The essential micronutrient copper is tightly regulated in organisms, as environmental exposure or homeostasis defects can cause toxicity and neurodegenerative disease. The principal target(s) of copper toxicity have not been pinpointed, but one key effect is impaired supply of iron-sulfur (FeS) clusters to the essential protein Rli1 (ABCE1). Here, to find upstream FeS biosynthesis/delivery pro...

Three strains of heterotrophic denitrifying bacteria were cultured in artificial seawater medium under trace metal clean conditions to investigate their physiological response to changes in copper concentration. Decreasing the copper concentration in cultures of Pseudomonas stutzeri and Paracoccus denitrificans resulted in accumulation of nitrous oxide (N2O) gas compared to copper-replete cultu...

The aim of this study was to determine whether total copper or soluble copper concentration is associated with gastrointestinal signs and symptoms. Forty-five healthy adult women (18-55 years of age), living in Santiago, Chile, ingested tap water with 5 mg/L of copper containing different ratios of soluble copper (copper sulfate) and insoluble copper (copper oxide) over a 9-week period. Three r...

Copper uptake and subsequent delivery to copper-dependent enzymes are essential for many cellular processes. However, the intracellular levels of this nutrient must be controlled because of its potential toxicity. The hCtr1 protein functions in high affinity copper uptake at the plasma membrane of human cells. Recent studies have shown that elevated copper stimulates the endocytosis and degrada...

Copper effects on human health represent a relevant issue in modern nutrition. One of the difficulties in assessing the early, acute effects of copper ingested via drinking water is that the taste of copper may influence the response and the capacity to taste copper in different waters is unknown. The purpose of the study was to determine the taste threshold of copper in different types of wate...

The critical developmental and genetic requirements of copper metabolism during embryogenesis are unknown. Utilizing a chemical genetic screen in zebrafish, we identified small molecules that perturb copper homeostasis. Our findings reveal a role for copper in notochord formation and demonstrate a hierarchy of copper metabolism within the embryo. To elucidate these observations, we interrogated...

Copper in biological systems presents a formidable problem: it is essential for life, yet highly reactive and a potential source of cell damage. Tight control of copper is thus a cellular necessity. To meet this challenge, cells have evolved pumps for transmembranous transport, chaperones for intracellular routing, oxidases and reductases to change the oxidation state of copper, and regulators ...

In addition to copper bound to ceruloplasmin and to albumin, there is a third small fraction of copper in human serum that is bound to amino acids. The amino acid-bound fraction of copper is in equilibrium with albumin-bound copper, and both fractions are probably in equilibrium with ionic copper. Of the 23 amino acids that are known to be in human serum, a substantial number were shown (in phy...

Three methods of copper supplementation were compared in 9to 15-month-old Friesian bulls on a farm with a history of copper deficiency. A group of 60 bulls grazed 19 ha which had been topdressed in May with 120 kg copper sulphate (6.3 kg/ha). Five of the bulls were identified for repeated sample collection. A second group of 60 bulls grazed an untreated area and five of these were each given a ...