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Structure and Modification of Electrode Materials for Protein Electrochemistry. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 158:43-73. [PMID: 27506830 DOI: 10.1007/10_2015_5011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The interactions between proteins and electrode surfaces are of fundamental importance in bioelectrochemistry, including photobioelectrochemistry. In order to optimise the interaction between electrode and redox protein, either the electrode or the protein can be engineered, with the former being the most adopted approach. This tutorial review provides a basic description of the most commonly used electrode materials in bioelectrochemistry and discusses approaches to modify these surfaces. Carbon, gold and transparent electrodes (e.g. indium tin oxide) are covered, while approaches to form meso- and macroporous structured electrodes are also described. Electrode modifications include the chemical modification with (self-assembled) monolayers and the use of conducting polymers in which the protein is imbedded. The proteins themselves can either be in solution, electrostatically adsorbed on the surface or covalently bound to the electrode. Drawbacks and benefits of each material and its modifications are discussed. Where examples exist of applications in photobioelectrochemistry, these are highlighted.
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Direct electrochemistry of cytochrome c entrapped in agarose hydrogel in room temperature ionic liquids. Bioelectrochemistry 2011; 82:55-62. [DOI: 10.1016/j.bioelechem.2011.05.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Revised: 05/18/2011] [Accepted: 05/19/2011] [Indexed: 11/18/2022]
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3
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Guo Z, Zhang H, Gai P, Duan J. Direct electrochemistry of cytochrome c entrapped in agarose hydrogel by protein film voltammetry. RUSS J ELECTROCHEM+ 2011. [DOI: 10.1134/s1023193511020108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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ZHANG HN, GUO ZY, GAI PP. Research Progress in Protein Film Voltammetry. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2009. [DOI: 10.1016/s1872-2040(08)60093-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Antonkine ML, Maes EM, Czernuszewicz RS, Breitenstein C, Bill E, Falzone CJ, Balasubramanian R, Lubner C, Bryant DA, Golbeck JH. Chemical rescue of a site-modified ligand to a [4Fe–4S] cluster in PsaC, a bacterial-like dicluster ferredoxin bound to Photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:712-24. [PMID: 17434441 DOI: 10.1016/j.bbabio.2007.02.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2006] [Revised: 01/21/2007] [Accepted: 02/02/2007] [Indexed: 10/23/2022]
Abstract
Chemical rescue of site-modified amino acids using externally supplied organic molecules represents a powerful method to investigate structure-function relationships in proteins. Here we provide definitive evidence that aryl and alkyl thiolates, reagents typically used for in vitro iron-sulfur cluster reconstitutions, serve as rescue ligands to a site-specifically modified [4Fe-4S](1+,2+) cluster in PsaC, a bacterial dicluster ferredoxin-like subunit of Photosystem I. PsaC binds two low-potential [4Fe-4S](1+,2+) clusters termed F(A) and F(B). In the C13G/C33S variant of PsaC, glycine has replaced cysteine at position 13 creating a protein that is missing one of the ligating amino acids to iron-sulfur cluster F(B). Using a variety of analytical techniques, including non-heme iron and acid-labile sulfur assays, and EPR, resonance Raman, and Mössbauer spectroscopies, we showed that the C13G/C33S variant of PsaC binds two [4Fe-4S](1+,2+) clusters, despite the absence of one of the biological ligands. (19)F NMR spectroscopy indicated that the external thiolate replaces cysteine 13 as a substitute ligand to the F(B) cluster. The finding that site-modified [4Fe-4S](1+,2+) clusters can be chemically rescued with external thiolates opens new opportunities for modulating their properties in proteins. In particular, it provides a mechanism to attach an additional electron transfer cofactor to the protein via a bound, external ligand.
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Affiliation(s)
- Mikhail L Antonkine
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA.
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Hirst J. Elucidating the mechanisms of coupled electron transfer and catalytic reactions by protein film voltammetry. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2006; 1757:225-39. [PMID: 16730325 DOI: 10.1016/j.bbabio.2006.04.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 03/28/2006] [Accepted: 04/01/2006] [Indexed: 11/30/2022]
Abstract
Protein film voltammetry, the direct electrochemistry of redox enzymes and proteins, provides precise and comprehensive information on complicated reaction mechanisms. By controlling the driving force for a reaction (using the applied potential) and monitoring the reaction in real time (using the current), it allows thermodynamic and kinetic information to be determined simultaneously. Two challenges are inherent to protein film voltammetry: (i) to adsorb the protein or enzyme in a native and active configuration on the electrode surface, and (ii) to understand and interpret voltammetric results on both a qualitative and quantitative level, allowing mechanistic models to be proposed and rigorous experiments to test these models to be devised. This review focuses on the second of these two challenges. It describes how to use protein film voltammetry to derive mechanistic and biochemically relevant information about redox proteins and enzymes, and how to evaluate and interpret voltammetric results. Selected key studies are described in detail, to illustrate their underlying principles, strategies and physical interpretations.
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Affiliation(s)
- Judy Hirst
- Medical Research Council Dunn Human Nutrition Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge, CB2 2XY, UK.
