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Mangini V, Grasso G, Belviso BD, Sciacca MFM, Lanza V, Caliandro R, Milardi D. Stretching the chains: the destabilizing impact of Cu 2+ and Zn 2+ ions on K48-linked diubiquitin. Dalton Trans 2023; 52:11835-11849. [PMID: 37581921 DOI: 10.1039/d3dt01815f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
Ubiquitin signalling and metal homeostasis play key roles in controlling several physiological cellular activities, including protein trafficking and degradation. While some relationships between these two biochemical pathways have started to surface, our knowledge of their interplay remains limited. Here, we employ a variety of techniques, such as circular dichroism, differential scanning calorimetry, pressure perturbation calorimetry, fluorescence emission, SDS-PAGE, and small-angle X-ray scattering (SAXS) to evaluate the impact of Cu2+ and Zn2+ ions on the structure and stability of K48 linked diubiquitin (K48-Ub2), a simple model for polyubiquitin chains. The SAXS analysis results show that the structure of the metal-free protein is similar to that observed when the protein is bound to the E2 conjugating enzyme, lending support to the idea that the structure of unanchored K48-linked ubiquitin chains is sufficient for identification by conjugating enzymes without the need for an induced fit mechanism. Our results indicate that K48-Ub2 can coordinate up to four metal ions with both copper and zinc ions inducing slight changes to the secondary structure of the protein. However, we noted significant distinctions in their impacts on protein stability and overall architecture. Specifically, Cu2+ ions resulted in a destabilization of the protein structure, which facilitated the formation of dimer aggregates. Next, we observed a shift in the conformational dynamics of K48-Ub2 toward less compact and more flexible states upon metal ion binding, with Zn2+ inducing a more significant effect than Cu2+ ions. Our structural modelling study demonstrates that both metal ions induced perturbations in the K48-Ub2 structure, leading to the separation of the two monomers thus inhibiting interactions with E2 enzymes. In conclusion, the findings from this study enhance our comprehension of the mechanisms underlying Ub chains recognition. Moreover, they strengthen the notion that drug discovery initiatives aimed at targeting metal-mediated disruptions in Ub signaling hold great potential for treating a wide range of diseases that stem from abnormal protein accumulation.
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Affiliation(s)
- Vincenzo Mangini
- Istituto di Cristallografia - CNR sede di Bari, Via G. Amendola 122/O, 70126 Bari, Italy.
| | - Giulia Grasso
- Istituto di Cristallografia - CNR sede secondaria di Catania, Via P. Gaifami 18, 95126 Catania, Italy.
| | - Benny Danilo Belviso
- Istituto di Cristallografia - CNR sede di Bari, Via G. Amendola 122/O, 70126 Bari, Italy.
| | - Michele F M Sciacca
- Istituto di Cristallografia - CNR sede secondaria di Catania, Via P. Gaifami 18, 95126 Catania, Italy.
| | - Valeria Lanza
- Istituto di Cristallografia - CNR sede secondaria di Catania, Via P. Gaifami 18, 95126 Catania, Italy.
| | - Rocco Caliandro
- Istituto di Cristallografia - CNR sede di Bari, Via G. Amendola 122/O, 70126 Bari, Italy.
| | - Danilo Milardi
- Istituto di Cristallografia - CNR sede secondaria di Catania, Via P. Gaifami 18, 95126 Catania, Italy.
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Sciacca MF, Naletova I, Giuffrida ML, Attanasio F. Semax, a Synthetic Regulatory Peptide, Affects Copper-Induced Abeta Aggregation and Amyloid Formation in Artificial Membrane Models. ACS Chem Neurosci 2022; 13:486-496. [PMID: 35080861 PMCID: PMC8855339 DOI: 10.1021/acschemneuro.1c00707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
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Alzheimer’s
disease, the most common form of dementia, is
characterized by the aggregation of amyloid beta protein (Aβ).
The aggregation and toxicity of Aβ are strongly modulated by
metal ions and phospholipidic membranes. In particular, Cu2+ ions play a pivotal role in modulating Aβ aggregation. Although
in the last decades several natural or synthetic compounds were evaluated
as candidate drugs, to date, no treatments are available for the pathology.
Multifunctional compounds able to both inhibit fibrillogenesis, and
in particular the formation of oligomeric species, and prevent the
formation of the Aβ:Cu2+ complex are of particular
interest. Here we tested the anti-aggregating properties of a heptapeptide,
Semax, an ACTH-like peptide, which is known to form a stable complex
with Cu2+ ions and has been proven to have neuroprotective
and nootropic effects. We demonstrated through a combination of spectrofluorometric,
calorimetric, and MTT assays that Semax not only is able to prevent
the formation of Aβ:Cu2+ complexes but also has anti-aggregating
and protective properties especially in the presence of Cu2+. The results suggest that Semax inhibits fiber formation by interfering
with the fibrillogenesis of Aβ:Cu2+ complexes.
