Copper is essential for healthy cellular functioning, but this heavy metal quickly becomes toxic when supply exceeds demand. Marine sediments receive widespread and increasing levels of copper contamination from antifouling paints owing to the 2008 global ban of organotin-based products. The toxicity of copper will increase in the coming years as seawater pH decreases and temperature increases....

Dissimilatory nitrite reductase was isolated from extracts of Alcaligenes xylosoxidans subsp. xylosoxidans (N.C.I.M.B. 11015), after activation of crude extracts by the addition of copper(II) sulphate. The enzyme was purified by a combination of (NH4)2SO4 fractionation and cationic-exchange chromatography to 93% homogeneity as judged by SDS/PAGE. SDS/PAGE and spray m.s. showed that the enzyme h...

Abstract Gold parting enabled the production of very pure gold for various purposes from sixth century BC onwards, but analytical proof this pyrotechnical process is difficult. We describe a new approach identification purified combining silver and copper isotopic with trace element analyses. Parting experiments were performed gold-silver-copper alloys using classical salt cementation to invest...

Activated oxygen intermediates during copper zinc superoxide dismutase (SOD) catalysis were investigated using an isotope fractionation technique and natural abundance reagents. Competitive oxygen kinetic isotope effects (KIEs) are reported for the enzyme-catalyzed disproportionation of superoxide as well as the stoichiometric reaction of reduced SOD with molecular oxygen. Analysis within the c...

A rabbit cytochrome P-450llE2 full-length cDNA was cloned into a yeast episomal plasmid (YEp13) between the copper-responsive yeast metallothionein gene promoter (CUP7) and the iso-I-cytochrome c gene terminator (CYCI), and the cytochrome P-450 was expressed in Saccharomyces cerevisiae. The microsomal fraction prepared from copper-treated cells exhibited a ferrous carbonyl difference spectrum w...

The prion protein (PrP(C)) is a copper-binding protein of unknown function that plays an important role in the etiology of transmissible spongiform encephalopathies. Using morphological techniques and synaptosomal fractionation methods, we show that PrP(C) is predominantly localized to synaptic membranes. Atomic absorption spectroscopy was used to identify PrP(C)-related changes in the synaptos...

background: there are varieties of purification techniques for separation of human plasma proteins such as salting out, ion exchange chromatography, and ethanol fractionation. there are limitations for each method, for example in salting out method, the salt has to be removed in an additional step. ion exchange chromatography is difficult for scaling up, and plasma fractionation is a time consu...