C-Terminal Domain of the Membrane Copper Transporter Ctr1 fromSaccharomyces cerevisiaeBinds Four Cu(I) Ions as a Cuprous-Thiolate Polynuclear Cluster:  Sub-femtomolar Cu(I) Affinity of Three Proteins Involved in Copper Trafficking

2004 ◽  
Vol 126 (10) ◽  
pp. 3081-3090 ◽  
Author(s):  
Zhiguang Xiao ◽  
Fionna Loughlin ◽  
Graham N. George ◽  
Geoffrey J. Howlett ◽  
Anthony G. Wedd
Keyword(s):  
Copper Transporter ◽  
Copper Trafficking ◽  
Terminal Domain ◽  
Polynuclear Cluster

Understanding Copper Trafficking in Bacteria:  Interaction between the Copper Transport Protein CopZ and the N-Terminal Domain of the Copper ATPase CopA fromBacillus subtilis†

Biochemistry ◽  
2003 ◽  
Vol 42 (7) ◽  
pp. 1939-1949 ◽  
Author(s):  
Lucia Banci ◽  
Ivano Bertini ◽  
Simone Ciofi-Baffoni ◽  
Rebecca Del Conte ◽  
Leonardo Gonnelli
Keyword(s):  
Transport Protein ◽  
Copper Transport ◽  
Copper Trafficking ◽  
Terminal Domain

scholarly journals The Fe(II) permease Fet4p functions as a low affinity copper transporter and supports normal copper trafficking in Saccharomyces cerevisiae

2000 ◽  
Vol 351 (2) ◽  
pp. 477-484 ◽  
Author(s):  
Richard HASSETT ◽  
David R. DIX ◽  
David J. EIDE ◽  
Daniel J. KOSMAN
Keyword(s):  
Metal Ion ◽  
Competitive Inhibitor ◽  
Yeast Cells ◽  
Amino Acid Residues ◽  
Copper Uptake ◽  
Copper Transporter ◽  
Copper Trafficking ◽  
High Affinity ◽  
Uptake Pathway ◽  
Mutant Forms

The plasma-membrane of Saccharomycescerevisiae contains high affinity permeases for Cu(I) and Fe(II). A low affinity Fe(II) permease has also been identified, designated Fet4p. A corresponding low affinity copper permease has not been characterized, although yeast cells that lack high affinity copper uptake do accumulate this metal ion. We demonstrate in the present study that Fet4p can function as a low affinity copper permease. Copper is a non-competitive inhibitor of 55Fe uptake through Fet4p (Ki = 22µM). Fet4p-dependent 67Cu uptake was kinetically characterized, with Km and Vmax values of 35µM and 8pmol of copper/min per 106 cells respectively. A fet4-containing strain exhibited no saturable, low affinity copper uptake indicating that this uptake was attributable to Fet4p. Mutant forms of Fet4p that exhibited decreased efficiency in 55/59Fe uptake were similarly compromised in 67Cu uptake, indicating that similar amino acid residues in Fet4p contribute to both uptake processes. The copper taken into the cell by Fet4p was metabolized similarly to the copper taken into the cell by the high affinity permease, Ctr1p. This was shown by the Fet4p-dependence of copper activation of Fet3p, the copper oxidase that supports high affinity iron uptake in yeast. Also, copper-transported by Fet4p down-regulated the copper sensitive transcription factor, Mac1p. Whether supplied by Ctr1p or by Fet4p, an intracellular copper concentration of approx. 10µM caused a 50% reduction in the transcriptional activity of Mac1p. The data suggest that the initial trafficking of newly arrived copper in the yeast cell is independent of the copper uptake pathway involved, and that this copper may be targeted first to a presumably small ‘holding’pool prior to its partitioning within the cell.

scholarly journals Nerve Growth Factor Peptides Bind Copper(II) with High Affinity: A Thermodynamic Approach to Unveil Overlooked Neurotrophin Roles

2021 ◽  
Vol 22 (10) ◽  
pp. 5085
Author(s):  
Antonio Magrì ◽  
Diego La La Mendola ◽  
Enrico Rizzarelli
Keyword(s):  
Nerve Growth Factor ◽  
Growth Factor ◽  
Disease Onset ◽  
Synaptic Cleft ◽  
Peptide Fragments ◽  
Copper Transporter ◽  
Complex Species ◽  
Nerve Growth ◽  
Terminal Domain ◽  
The Stability

Nerve growth factor (NGF) is a protein essential to neurons survival, which interacts with its receptor as a non-covalent dimer. Peptides belonging to NGF N-terminal domain are able to mimic the activity of the whole protein. Such activity is affected by the presence of copper ions. The metal is released in the synaptic cleft where proteins, not yet identified, may bind and transfer to human copper transporter 1 (hCtr1), for copper uptake in neurons. The measurements of the stability constants of copper complexes formed by amyloid beta and hCtr1 peptide fragments suggest that beta-amyloid (Aβ) can perform this task. In this work, the stability constant values of copper complex species formed with the dimeric form of N-terminal domain, sequence 1–15 of the protein, were determined by means of potentiometric measurements. At physiological pH, NGF peptides bind one equivalent of copper ion with higher affinity of Aβ and lower than hCtr1 peptide fragments. Therefore, in the synaptic cleft, NGF may act as a potential copper chelating molecule, ionophore or chaperone for hCtr1 for metal uptake. Copper dyshomeostasis and mild acidic environment may modify the balance between metal, NGF, and Aβ, with consequences on the metal cellular uptake and therefore be among causes of the Alzheimer’s disease onset.

Structure of clathrin cages and coats in ice

1986 ◽  
Vol 44 ◽  
pp. 94-97
Author(s):  
G.P.A. Vigers ◽  
R.A. Crowther ◽  
B.M.F. Pearse
Keyword(s):  
Electron Microscopy ◽  
Heavy Chain ◽  
Outer Part ◽  
Coated Vesicles ◽  
Eukaryotic Cells ◽  
Coat Proteins ◽  
Terminal Domain ◽  
Clathrin Heavy Chain ◽  
Membrane Components

Clathrin forms the polyhedral cage of coated vesicles, which mediate the transfer of selected membrane components within eukaryotic cells. Clathrin cages and coated vesicles have been extensively studied by electron microscopy of negatively stained preparations and shadowed specimens. From these studies the gross morphology of the outer part of the polyhedral coat has been established and some features of the packing of clathrin trimers into the coat have also been described. However these previous studies have not revealed any internal details about the position of the terminal domain of the clathrin heavy chain, the location of the 100kd-50kd accessory coat proteins or the interactions of the coat with the enclosed membrane.

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