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Affiliation(s)
- Michele F.M. Sciacca
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Irina Naletova
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Maria Laura Giuffrida
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
| | - Francesco Attanasio
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Via Paolo Gaifami, 18, Catania 95126, Italy
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3
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Quantitative prediction of electronic absorption spectra of copper(II)-bioligand systems: Validation and applications. J Inorg Biochem 2019; 204:110953. [PMID: 31816442 DOI: 10.1016/j.jinorgbio.2019.110953] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/21/2019] [Accepted: 11/25/2019] [Indexed: 02/06/2023]
Abstract
The visible region of the electronic absorption spectra of Cu(II) complexes was studied by time-dependent density functional theory (TD-DFT). The performance of twelve functionals in the prediction of absorption maxima (λmax) was tested on eleven compounds with different geometry, donors and charge. The ranking of the functionals for λmax was determined in terms of mean absolute percent deviation (MAPD) and standard deviation (SD) and it is as follows: BHandHLYP > M06 ≫ CAM-B3LYP ≫ MPW1PW91 ~ B1LYP ~ BLYP > HSE06 ~ B3LYP > B3P86 ~ ω-B97x-D ≫ TPSSh ≫ M06-2X (MAPD) and BHandHLYP > M06 ~ HSE06 > ω-B97x-D ~ CAM-B3LYP ~ MPW1PW91 > B1LYP ~ B3LYP > B3P86 > BLYP ≫ TPSSh ≫ M06-2X (SD). With BHandHLYP functional the MAPD is 3.1% and SD is 2.3%, while with M06 the MAPD is 3.7% and SD is 3.7%. The protocol validated in the first step of the study was applied to: i) calculate the number of transitions in the spectra and relate them to the geometry of Cu(II) species; ii) determine the coordination of axial water(s); iii) predict the electronic spectra of the systems where Cu(II) is bound to human serum albumin (HSA) and to the regions 94-97 and 108-112 of prion protein (PrP). The results indicate that the proposed computational protocol allows a successful prediction of the electronic spectra of Cu(II) species and to relate an experimental spectrum to a specific structure.
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4
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DFT Protocol for EPR Prediction of Paramagnetic Cu(II) Complexes and Application to Protein Binding Sites. MAGNETOCHEMISTRY 2018. [DOI: 10.3390/magnetochemistry4040055] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
With the aim to provide a general protocol to interpret electron paramagnetic resonance (EPR) spectra of paramagnetic copper(II) coordination compounds, density functional theory (DFT) calculations of spin Hamiltonian parameters g and A for fourteen Cu(II) complexes with different charges, donor sets, and geometry were carried out using ORCA software. The performance of eleven functionals was tested, and on the basis of the mean absolute percent deviation (MAPD) and standard deviation (SD), the ranking of the functionals for Az is: B3LYP > B3PW91 ~ B3P86 > PBE0 > CAM-B3LYP > TPSSh > BH and HLYP > B2PLYP > MPW1PW91 > ω-B97x-D >> M06; and for gz is: PBE0 > BH and HLYP > B2PLYP > ω-B97x-D > B3PW91~B3LYP~B3P86 > CAM-B3LYP > TPSSh~MPW1PW91 >> M06. With B3LYP the MAPD with respect to A z exp t l is 8.6% with a SD of 4.2%, while with PBE0 the MAPD with respect to g z exp t l is 2.9% with a SD of 1.1%. The results of the validation confirm the fundamental role of the second order spin-orbit contribution to Az. The computational procedure was applied to predict the values of gz and Az of the adducts formed by Cu(II) with albumin and two fragments of prion protein, 106–126 and 180–193.
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Florenzano F, Veronica C, Ciasca G, Ciotti MT, Pittaluga A, Olivero G, Feligioni M, Iannuzzi F, Latina V, Maria Sciacca MF, Sinopoli A, Milardi D, Pappalardo G, Marco DS, Papi M, Atlante A, Bobba A, Borreca A, Calissano P, Amadoro G. Extracellular truncated tau causes early presynaptic dysfunction associated with Alzheimer's disease and other tauopathies. Oncotarget 2017; 8:64745-64778. [PMID: 29029390 PMCID: PMC5630290 DOI: 10.18632/oncotarget.17371] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 04/11/2017] [Indexed: 12/14/2022] Open
Abstract
The largest part of tau secreted from AD nerve terminals and released in cerebral spinal fluid (CSF) is C-terminally truncated, soluble and unaggregated supporting potential extracellular role(s) of NH2 -derived fragments of protein on synaptic dysfunction underlying neurodegenerative tauopathies, including Alzheimer's disease (AD). Here we show that sub-toxic doses of extracellular-applied human NH2 tau 26-44 (aka NH 2 htau) -which is the minimal active moiety of neurotoxic 20-22kDa peptide accumulating in vivo at AD synapses and secreted into parenchyma- acutely provokes presynaptic deficit in K+ -evoked glutamate release on hippocampal synaptosomes along with alteration in local Ca2+ dynamics. Neuritic dystrophy, microtubules breakdown, deregulation in presynaptic proteins and loss of mitochondria located at nerve endings are detected in hippocampal cultures only after prolonged exposure to NH 2 htau. The specificity of these biological effects is supported by the lack of any significant change, either on neuronal activity or on cellular integrity, shown by administration of its reverse sequence counterpart which behaves as an inactive control, likely due to a poor conformational flexibility which makes it unable to dynamically perturb biomembrane-like environments. Our results demonstrate that one of the AD-relevant, soluble and secreted N-terminally truncated tau forms can early contribute to pathology outside of neurons causing alterations in synaptic activity at presynaptic level, independently of overt neurodegeneration.
