl-stilbenediimine (dl-H2SA2S) or bis(salicylaldehyde)-meso-stilbenediimine (meso-H2SA2S), and separated by liquid chromatography with UV detection [30].

References