Mercury blocks Na-K-ATPase by a ligand-dependent and reversible mechanism

1992 ◽  
Vol 262 (5) ◽  
pp. F830-F836 ◽  
Author(s):  
B. M. Anner ◽  
M. Moosmayer ◽  
E. Imesch
Keyword(s):  
Metal Binding ◽  
Inhibitory Concentration ◽  
Potent Inhibitor ◽  
Inhibitory Receptor ◽  
Protein Inhibitor ◽  
Binding Interface ◽  
Cellular Expression ◽  
Metal Binding Domain ◽  
Cardioactive Steroids ◽  
Atpase Inhibition

An inhibitory receptor for cardioactive steroids such as digoxin and ouabain is located at the extracellular surface of the Na-K-adenosinetriphosphatase (ATPase) molecule. Besides cardioactive steroids, mercury is a potent inhibitor of the Na-K-ATPase activity. The half-maximal inhibitory concentration (IC50), determined within 30 min at 37 degrees C at 1 microgram protein/ml, was 200 nM, despite the presence of 1 mM EDTA; the IC50 decreased with increasing protein/inhibitor ratio, and it reached 2.7 microM at 0.1 mg protein/ml and 20 microM at 1 mg protein/ml. The IC50 for Na-K-ATPase inhibition by the diuretic compound mersalyl was 4 and 5 microM for the nondiuretic p-chloromercuribenzenesulfonic acid at 0.1 mg protein/ml. The IC50 for HgCl2 inhibition was modulated by the presence of EDTA as well as by the pump ligands Mg, Na, K, and ATP. The E2 conformation of the Na-K-ATPase molecule was more sensitive to HgCl2 than the E1 conformation. The mercury antidote 2,3-dimercapto-1-propanesulfonic acid was able to reactivate approximately 70% of the blocked enzyme. In conclusion, a metal-binding domain of the Na-K-ATPase molecule with particular high affinity for Hg(II) was described functionally in the present work. Therefore Na-K-ATPase belongs to the metal-binding proteins. Metals may modulate the cellular expression and activity of the system by interacting with its metal-binding interface.

scholarly journals Manipulating the Conformation of 3,2′:6′,3″-Terpyridine in [Cu2(μ-OAc)4(3,2′:6′,3″-tpy)]n 1D-Polymers

Chemistry ◽  
2021 ◽  
Vol 3 (1) ◽  
pp. 182-198
Author(s):  
Dalila Rocco ◽  
Samantha Novak ◽  
Alessandro Prescimone ◽  
Edwin C. Constable ◽  
Catherine E. Housecroft
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Metal Binding ◽  
Polymer Chains ◽  
X Ray Diffraction ◽  
Face To Face ◽  
Single Crystal Structures ◽  
Π Stacking ◽  
Metal Binding Domain ◽  
Packing Interactions

We report the preparation and characterization of 4′-([1,1′-biphenyl]-4-yl)-3,2′:6′,3″-terpyridine (1), 4′-(4′-fluoro-[1,1′-biphenyl]-4-yl)-3,2′:6′,3″-terpyridine (2), 4′-(4′-chloro-[1,1′-biphenyl]-4-yl)-3,2′:6′,3″-terpyridine (3), 4′-(4′-bromo-[1,1′-biphenyl]-4-yl)-3,2′:6′,3″-terpyridine (4), and 4′-(4′-methyl-[1,1′-biphenyl]-4-yl)-3,2′:6′,3″-terpyridine (5), and their reactions with copper(II) acetate. Single-crystal structures of the [Cu2(μ-OAc)4L]n 1D-coordination polymers with L = 1–5 have been determined, and powder X-ray diffraction confirms that the single crystal structures are representative of the bulk samples. [Cu2(μ-OAc)4(1)]n and [Cu2(μ-OAc)4(2)]n are isostructural, and zigzag polymer chains are present which engage in π-stacking interactions between [1,1′-biphenyl]pyridine units. 1D-chains nest into one another to give 2D-sheets; replacing the peripheral H in 1 by an F substituent in 2 has no effect on the solid-state structure, indicating that bifurcated contacts (H...H for 1 or H...F for 2) are only secondary packing interactions. Upon going from [Cu2(μ-OAc)4(1)]n and [Cu2(μ-OAc)4(2)]n to [Cu2(μ-OAc)4(3)]n, [Cu2(μ-OAc)4(4)]n, and [Cu2(μ-OAc)4(5)]n·nMeOH, the increased steric demands of the Cl, Br, or Me substituent induces a switch in the conformation of the 3,2′:6′,3″-tpy metal-binding domain, and a concomitant change in dominant packing interactions to py–py and py–biphenyl face-to-face π-stacking. The study underlines how the 3,2′:6′,3″-tpy domain can adapt to different steric demands of substituents through its conformational flexibility.