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Affiliation(s)
| | | | - Gabriele Ciasca
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Maria Teresa Ciotti
- Institute of Cellular Biology and Neuroscience, CNR, IRCSS Santa Lucia Foundation, Rome, Italy
| | - Anna Pittaluga
- Department of Pharmacy, Pharmacology and Toxicology Section, University of Genoa, Genoa, Viale Cembrano, Italy
| | - Gunedalina Olivero
- Department of Pharmacy, Pharmacology and Toxicology Section, University of Genoa, Genoa, Viale Cembrano, Italy
| | - Marco Feligioni
- European Brain Research Institute, Rome, Italy
- Department of Neurorehabilitation Sciences, Casa Cura Policlinico, Milan, Italy
| | | | | | | | | | - Danilo Milardi
- Institute of Biostructures and Bioimaging, CNR, Catania, Italy
| | | | - De Spirito Marco
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Massimiliano Papi
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Anna Atlante
- Institute of Biomembranes and Bioenergetics, CNR, Bari, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Viale Benedetto XV, Italy
| | - Antonella Bobba
- Institute of Biomembranes and Bioenergetics, CNR, Bari, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Viale Benedetto XV, Italy
| | - Antonella Borreca
- Institute of Cellular Biology and Neuroscience, CNR, IRCSS Santa Lucia Foundation, Rome, Italy
| | | | - Giuseppina Amadoro
- European Brain Research Institute, Rome, Italy
- Institute of Translational Pharmacology, CNR, Rome, Italy
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Sóvágó I, Várnagy K, Lihi N, Grenács Á. Coordinating properties of peptides containing histidyl residues. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.04.015] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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7
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Di Natale G, Turi I, Pappalardo G, Sóvágó I, Rizzarelli E. Cross-Talk Between the Octarepeat Domain and the Fifth Binding Site of Prion Protein Driven by the Interaction of Copper(II) with the N-terminus. Chemistry 2015; 21:4071-84. [DOI: 10.1002/chem.201405502] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Indexed: 12/21/2022]
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8
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Turi I, Sanna D, Garribba E, Pappalardo G, Sóvágó I. The effect of non-coordinating side chains on the metal binding affinities of peptides of histidine. Polyhedron 2013. [DOI: 10.1016/j.poly.2013.06.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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9
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Cations as switches of amyloid-mediated membrane disruption mechanisms: calcium and IAPP. Biophys J 2013; 104:173-84. [PMID: 23332070 DOI: 10.1016/j.bpj.2012.11.3811] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 11/09/2012] [Accepted: 11/21/2012] [Indexed: 12/15/2022] Open
Abstract
Disruption of the integrity of the plasma membrane by amyloidogenic proteins is linked to the pathogenesis of a number of common age-related diseases. Although accumulating evidence suggests that adverse environmental stressors such as unbalanced levels of metal ions may trigger amyloid-mediated membrane damage, many features of the molecular mechanisms underlying these events are unknown. Using human islet amyloid polypeptide (hIAPP, aka amylin), an amyloidogenic peptide associated with β-cell death in type 2 diabetes, we demonstrate that the presence of Ca(2+) ions inhibits membrane damage occurring immediately after the interaction of freshly dissolved hIAPP with the membrane, but significantly enhances fiber-dependent membrane disruption. In particular, dye leakage, quartz crystal microbalance, atomic force microscopy, and NMR experiments show that Ca(2+) ions promote a shallow membrane insertion of hIAPP, which leads to the removal of lipids from the bilayer through a detergent-like mechanism triggered by fiber growth. Because both types of membrane-damage mechanisms are common to amyloid toxicity by most amyloidogenic proteins, it is likely that unregulated ion homeostasis, amyloid aggregation, and membrane disruption are all parts of a self-perpetuating cycle that fuels amyloid cytotoxicity.
