Phosphoenzyme formation by purified, reconstituted copper ATPase of Enterococcus hirae.
FEBS Lett
Institute of Clinical Pharmacology, University of Berne, Switzerland.
Published: December 1996
The Enterococcus hirae CopB ATPase serves in the secretion of excess copper from cells and belongs to the recently discovered, new class of heavy metal transport ATPases. We here report the affinity purification of CopB to near homogeneity and its reconstitution into phospholipid vesicles. In these proteoliposomes, the ATPase formed an acylphosphate reaction intermediate with the gamma-phosphate of ATP. ATPase activity and phosphoenzyme formation were inhibited by vanadate with an I(50) of 0.1 mM. Our results suggest that heavy metal and non-heavy metal ATPases operate by the same underlying mechanism.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/s0014-5793(96)01306-3 | DOI Listing |
Similar Publications
Cdc14 phosphatases use an intramolecular pseudosubstrate motif to stimulate and regulate catalysis.
J Biol Chem
September 2024
Department of Biochemistry, Purdue University, West Lafayette, Indiana, USA; Institute for Cancer Research, Purdue University, West Lafayette, Indiana, USA; Institute for Drug Discovery, Purdue University, West Lafayette, Indiana, USA; Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, Indiana, USA. Electronic address:
Cdc14 phosphatases are related structurally and mechanistically to protein tyrosine phosphatases (PTPs) but evolved a unique specificity for phosphoSer-Pro-X-Lys/Arg sites primarily deposited by cyclin-dependent kinases. This specialization is widely conserved in eukaryotes. The evolutionary reconfiguration of the Cdc14 active site to selectively accommodate phosphoSer-Pro likely required modification to the canonical PTP catalytic cycle.
View Article and Find Full Text PDFNa,K-ATPase with Disrupted Na Binding Sites I and III Binds Na with Increased Affinity at Site II and Undergoes Na-Activated Phosphorylation with ATP.
Biomolecules
January 2024
Department of Biomedicine, Aarhus University, DK-8000 Aarhus, Denmark.
Na,K-ATPase actively extrudes three cytoplasmic Na ions in exchange for two extracellular K ions for each ATP hydrolyzed. The atomic structure with bound Na identifies three Na sites, named I, II, and III. It has been proposed that site III is the first to be occupied and site II last, when Na binds from the cytoplasmic side.
View Article and Find Full Text PDFThe effect of metal ions on the Spf1p P5A-ATPase. High sensitivity to irreversible inhibition by zinc.
Arch Biochem Biophys
December 2022
Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Biológica, Consejo Nacional de Investigaciones Científicas y Técnicas CONICET-Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas IQUIFIB, Buenos Aires, Argentina. Electronic address:
The Spf1p protein from Saccharomyces cerevisiae belongs to the family of P5A-ATPases that have recently been shown to protect the endoplasmic reticulum by dislocating misinserted membrane proteins. The loss of function of P5A-ATPases leads to endoplasmic reticulum stress with a pleiotropic phenotype including protein, sterol and metal ion dyshomeostasis. Like other P-ATPases, Spf1p requires Mg.
View Article and Find Full Text PDFThe Na,K-ATPase in complex with beryllium fluoride mimics an ATPase phosphorylated state.
J Biol Chem
September 2022
Department of Molecular Biology and Genetics, DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus C, Denmark. Electronic address:
The Na,K-ATPase generates electrochemical gradients of Na and K across the plasma membrane via a functional cycle that includes various phosphoenzyme intermediates. However, the structure and function of these intermediates and how metal fluorides mimick them require further investigation. Here, we describe a 4.
View Article and Find Full Text PDFElectrostatic interactions between single arginine and phospholipids modulate physiological properties of sarcoplasmic reticulum Ca-ATPase.
Sci Rep
July 2022
Department of Biochemistry, Asahikawa Medical University, Midorigaoka-higashi 2-1-1-1, Asahikawa, 078-8510, Japan.
Arg324 of sarcoplasmic reticulum Ca-ATPase forms electrostatic interactions with the phosphate moiety of phospholipids in most reaction states, and a hydrogen bond with Tyr122 in other states. Using site-directed mutagenesis, we explored the functional roles of Arg324 interactions, especially those with lipids, which at first glance might seem too weak to modulate the function of such a large membrane protein. The hydrogen bond forms transiently and facilitates Ca binding from the cytoplasmic side.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!
© LitMetric 2025. All rights reserved.