Copper and Zinc Promote Interactions between Membrane-Anchored Peptides of the Metal Binding Domain of the Prion Protein†

Biochemistry ◽  
2007 ◽  
Vol 46 (14) ◽  
pp. 4261-4271 ◽  
Author(s):  
Angela G. Kenward ◽  
Libero J. Bartolotti ◽  
Colin S. Burns
Keyword(s):  
Prion Protein ◽  
Metal Binding ◽  
Binding Domain ◽  
Copper And Zinc ◽  
Metal Binding Domain

Copper chaperone Atox1 interacts with the metal-binding domain of Wilson's disease protein in cisplatin detoxification

2013 ◽  
Vol 454 (1) ◽  
pp. 147-156 ◽  
Author(s):  
Nataliya V. Dolgova ◽  
Sergiy Nokhrin ◽  
Corey H. Yu ◽  
Graham N. George ◽  
Oleg Y. Dmitriev
Keyword(s):  
Metal Binding ◽  
Wilson’S Disease ◽  
Wilson's Disease ◽  
Binding Domain ◽  
Binding Motif ◽  
Copper Chaperone ◽  
Copper Binding ◽  
Copper Transporters ◽  
Metal Binding Domain ◽  
Disease Protein

Human copper transporters ATP7B (Wilson's disease protein) and ATP7A (Menkes' disease protein) have been implicated in tumour resistance to cisplatin, a widely used anticancer drug. Cisplatin binds to the copper-binding sites in the N-terminal domain of ATP7B, and this binding may be an essential step of cisplatin detoxification involving copper ATPases. In the present study, we demonstrate that cisplatin and a related platinum drug carboplatin produce the same adduct following reaction with MBD2 [metal-binding domain (repeat) 2], where platinum is bound to the side chains of the cysteine residues in the CxxC copper-binding motif. This suggests the same mechanism for detoxification of both drugs by ATP7B. Platinum can also be transferred to MBD2 from copper chaperone Atox1, which was shown previously to bind cisplatin. Binding of the free cisplatin and reaction with the cisplatin-loaded Atox1 produce the same protein-bound platinum intermediate. Transfer of platinum along the copper-transport pathways in the cell may serve as a mechanism of drug delivery to its target in the cell nucleus, and explain tumour-cell resistance to cisplatin associated with the overexpression of copper transporters ATP7B and ATP7A.

The βE-Domain of Wheat Ec-1 Metallothionein: A Metal-Binding Domain with a Distinctive Structure

2009 ◽  
Vol 387 (1) ◽  
pp. 207-218 ◽  
Author(s):  
Estevão A. Peroza ◽  
Roland Schmucki ◽  
Peter Güntert ◽  
Eva Freisinger ◽  
Oliver Zerbe
Keyword(s):  
Metal Binding ◽  
Binding Domain ◽  
Metal Binding Domain ◽  
Distinctive Structure

Structural and functional studies of SAV1707 from Staphylococcus aureus elucidate its distinct metal-dependent activity and a crucial residue for catalysis