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10
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Arena G, La Mendola D, Pappalardo G, Sóvágó I, Rizzarelli E. Interactions of Cu2+ with prion family peptide fragments: Considerations on affinity, speciation and coordination. Coord Chem Rev 2012. [DOI: 10.1016/j.ccr.2012.03.038] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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Jószai V, Turi I, Kállay C, Pappalardo G, Di Natale G, Rizzarelli E, Sóvágó I. Mixed metal copper(II)-nickel(II) and copper(II)-zinc(II) complexes of multihistidine peptide fragments of human prion protein. J Inorg Biochem 2012; 112:17-24. [DOI: 10.1016/j.jinorgbio.2012.02.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 12/16/2011] [Accepted: 02/20/2012] [Indexed: 12/23/2022]
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12
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Interactions of two O-phosphorylresveratrol derivatives with model membranes. Arch Biochem Biophys 2012; 521:111-6. [DOI: 10.1016/j.abb.2012.03.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 03/16/2012] [Accepted: 03/17/2012] [Indexed: 12/19/2022]
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13
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Hirata A, Yajima S, Yasuhara T, Nokihara K. Structural Conversion Rate Changes of Recombinant Bovine Prion by Designed Synthetic Peptides. Int J Pept Res Ther 2012. [DOI: 10.1007/s10989-012-9294-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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14
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The effect of point mutations on copper(II) complexes with peptide fragments encompassing the 106–114 region of human prion protein. MONATSHEFTE FUR CHEMIE 2010. [DOI: 10.1007/s00706-010-0413-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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15
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La Mendola D, Magrì A, Campagna T, Campitiello MA, Raiola L, Isernia C, Hansson O, Bonomo RP, Rizzarelli E. A doppel alpha-helix peptide fragment mimics the copper(II) interactions with the whole protein. Chemistry 2010; 16:6212-23. [PMID: 20411530 DOI: 10.1002/chem.200902405] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The doppel protein (Dpl) is the first homologue of the prion protein (PrP(C)) to be discovered; it is overexpressed in transgenic mice that lack the prion gene, resulting in neurotoxicity. The whole prion protein is able to inhibit Dpl neurotoxicity, and its N-terminal domain is the determinant part of the protein function. This region represents the main copper(II) binding site of PrP(C). Dpl is able to bind at least one copper ion, and the specific metal-binding site has been identified as the histidine residue at the beginning of the third helical region. However, a reliable characterization of copper(II) coordination features has not been reported. In a previous paper, we studied the copper(II) interaction with a peptide that encompasses only the loop region potentially involved in metal binding. Nevertheless, we did not find a complete match between the EPR spectroscopic parameters of the copper(II) complexes formed with the synthesized peptide and those reported for the copper(II) binding sites of the whole protein. Herein, the synthesis of the human Dpl peptide fragment hDpl(122-139) (Ac-KPDNKLHQQVLWRLVQEL-NH(2)) and its copper(II) complex species are reported. This peptide encompasses the third alpha helix and part of the loop linking the second and the third helix of human doppel protein. The single-point-mutated peptide, hDpl(122-139)D124N, in which aspartate 124 replaces an asparagine residue, was also synthesized. This peptide was used to highlight the role of the carboxylate group on both the conformation preference of the Dpl fragment and its copper(II) coordination features. NMR spectroscopic measurements show that the hDpl(122-139) peptide fragment is in the prevailing alpha-helix conformation. It is localized within the 127-137 amino acid residue region that represents a reliable conformational mimic of the related protein domain. A comparison with the single-point-mutated hDpl(122-139)D124N reveals the significant role played by the aspartic residue in addressing the peptide conformation towards a helical structure. It is further confirmed by CD measurements. Potentiometric titrations were carried out in aqueous solutions to obtain the stability constant values of the species formed by copper(II) with the hDpl peptides. Spectroscopic studies (EPR, NMR, CD, UV/Vis) were performed to characterize the coordination environments of the different metal complexes. The EPR parameters of the copper(II) complexes with hDpl(122-139) match those of the previously reported copper(II) binding sites of the whole hDpl. Addition of the copper(II) ion to the peptide fragment does not alter the helical conformation of hDpl(122-139), as shown by CD spectra in the far-UV region. The aspartate-driven preorganized secondary structure is not significantly modified by the involvement of Asp124 in the copper(II) complex species that form in the physiological pH range. To elaborate on the potential role of copper(II) in the recently reported interaction between the PrP(C) and Dpl, the affinity of the copper(II) complexes towards the prion N terminus domain and the binding site of Dpl was reported.
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Affiliation(s)
- Diego La Mendola
- Istituto di Biostrutture e Bioimmagini-CNR, c/o Dipartimento di Scienze Chimiche, Viale A. Doria 6, 95125 Catania, Italy
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16
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The role of aromatic side-chains in amyloid growth and membrane interaction of the islet amyloid polypeptide fragment LANFLVH. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2010; 40:1-12. [DOI: 10.1007/s00249-010-0623-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 07/27/2010] [Accepted: 08/06/2010] [Indexed: 10/19/2022]
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17
