Copper is a redox active metal that is essential for biological function. Copper is potentially toxic; thus, its homeostasis is carefully regulated through a system of protein transporters. Copper is taken up across the lumen surface of the small intestinal microvilli as cuprous ion by Ctr1. Cupric ion may also be taken up, but those processes are less well understood. Within the cell, intestin...

BACKGROUND Wilson's disease (WD) is a genetic disorder involving the metabolism of copper. WD patients exhibit a wide range of disease phenotypes, including Kayser-Fleischer rings in the cornea, predominant progressive hepatic disease, neurological diseases, and/or psychiatric illnesses, among others. Patients with exon12 mutations of the ATP7B gene have progressive hepatic disease. An ATP7B ge...

The cellular machinery responsible for copper-stimulated delivery of the Wilson Disease protein ATP7B to the apical domain of hepatocytes is poorly understood. We demonstrate that myosin Vb regulates the copper-stimulated delivery of ATP7B to the apical domain of polarized hepatic cells, and that disruption of the ATP7B-myosin Vb interaction reduces ATP7B apical surface expression. Myosin Vb ta...

In P-type ATPases, the nucleotide-binding (N) domain is located in the middle of the sequence which folds into the phosphorylation (P) domain. The N domain of ZntA, a Zn2+-translocating P-type ATPase from Escherichia coli, is approx. 13% identical with the N domain of sarcoplasmic reticulum Ca2+-ATPase. None of the Ca2+-ATPase residues involved in binding of ATP are found in ZntA. However, the ...

Sulfate-reducing bacterial communities from coastal sediments with a long-term exposure to copper (Cu)-mining residues were studied in lactate enrichments. The toxicity of excess copper may affect sulfate-reducing bacterial communities. Sulfate reduction was monitored by sulfate and organic acid measurements. Molecular diversity was analyzed by 16S rRNA, dissimilatory sulfate reduction dsrAB, a...

P1B-type ATPases transport heavy metal ions across cellular membranes. Archaeoglobus fulgidus CopB is a member of this subfamily. We have cloned, expressed in Escherichia coli, and functionally characterized this enzyme. CopB and its homologs are distinguished by a metal binding sequence Cys-Pro-His in their sixth transmembrane segment (H6) and a His-rich N-terminal metal binding domain (His-N-...