The electrodeposition of iron and Zn-Fe alloys on polycrystalline nickel was investigated in the 40.0-60.0 mol % zinc chloride1-ethyl-3-methylimidazolium chloride ionic liquid containing iron~II! at 90°C. Iron~II! was electrochemically reduced to iron metal before the reduction of zinc~II! to zinc metal, and anomalous codeposition of Zn-Fe did not occur in this ionic liquid. Underpotential depo...

Human carbonic anhydrase II (HCA II) has a histidine at position 64 (His64) that donates a proton to the zinc-bound hydroxide in catalysis of the dehydration of bicarbonate. To examine the effect of the histidine location on proton shuttling, His64 was replaced with Ala and Thr200 replaced with histidine (H64A-T200H HCAII), effectively relocating the proton shuttle residue 2 A closer to the zin...

The x-ray absorption fine structure (XAFS) zinc K-edge steps for intact stages I,II and V,VI Xenopus laevis oocytes demonstrate that the zinc concentration is about 3 and 1 mM, respectively. However, the chi(k) function for the early stage oocytes differs markedly from that for the late one. Analysis of the XAFS data for stage I,II oocytes indicates that zinc is bound to 2.0 +/- 0.5 sulfur atom...

This study examines zinc(II)–chitosan complexes as a bio-sorbent for phosphate removal from aqueous solutions. The bio-sorbent is prepared and is characterized via Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), and Point of Zero Charge (pHPZC)–drift method. The adsorption capacity of zinc(II)–chitosan bio-sorbent is compared with those of chitosan and ZnO–c...

Bacteria respond dynamically to the changes in zinc availability. Repression by the Bacillus subtilis transcription factor Zur requires Zn(II), which binds with negative cooperativity to two regulatory sites per dimer to form, sequentially, Zur2:Zn3 and Zur2:Zn4 forms of the repressor. Here we show that, as cells transition from zinc sufficiency to deficiency, operons regulated by Zur are derep...

Assessment of adsorption zinc (II) ions from aqueous solution using alginate-SBA-15 sorbent nanocomposite was investigated as a function of zinc concentration, solution pH, and contact time. For that purpose, the alginate-SBA-15 nanocomposite adsorbent was prepared through encapsulation method by immobilization mesoporous SBA-15 into a polymeric matrix. Identification of functional groups and s...

L–Arabinose-based coordination polymers were synthesized by the oxidation of L–arabinose using warm HNO3 to form arabinaric acid and allowing the resulting arabinaric acid to react with the different metal ions such as zinc(II), lead(II), copper(II), iron(III), and chromium(III). Only zinc(II) and lead(II) ions produced crystalline coordination polymers suitable for analysis while copper(II) pr...

Glutamate carboxypeptidase II (GCP II) catalyzes the extracellular hydrolysis of the neuromodulator N-acetyl-aspartylglutamate to N-acetyl-aspartate and glutamate. GCP II also hydrolyzes gamma-glutamyl bonds in folylpolyglutamate. The predicted amino acid sequence of GCP II displays similarities to aminopeptidases from Streptomyces griseus and Vibrio proteolyticus, whose crystal structures have...

The G-protein coupled receptor 83 (GPR83) is an orphan G-protein coupled receptor for which the natural ligand(s) and signaling pathway(s) remain to be identified. Previous studies suggest a role of GPR83 in the regulation of thermogenesis and the control of circulating adiponectin. The aim of this study was to gain insights into the molecular underpinnings underlying GPR83 signaling. In partic...

The zinc(II) complex [Zn2(dmdtc)2(μ-dmdtc)2] has been synthesized directly from thiram ligand, containing a disulfide bond {dmdtc = N,N-dimethyldithiocarbamate; thiram = N,N-tetramethylthiuram disulfide}, and characterized by elemental analysis and spectroscopic methods. Surprisingly thiram, undergoes a reductive disulfide bond scission upon reaction with Zn2+ in methanolic media to give the [Z...