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Turi I, Kállay C, Szikszai D, Pappalardo G, Di Natale G, De Bona P, Rizzarelli E, Sóvágó I. Nickel(II) complexes of the multihistidine peptide fragments of human prion protein. J Inorg Biochem 2010; 104:885-91. [DOI: 10.1016/j.jinorgbio.2010.04.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Revised: 04/16/2010] [Accepted: 04/20/2010] [Indexed: 10/19/2022]
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18
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Watanabe Y, Hiraoka W, Igarashi M, Ito K, Shimoyama Y, Horiuchi M, Yamamori T, Yasui H, Kuwabara M, Inagaki F, Inanami O. A novel copper(II) coordination at His186 in full-length murine prion protein. Biochem Biophys Res Commun 2010; 394:522-8. [DOI: 10.1016/j.bbrc.2010.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Accepted: 03/02/2010] [Indexed: 10/19/2022]
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19
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Kowalik-Jankowska T, Jankowska E, Kasprzykowski F. Coordination Abilities of a Fragment Containing D1 and H12 Residues of Neuropeptide γ and Products of Metal-Catalyzed Oxidation. Inorg Chem 2010; 49:2182-92. [DOI: 10.1021/ic902021j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
| | - Elżbieta Jankowska
- Faculty of Chemistry, University of Gdańsk, Sobieskiego 18, 80-952 Gdańsk, Poland
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Sciacca MFM, Pappalardo M, Attanasio F, Milardi D, La Rosa C, Grasso DM. Are fibrilgrowth and membrane damage linked processes? An experimental and computational study of IAPP12–18and IAPP21–27peptides. NEW J CHEM 2010. [DOI: 10.1039/b9nj00253g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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21
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Di Natale G, Ösz K, Nagy Z, Sanna D, Micera G, Pappalardo G, Sóvágó I, Rizzarell E. Interaction of Copper(II) with the Prion Peptide Fragment HuPrP(76−114) Encompassing Four Histidyl Residues within and outside the Octarepeat Domain. Inorg Chem 2009; 48:4239-50. [DOI: 10.1021/ic802190v] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Giuseppe Di Natale
- Department of Chemical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, Institute of Chemistry, University of Debrecen, H-4010 Debrecen, Hungary, Institute of Biomolecular Chemistry, CNR, Traversa La Crucca 3, 07040 Baldinca-Li Punti (Sassari), Italy, Department of Chemistry, University of Sassari, Via Vienna 2, 07100 Sassari, Italy, and Institute of Biostructures and Bioimaging, CNR, Vle A. Doria 6, 95125 Catania, Italy
| | - Katalin Ösz
- Department of Chemical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, Institute of Chemistry, University of Debrecen, H-4010 Debrecen, Hungary, Institute of Biomolecular Chemistry, CNR, Traversa La Crucca 3, 07040 Baldinca-Li Punti (Sassari), Italy, Department of Chemistry, University of Sassari, Via Vienna 2, 07100 Sassari, Italy, and Institute of Biostructures and Bioimaging, CNR, Vle A. Doria 6, 95125 Catania, Italy
| | - Zoltán Nagy
- Department of Chemical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, Institute of Chemistry, University of Debrecen, H-4010 Debrecen, Hungary, Institute of Biomolecular Chemistry, CNR, Traversa La Crucca 3, 07040 Baldinca-Li Punti (Sassari), Italy, Department of Chemistry, University of Sassari, Via Vienna 2, 07100 Sassari, Italy, and Institute of Biostructures and Bioimaging, CNR, Vle A. Doria 6, 95125 Catania, Italy
| | - Daniele Sanna
- Department of Chemical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, Institute of Chemistry, University of Debrecen, H-4010 Debrecen, Hungary, Institute of Biomolecular Chemistry, CNR, Traversa La Crucca 3, 07040 Baldinca-Li Punti (Sassari), Italy, Department of Chemistry, University of Sassari, Via Vienna 2, 07100 Sassari, Italy, and Institute of Biostructures and Bioimaging, CNR, Vle A. Doria 6, 95125 Catania, Italy
| | - Giovanni Micera
- Department of Chemical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, Institute of Chemistry, University of Debrecen, H-4010 Debrecen, Hungary, Institute of Biomolecular Chemistry, CNR, Traversa La Crucca 3, 07040 Baldinca-Li Punti (Sassari), Italy, Department of Chemistry, University of Sassari, Via Vienna 2, 07100 Sassari, Italy, and Institute of Biostructures and Bioimaging, CNR, Vle A. Doria 6, 95125 Catania, Italy
| | - Giuseppe Pappalardo
- Department of Chemical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, Institute of Chemistry, University of Debrecen, H-4010 Debrecen, Hungary, Institute of Biomolecular Chemistry, CNR, Traversa La Crucca 3, 07040 Baldinca-Li Punti (Sassari), Italy, Department of Chemistry, University of Sassari, Via Vienna 2, 07100 Sassari, Italy, and Institute of Biostructures and Bioimaging, CNR, Vle A. Doria 6, 95125 Catania, Italy
| | - Imre Sóvágó
- Department of Chemical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, Institute of Chemistry, University of Debrecen, H-4010 Debrecen, Hungary, Institute of Biomolecular Chemistry, CNR, Traversa La Crucca 3, 07040 Baldinca-Li Punti (Sassari), Italy, Department of Chemistry, University of Sassari, Via Vienna 2, 07100 Sassari, Italy, and Institute of Biostructures and Bioimaging, CNR, Vle A. Doria 6, 95125 Catania, Italy
| | - Enrico Rizzarell
- Department of Chemical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, Institute of Chemistry, University of Debrecen, H-4010 Debrecen, Hungary, Institute of Biomolecular Chemistry, CNR, Traversa La Crucca 3, 07040 Baldinca-Li Punti (Sassari), Italy, Department of Chemistry, University of Sassari, Via Vienna 2, 07100 Sassari, Italy, and Institute of Biostructures and Bioimaging, CNR, Vle A. Doria 6, 95125 Catania, Italy
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22
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Qi H, Yang L, Xue R, Song Y, Wang S, Li F. The third and fourth transmembrane domains of Slc11a1: Comparison of their structures and positioning in phospholipid model membranes. Biopolymers 2009; 92:52-64. [DOI: 10.1002/bip.21115] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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23
