ModA, the periplasmic-binding protein of the Escherichia coli mod transport system was overexpressed and purified. Binding of molybdate and tungstate to ModA was found to modify the UV absorption and fluorescence emission spectra of the protein. Titration of these changes showed that ModA binds molybdate and tungstate in a 1:1 molar ratio. ModA showed an intrinsic fluorescence emission spectrum...

In this paper, a novel nanophosphor, Y10W2O21:Eu, was synthesized through co-precipitation which is a simple and low-costing method. The structure and morphology of the nanocrystal samples were characterized by using XRD and FE-SEM. The emission spectra, excitation spectra and fluorescence decay curves were measured. J-O parameters, quantum efficiencies of Eu3+ 5D0 energy level, color coordinat...

Transport across cellular membranes is an essential process that is catalyzed by diverse membrane transport proteins. The turnover rates of certain transporters are inhibited by their substrates in a process termed trans-inhibition, whose structural basis is poorly understood. We present the crystal structure of a molybdate/tungstate ABC transporter (ModBC) from Methanosarcina acetivorans in a ...

Sodium tungstate has been found to correct hyperglycemia in insulin- and noninsulin-dependent models of diabetes when administered in drinking fluid with a low degree of toxicity; thus, it provides a potential treatment for diabetes. In the present report, pharmacokinetic studies with sodium tungstate were carried out in the Sprague-Dawley rat and beagle dog. This drug was administered either i...

Tungsten trioxide (WO(3)) nanostructures were synthesized by hydrothermal method using sodium tungstate (Na(2)WO(4).2H(2)O) alone as starting material, and sodium tungstate in presence of ferrous ammonium sulfate [(NH(4))(2)Fe(SO(4))(2).6H(2)O] or cobalt chloride (CoCl(2).6H(2)O) as structure-directing agents. Orthorhombic WO(3) having a rectangular slab-like morphology was obtained when Na(2)W...

Growth of five strains of sulfur-oxidizing bacteria Acidithiobacillus thiooxidans, including strain NB1-3, was inhibited completely by 50 microM of sodium tungstate (Na(2)WO(4)). When the cells of NB1-3 were incubated in 0.1 M beta-alanine-SO(4)(2-) buffer (pH 3.0) with 100 microM Na(2)WO(4) for 1 h, the amount of tungsten bound to the cells was 33 microg/mg protein. Approximately 10 times more...

Bismuth complex oxides, in particular, bismuth tungstate, have recently attracted attention as promising photocatalytic materials for water treatment processes. In the present work, photocatalytic bismuth tungstate films were prepared by pulsed direct current (DC) reactive magnetron sputtering of Bi and W targets in an Ar/O2 atmosphere onto spherically-shaped glass beads. The uniform coverage o...

Microstructured Y2WO6 materials were prepared in a hydrothermal synthesis in the presence of glycerol, which was employed as both a solvent and a structure directing agent, after which they were heat treated at 1100 °C. These materials, similar to other previously reported Y2WO6 as well as other rare-earth tungstate structures, showed interesting luminescence properties. Six Ln(3+) doped or co-...

After 3 years of extensive R&D the Bogoroditsk Techno-Chemical Plant in Russia is ready to enter a preproduction phase where 6000 Lead Tungstate crystals will be produced for the CMS electromagnetic calorimeter during a period of about 18 months. Although this is a demonstration test for the mass production, these crystals will have to be installed in the calorimeter and have therefore to compl...