2021 ◽  
Vol 77 (5) ◽  
pp. 587-598
Author(s):  
Dong-Gyun Kim ◽  
Kyu-Yeon Lee ◽  
Sang Jae Lee ◽  
Seung-Ho Cheon ◽  
Yuri Choi ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Metal Binding ◽  
Binding Mode ◽  
Structure And Function ◽  
Functional Study ◽  
Functional Studies ◽  
Dependent Endonuclease ◽  
Metal Selectivity ◽  
Metal Binding Domain ◽  
And Function

The metallo-β-lactamase fold is the most abundant metal-binding domain found in two major kingdoms: bacteria and archaea. Despite the rapid growth in genomic information, most of these enzymes, which may play critical roles in cellular metabolism, remain uncharacterized in terms of structure and function. In this study, X-ray crystal structures of SAV1707, a hypothetical metalloenzyme from Staphylococcus aureus, and its complex with cAMP are reported at high resolutions of 2.05 and 1.55 Å, respectively, with a detailed atomic description. Through a functional study, it was verified that SAV1707 has Ni2+-dependent phosphodiesterase activity and Mn2+-dependent endonuclease activity, revealing a different metal selectivity depending on the reaction. In addition, the crystal structure of cAMP-bound SAV1707 shows a unique snapshot of cAMP that reveals the binding mode of the intermediate, and a key residue Phe511 that forms π–π interactions with cAMP was verified as contributing to substrate recognition by functional studies of its mutant. Overall, these findings characterized the relationship between the structure and function of SAV1707 and may provide further understanding of metalloenzymes possessing the metallo-β-lactamase fold.

scholarly journals A possible regulatory role for the metal-binding domain of CadA, the Listeria monocytogenes Cd2+ -ATPase

FEBS Letters ◽  
2001 ◽  
Vol 506 (3) ◽  
pp. 249-252 ◽  
Author(s):  
Nathalie Bal ◽  
Elisabeth Mintz ◽  
Florent Guillain ◽  
Patrice Catty
Keyword(s):  
Listeria Monocytogenes ◽  
Metal Binding ◽  
Binding Domain ◽  
Regulatory Role ◽  
Metal Binding Domain

scholarly journals A Novel Regulatory Metal Binding Domain Is Present in the C Terminus of Arabidopsis Zn2+-ATPase HMA2

2006 ◽  
Vol 281 (45) ◽  
pp. 33881-33891 ◽  
Author(s):  
Elif Eren ◽  
David C. Kennedy ◽  
Michael J. Maroney ◽  
José M. Argüello
Keyword(s):  
Metal Binding ◽  
Binding Domain ◽  
C Terminus ◽  
Metal Binding Domain

Mercury inhibits Na-K-ATPase primarily at the cytoplasmic side

1992 ◽  
Vol 262 (5) ◽  
pp. F843-F848 ◽  
Author(s):  
B. M. Anner ◽  
M. Moosmayer
Keyword(s):  
Active Transport ◽  
Metal Binding ◽  
Binding Interface ◽  
Intracellular Proteins ◽  
Active Ion Transport ◽  
A Cell ◽  
Intracellular Domains ◽  
Inside Out ◽  
K Transport ◽  
Cytoplasmic Side

The investigation of active Na-K transport inhibition by mercury is difficult to perform in a cell because of the presence of numerous other membrane and intracellular proteins modifiable by mercury. Thus purified Na-K-adenosinetriphosphatase (ATPase) molecules performing active transport in an artificial membrane are required to demonstrate unequivocally the inhibition of active transport by mercury. We made use of a single population of Na-K-ATPase liposomes filled with ATP and Na to show mercury inhibition of active 86Rb transport mediated by both the inside-out and right-side-out pumps in the same liposome. The effect of HgCl2 on the Na-K-ATPase in cell-like and reversed orientation was measured in comparison with convallatoxin. A dilution series showed that 10 microM externally added HgCl2 inhibited the active 86Rb transport at the cytoplasmic side first; at 50 microM both pump populations were blocked, indicating either membrane permeation by HgCl2 and inhibition at the internal intracellular domains or onset of extracellular action at higher HgCl2 concentration. The results show that the metal-binding interface of Na-K-ATPase molecule is profoundly implicated in active ion transport and that the intracellular part of the Na-K-ATPase molecule presents the primary target for mercury action.