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Damante CA, Osz K, Nagy Z, Pappalardo G, Grasso G, Impellizzeri G, Rizzarelli E, Sóvágó I. The metal loading ability of beta-amyloid N-terminus: a combined potentiometric and spectroscopic study of copper(II) complexes with beta-amyloid(1-16), its short or mutated peptide fragments, and its polyethylene glycol (PEG)-ylated analogue. Inorg Chem 2008; 47:9669-83. [PMID: 18808108 DOI: 10.1021/ic8006052] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Alzheimer's disease (AD) is becoming a rapidly growing health problem, as it is one of the main causes of dementia in the elderly. Interestingly, copper(II) (together with zinc and iron) ions are accumulated in amyloid deposits, suggesting that metal binding to Abeta could be involved in AD pathogenesis. In Abeta, the metal binding is believed to occur within the N-terminal region encompassing the amino acid residues 1-16. In this work, potentiometric, spectroscopic (UV-vis, circular dichroism, and electron paramagnetic resonance), and electrospray ionization mass spectrometry (ESI-MS) approaches were used to investigate the copper(II) coordination features of a new polyethylene glycol (PEG)-conjugated Abeta peptide fragment encompassing the 1-16 amino acid residues of the N-terminal region (Abeta(1-16)PEG). The high water solubility of the resulting metal complexes allowed us to obtain a complete complex speciation at different metal-to-ligand ratios ranging from 1:1 to 4:1. Potentiometric and ESI-MS data indicate that Abeta(1-16)PEG is able to bind up to four copper(II) ions. Furthermore, in order to establish the coordination environment at each metal binding site, a series of shorter peptide fragments of Abeta, namely, Abeta(1-4), Abeta(1-6), AcAbeta(1-6), and AcAbeta(8-16)Y10A, were synthesized, each encompassing a potential copper(II) binding site. The complexation properties of these shorter peptides were also comparatively investigated by using the same experimental approach.
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Affiliation(s)
- Chiara A Damante
- Department of Chemical Sciences, University of Catania, V.le A. Doria 6, 95125 Catania, Italy
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24
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Rajković S, Kállay C, Serényi R, Malandrinos G, Hadjiliadis N, Sanna D, Sóvágó I. Complex formation processes of terminally protected peptides containing two or three histidyl residues. Characterization of the mixed metal complexes of peptides. Dalton Trans 2008:5059-71. [PMID: 18802621 DOI: 10.1039/b808323a] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Copper(II), nickel(II) and zinc(II) complexes of the peptides Ac-HVVH-NH2 and Ac-HAAHVVH-NH2 have been studied by potentiometric, UV-vis, CD, EPR and NMR spectroscopic measurements. Both tetra and heptapeptides can form relatively stable macrochelates with copper(II), nickel(II) and zinc(II) ions, in which the ligands are coordinated via the side-chain imidazole functions. Formation of the macrochelates slightly suppresses, but cannot prevent the copper(II) and nickel(II) ion promoted deprotonation and coordination of the amide functionalities. The overall stoichiometry of the major species is [MH(-3)L]- with a 4N (=N-,N-,N-,Nim) coordination mode. In the case of Ac-HAAHVVH-NH2, coordination isomers of this species can exist with a preference for copper(II) or nickel(II) binding at the internal histidyl residue. In the copper(II)-Ac-HAAHVVH-NH2 system, the presence of the two anchoring sites results in the formation of dinuclear complexes. The existence of these species requires the involvement of amide functions in metal binding. Both equilibrium and spectroscopic data support the fact that the copper(II) ions of the dinuclear species are independent from each other providing a good chance for the formation of various mixed metal complexes. It was found that zinc(II) is not able to significantly alter the copper(II) binding of the heptapeptide, but it can occupy the uncoordinated histidyl sites. The formation of the copper(II)-nickel(II) mixed species was obtained in alkaline solutions and CD spectra suggest the statistical distribution of the two metal ions among the histidyl residues. The binding of HAAHVVH to palladium(II) is exclusive below pH 8 and the mixed metal species of palladium(II) and copper(II) ions are formed only in slightly basic solutions.
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Affiliation(s)
- Snezana Rajković
- Department of Chemistry, Faculty of Science, University of Kragujevac, R. Domanovića 12, P.O. Box 60, 34000 Kragujevac, Serbia
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25
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Kowalik-Jankowska T, Biega Ł, Kuczer M, Konopińska D. Copper(II) complexes of Neobelliera Bullata Trypsin Modulating Oostatic Factor and its analogues. J Inorg Biochem 2008; 102:1615-22. [DOI: 10.1016/j.jinorgbio.2008.02.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 02/20/2008] [Accepted: 02/20/2008] [Indexed: 10/22/2022]
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26
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Drew SC, Barnham KJ. Biophysical investigations of the prion protein using electron paramagnetic resonance. Methods Mol Biol 2008; 459:173-196. [PMID: 18576156 DOI: 10.1007/978-1-59745-234-2_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The binding of paramagnetic metal ions is thought to be an essential function of the prion protein and lends itself to interrogation by electron paramagnetic resonance (EPR), which probes the local coordination environment of bound metal ions to provide details of the metal-binding affinity, stoichiometry, and the symmetry and identity of its ligating atoms. It is also capable of identifying reactive oxygen/nitrogen species and peptide-derived radicals, in addition to monitoring protein-membrane dynamics and conformation by using site-directed spin labeling. An overview of the EPR technique as applied to the prion protein is given, key results are summarized, and some future experimental avenues are outlined.
