Despite increased interest in the role of copper deficiency in clinical problems and an increased understanding of the physiological roles of copper, the diagnosis of a marginal deficiency has not been perfected. The use of non-standardized procedures and the effects of factors other than copper nutriture have impeded identification of the "ideal" indicator of copper nutritional status in adult...

Copper is essential but can be toxic even at low concentrations. Coping with this duality requires multiple pathways to control intracellular copper availability. Three copper-inducible promoters, controlling expression of six copper tolerance genes, were recently identified in Escherichia coli. The cue system employs an inner membrane copper transporter, whereas the cus system includes a tripa...

a simple and sensitive extraction-fluorimetric method for the determination of copper is reported. the 1,7-diaza-15-crown-5-copper-rose bengal (da15c5-cu-rb) ternary complex is quantitatively extracted into chloroform, diluted with ammoniacal acetone and its fluorescence intensity is measured at 570 nm with excitation at 540 nm. a linear calibration graph was obtained over the copper concentrat...

1. Copper compounds (calcium copper edetate, copper heptanoate, copper methionate, copper chloride, copper oxide, dicopper oxide and copper gluconate) are normally used, orally in feed or in an injectable solution, to treat copper deficiency in food-producing animals. In veterinary medicine, the recommended doses are 50 to 100 mg copper per animal given as a single injection. Copper has antimic...

UNLABELLED In the absence of a tight control of copper entrance into cells, bacteria have evolved different systems to control copper concentration within the cytoplasm and the periplasm. Central to these systems, the Cu(+) ATPase CopA plays a major role in copper tolerance and translocates copper from the cytoplasm to the periplasm. The fate of copper in the periplasm varies among species. Cop...

Copper-resistant strains of Pseudomonas syringae pathovar tomato accumulate copper and develop blue colonies on copper-containing media. Three of the protein products of the copper-resistance operon (cop) were characterized to provide an understanding of the copper-resistance mechanism and its relationship to copper accumulation. The Cop proteins, CopA (72 kDa), CopB (39 kDa), and CopC (12 kDa)...

The trace element copper is vital to the healthy functioning of organisms. Copper is used in a multitude of cellular activities including respiration, angiogenesis, and immune responses. Like other metals, copper homeostasis is a tightly regulated process. Copper is transported from dietary intake through the serum and into cells via a variety of transporters. There are a variety of copper chap...

The physiological and biochemical responses of two green algae Ankistrodesmus falcatus and Chlorella vulgaris to copper sulphate were investigated. In this experiment both Ankistrodesmus and Chlorella cultures were treated with copper sulphate concentrations ranging from 0. 5 to 250 μM. The influence of copper on growth and metabolism was determined. Ankistrodesmus grown at 250 μM copper sulpha...

at the present time, flotation is the primary method for copper minerals separation from copper ores. the main copper ores that is extracted in the world is sulphide ore. the sulphide minerals are floated readily by using sulphydryl collectors. in the case of using xanthates , which are among the sulphydryl collectors, used more in the flotation of sulphide minerals of copper, the flotation of ...

Because copper catalyzes the conversion of H(2)O(2) to hydroxyl radicals in vitro, it has been proposed that oxidative DNA damage may be an important component of copper toxicity. Elimination of the copper export genes, copA, cueO, and cusCFBA, rendered Escherichia coli sensitive to growth inhibition by copper and provided forcing circumstances in which this hypothesis could be tested. When the...