scholarly journals Iron is a ligand of SecA-like metal-binding domains in vivo

2020 ◽  
Vol 295 (21) ◽  
pp. 7516-7528
Author(s):  
Tamar Cranford-Smith ◽  
Mohammed Jamshad ◽  
Mark Jeeves ◽  
Rachael A. Chandler ◽  
Jack Yule ◽  
...  
Keyword(s):  
Sodium Azide ◽  
Metal Binding ◽  
Cytoplasmic Membrane ◽  
E Coli ◽  
Binding Domains ◽  
Equilibrium Binding ◽  
Plausible Model ◽  
Metal Binding Domain ◽  
Linker Domain

The ATPase SecA is an essential component of the bacterial Sec machinery, which transports proteins across the cytoplasmic membrane. Most SecA proteins contain a long C-terminal tail (CTT). In Escherichia coli, the CTT contains a structurally flexible linker domain and a small metal-binding domain (MBD). The MBD coordinates zinc via a conserved cysteine-containing motif and binds to SecB and ribosomes. In this study, we screened a high-density transposon library for mutants that affect the susceptibility of E. coli to sodium azide, which inhibits SecA-mediated translocation. Results from sequencing this library suggested that mutations removing the CTT make E. coli less susceptible to sodium azide at subinhibitory concentrations. Copurification experiments suggested that the MBD binds to iron and that azide disrupts iron binding. Azide also disrupted binding of SecA to membranes. Two other E. coli proteins that contain SecA-like MBDs, YecA and YchJ, also copurified with iron, and NMR spectroscopy experiments indicated that YecA binds iron via its MBD. Competition experiments and equilibrium binding measurements indicated that the SecA MBD binds preferentially to iron and that a conserved serine is required for this specificity. Finally, structural modeling suggested a plausible model for the octahedral coordination of iron. Taken together, our results suggest that SecA-like MBDs likely bind to iron in vivo.

scholarly journals An EPR Study on the Interaction between the Cu(I) Metal Binding Domains of ATP7B and the Atox1 Metallochaperone

2020 ◽  
Vol 21 (15) ◽  
pp. 5536
Author(s):  
Michael Zaccak ◽  
Zena Qasem ◽  
Lada Gevorkyan-Airapetov ◽  
Sharon Ruthstein
Keyword(s):  
Metal Binding ◽  
Continuous Wave ◽  
Regulation System ◽  
Membrane Domain ◽  
Paramagnetic Resonance ◽  
Copper Trafficking ◽  
Binding Domains ◽  
Metal Binding Domain ◽  
Pulsed Electron Paramagnetic Resonance ◽  
Electron Paramagnetic

Copper’s essentiality and toxicity mean it requires a sophisticated regulation system for its acquisition, cellular distribution and excretion, which until now has remained elusive. Herein, we applied continuous wave (CW) and pulsed electron paramagnetic resonance (EPR) spectroscopy in solution to resolve the copper trafficking mechanism in humans, by considering the route travelled by Cu(I) from the metallochaperone Atox1 to the metal binding domains of ATP7B. Our study revealed that Cu(I) is most likely mediated by the binding of the Atox1 monomer to metal binding domain 1 (MBD1) and MBD4 of ATP7B in the final part of its extraction pathway, while the other MBDs mediate this interaction and participate in copper transfer between the various MBDs to the ATP7B membrane domain. This research also proposes that MBD1-3 and MBD4-6 act as two independent units.

Sign in / Sign up

Export Citation Format

Share Document