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Affiliation(s)
- Simon C Drew
- Department of Pathology and Mental Health Research Institute of Victoria, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, Australia
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27
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Guantieri V, Venzo A, Marco VD, Acampora M, Biondi B. Potentiometric and NMR studies on Cd2+ coordination with the histidine-containing Ac184–188NH2 prion protein fragment. Inorganica Chim Acta 2007. [DOI: 10.1016/j.ica.2007.05.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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28
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Osz K, Nagy Z, Pappalardo G, Di Natale G, Sanna D, Micera G, Rizzarelli E, Sóvágó I. Copper(II) Interaction with Prion Peptide Fragments Encompassing Histidine Residues Within and Outside the Octarepeat Domain: Speciation, Stability Constants and Binding Details. Chemistry 2007; 13:7129-43. [PMID: 17566127 DOI: 10.1002/chem.200601568] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A 31-mer polypeptide, which encompasses residues 84-114 of human prion protein HuPrP(84-114) and contains three histidyl residues, namely one from the octarepeat (His85) and two histidyl residues from outside the octarepeat region (His96 and His111), and its mutants with two histidyl residues HuPrP(84-114)His85Ala, HuPrP(84-114) His96Ala, HuPrP(84-114)His111Ala and HuPrP(91-115) have been synthesised and their Cu2+ complexes studied by potentiometric and spectroscopic (UV/Vis, CD, EPR, ESI-MS) techniques. The results revealed a high Cu2+-binding affinity of all peptides, and the spectroscopic studies made it possible to clarify the coordination mode of the peptides in the different complex species. The imidazole nitrogen donor atoms of histidyl residues are the exclusive metal-binding sites below pH 5.5, and they have a preference for macrochelate structure formation. The deprotonation and metal-ion coordination of amide functions take place by increasing the pH; all of the histidines can be considered to be independent metal-binding sites in these species. As a consequence, di- and trinuclear complexes can be present even in equimolar samples of the metal ion and peptides, but the ratios of polynuclear species do not exceed the statistically expected ones; this excludes the possibility of cooperative Cu2+ binding. The species with a (N(im),N,N)-binding mode are favoured around pH 7, and their stability is enhanced by the macrochelation from another histidyl residue in the mononuclear complexes. The independence of the histidyl sites results in the existence of coordination isomers and the preference for metal binding follows the order of: His111>His96>His85. Deprotonation and metal-ion coordination of the third amide functions were detected in slightly alkaline solutions at each of the metal-binding sites; all had a (N(im),N,N,N)-coordination mode. Spectroscopic measurements also made it clear that the four lysyl amino groups of the peptides are not metal-binding sites in any cases.
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Affiliation(s)
- Katalin Osz
- Department of Inorganic and Analytical Chemistry, University of Debrecen, 4010 Debrecen, Hungary
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29
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Kállay C, Várnagy K, Malandrinos G, Hadjiliadis N, Sanna D, Sóvágó I. Copper(II) complexes of terminally protected pentapeptides containing three histidyl residues in alternating positions, Ac-His-Xaa-His-Yaa-His-NH2. Dalton Trans 2006:4545-52. [PMID: 17016565 DOI: 10.1039/b608190h] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Copper(II) complexes of the pentapeptides Ac-HisAlaHisValHis-NH2, Ac-HisValHisAlaHis-NH2, Ac-HisProHisAlaHis-NH2, Ac-HisAlaHisProHis-NH2, Ac-HisGlyHisValHis-NH2 and Ac-HisValHisGlyHis-NH2 have been studied by potentiometric, UV-Vis, CD and EPR spectroscopic methods. It has been found that the pentapeptides are efficient ligands for the complexation with copper(II) and exhibit an outstanding versatility in the co-ordination geometry of complexes. The presence of three histidyl residues provides a high possibility for the formation of macrochelates via the exclusive binding of imidazole-N donor atoms. The macrochelation suppresses, but cannot preclude the deprotonation and metal ion co-ordination of amide functions and the species [CuH(-2)L] and [Cu2H(-4)L] predominate at physiological pH in equimolar solutions and in the presence of excess metal ions, respectively. It is also clear from the data that both C-terminal and internal histidyl residues can work as the anchoring sites for metal binding and subsequent amide deprotonation resulting in the formation of co-ordination isomers and dinuclear species in equimolar solutions and in the presence of excess metal ions, respectively. In more alkaline solutions (pH approximately 10) a third amide function can be deprotonated and co-ordinated in the species [CuH(-3)L]- with (N-,N-,N-,N(im)) co-ordination. The dinuclear species [Cu2H(-5)L]- and [Cu2H(-6)L](2-) containing hydroxide ions and/or imidazolato bridges are formed at high pH in the presence of excess of metal ions. The insertion of one proline into the sequence preceding histidyl residues hinders the deprotonation of amide functions at that site and the formation of only mononuclear complexes was observed with these peptides.
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Affiliation(s)
- Csilla Kállay
- Department of Inorganic and Analytical Chemistry, University of Debrecen, H-4010, Debrecen, Hungary
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30
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Jószai V, Nagy Z, Osz K, Sanna D, Di Natale G, La Mendola D, Pappalardo G, Rizzarelli E, Sóvágó I. Transition metal complexes of terminally protected peptides containing histidyl residues. J Inorg Biochem 2006; 100:1399-409. [PMID: 16730799 DOI: 10.1016/j.jinorgbio.2006.04.003] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Revised: 04/10/2006] [Accepted: 04/14/2006] [Indexed: 11/26/2022]
Abstract
Histidine-containing peptide fragments of prion protein are efficient ligands to bind various transition metal ions and they have high selectivity in metal binding. The metal ion affinity follows the order: Pd(II)>>Cu(II)>>Ni(II)Zn(II)>Cd(II) approximately Co(II)>Mn(II). The high selectivity of metal binding is connected to the involvement of both imidazole and amide nitrogen atoms in metal binding for Pd(II), Cu(II) and Ni(II), while only the monodentate N(im)-coordination is possible with the other metal ions. The stoichiometry and binding mode of palladium(II) complexes show great variety depending on the metal ion to ligand ratio, pH and especially the presence of coordinating donor atoms in the side chains of peptide fragments. It is also clear from our data that the peptide fragments containing histidine outside the octarepeat (His96, His111 and His187) are more efficient ligands than the monomer peptide fragments of the octarepeat domain.
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Affiliation(s)
- Viktória Jószai
- Department of Inorganic and Analytical Chemistry, University of Debrecen, P.O. Box 21, H-4010 Debrecen, Hungary
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31
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Abstract
Metal binding affinity and selectivity of peptides are reviewed with a special emphasis on the high structural variety of peptide complexes. The most common structural type of these complexes is built up by the deprotonation and metal ion coordination of subsequent amide groups in the form of fused five-membered chelate rings. The metal ion selectivity of this process and the role of various anchoring groups are discussed in detail. The highest metal binding affinity of peptides is connected to the presence of two anchoring groups in appropriate location (the "double anchor"): e.g. the NH2-Xaa-Xaa-His/Cys/Asp/Met-Xaa sequence. Among the side chain donor functions, the imidazole of histidyl and thiolate of cysteinyl residues are the most effective ligating groups and their involvement in metal binding results in a great variety of different macrochelate or loop structures and/or formation of various polynuclear complexes. Examples of these structural motifs and their possible applications have been thoroughly discussed.
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Affiliation(s)
- Imre Sóvágó
- Department of Inorganic and Analytical Chemistry, University of Debrecen, H-4010, Debrecen, Hungary
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32
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Kowalik-Jankowska T, Rajewska A, Jankowska E, Grzonka Z. Copper(ii) binding by fragments of α-synuclein containing M1-D2- and -H50-residues; a combined potentiometric and spectroscopic study. Dalton Trans 2006:5068-76. [PMID: 17060993 DOI: 10.1039/b610619f] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Stability constants and ligand donor sets of the copper(II) complexes of the NH2-29-56(L1)(AA30GKTKEGVLYV40GSKTKEGVVH50GVATVA56-NH2), NH2-M29-D30-56(L2) and Ac-M29-D30-56(L3) fragments of alpha-synuclein were determined in aqueous solution for 1 : 1 metal-to-ligand molar ratio in the pH range 2.5-10.5. The tyrosine residue in the 39th position of the alpha-synuclein fragments does not take part in the coordination of the metal ion. The potentiometric and spectroscopic data (UV-Vis, CD, EPR) show that acetylation of the amino terminal group induces significant changes in the coordination properties of the L3 fragment compared to that of the L2 peptide. When the amino group is blocked (L3) the imidazole nitrogen of the histidine residue acts as an anchoring site and at higher pH the 3N {N(Im),2N-} and 4N {N(Im),3N-} complexes are formed. The L1 peptide at physiological pH forms in equilibrium 3N {NH2,N-,CO,N(Im)} and 4N {NH2,2N-,N(Im)} complexes. For the L2 peptide the coordination of the copper(II) ions starts from the N-terminal Met residue and with increasing of pH the Asp residue in second position of amino acid sequence coordinates and stabilizes significantly the 2N complex as a result of chelation through the beta-carboxylate group. At physiological pH the 3N {NH2,N-,beta-COO-,N(Im)} coordination mode dominates. At pH above 6 the results for the L2 fragment suggest the formation of 3N and 4N complexes (in equatorial plane) and the involvement of the lateral NH2 group of Lys residue in the axial coordination of Cu(II) ion. In CD spectra sigma (epsilon-NH2-Lys) --> Cu(II) charge transfer transition is observed. The stability constants for the L2 fragment of alpha-synuclein of the 4N {NH2,2N-,N(Im)} and {NH2,3N-} complexes are higher about 1.5 and 0.7 orders of magnitude, respectively, by comparison to those of the L1 peptide. This increase may be explained by the involvement of the epsilon-NH2 group of Lys residue in the coordination sphere of metal ion.
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