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Acevedo O, Jorgensen WL. Influence of inter- and intramolecular hydrogen bonding on kemp decarboxylations from QM/MM simulations. J Am Chem Soc 2005; 127:8829-34. [PMID: 15954791 DOI: 10.1021/ja051793y] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Kemp decarboxylation reaction for benzisoxazole-3-carboxylic acid derivatives has been investigated using QM/MM calculations in protic and dipolar aprotic solvents. Aprotic solvents have been shown to accelerate the rates of reaction by 7-8 orders of magnitude over water; however, the inclusion of an internal hydrogen bond effectively inhibits the reaction with near solvent independence. The effects of solvation and intramolecular hydrogen bonding on the reactants, transition structures, and the rate of reaction are elucidated using two-dimensional potentials of mean force (PMF) derived from free energy perturbation calculations in Monte Carlo simulations (MC/FEP). Free energies of activation in six solvents have been computed to be in close agreement with experiment. Solute-solvent interaction energies show that poorer solvation of the reactant anion in the dipolar aprotic solvents is primarily responsible for the observed rate enhancements over protic media. In addition, a discrepancy for the experimental rate in chloroform has been studied in detail with the conclusion that ion-pairing between the reactant anion and tetramethylguanidinium counterion is responsible for the anomalously slow reaction rate. The overall quantitative success of the computations supports the present QM/MM/MC approach, which features PDDG/PM3 as the QM method.
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Affiliation(s)
- Orlando Acevedo
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107, USA
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Hänzelmann P, Schindelin H. Crystal structure of the S-adenosylmethionine-dependent enzyme MoaA and its implications for molybdenum cofactor deficiency in humans. Proc Natl Acad Sci U S A 2004; 101:12870-5. [PMID: 15317939 PMCID: PMC516487 DOI: 10.1073/pnas.0404624101] [Citation(s) in RCA: 193] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2004] [Indexed: 11/18/2022] Open
Abstract
The MoaA and MoaC proteins catalyze the first step during molybdenum cofactor biosynthesis, the conversion of a guanosine derivative to precursor Z. MoaA belongs to the S-adenosylmethionine (SAM)-dependent radical enzyme superfamily, members of which catalyze the formation of protein and/or substrate radicals by reductive cleavage of SAM by a [4Fe-4S] cluster. A defined in vitro system is described, which generates precursor Z and led to the identification of 5'-GTP as the substrate. The structures of MoaA in the apo-state (2.8 angstroms) and in complex with SAM (2.2 angstroms) provide valuable insights into its mechanism and help to define the defects caused by mutations in the human ortholog of MoaA that lead to molybdenum cofactor deficiency, a usually fatal disease accompanied by severe neurological symptoms. The central core of each subunit of the MoaA dimer is an incomplete triosephosphate isomerase barrel formed by the N-terminal part of the protein, which contains the [4Fe-4S] cluster typical for SAM-dependent radical enzymes. SAM is the fourth ligand to the cluster and binds to its unique Fe as an N/O chelate. The lateral opening of the incomplete triosephosphate isomerase barrel is covered by the C-terminal part of the protein containing an additional [4Fe-4S] cluster, which is unique to MoaA proteins. Both FeS clusters are separated by approximately 17 angstroms, with a large active site pocket between. The noncysteinyl-ligated unique Fe site of the C-terminal [4Fe-4S] cluster is proposed to be involved in the binding and activation of 5'-GTP.
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Affiliation(s)
- Petra Hänzelmann
- Department of Biochemistry, Center for Structural Biology, State University of New York, Stony Brook, NY 11794-5115, USA
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Martin LL, West LC, Wu B. An extrusion strategy for the FeMo cofactor from nitrogenase. Towards synthetic iron-sulfur proteins. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:5676-86. [PMID: 11722551 DOI: 10.1046/j.0014-2956.2001.02506.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Iron-sulfur clusters are ubiquitous in biological systems, facilitating functions such as electron transfer (rubredoxins, ferredoxins, rieske centres), isomerization (aconitase) and small molecule activation such as dinitrogen reduction (nitrogenases). Of global importance and recently particular interest, is the iron-sulfur-containing iron-molybdenum cofactor (FeMoco) cluster that achieves the biological reduction of dinitrogen under mild conditions. This biologically unique cluster has proved difficult to investigate due to its extreme air sensitivity and the instability of the cluster's structural integrity, outside the protective protein matrix. Here, we report a model iron-sulfur cluster (Roussins black salt (NH(4))[Fe(4)S(3)(NO)(7)]) that has been used to achieve the first example of a metal cluster (guest) embedded within a pseudo-protein, cyclodextrin (host). The product formed is supramolecular, that is, it contained no covalent bonds and was stabilized by predominantly entropy effects. Formation of a 1 : 1 complex between the host and the guest was established for the iron-sulfur cluster with either seven- or eight-membered cyclodextrins (beta- or gamma-cyclodextrin). A range of techniques was used to characterize the new complexes in both the solid and solution states. Electrospray mass spectra indicated the presence of parent ions of the host-guest complexes and electrochemistry was also used to define the redox behavior of the complexes. The iron-sulfur clusters were significantly more stable in the presence of the host cyclodextrin, as revealed by a negative shift for the reduction potential for the host-guest product. Using the beta-cyclodextrin as host, the reduction potential of the iron-sulfur cluster shifted more negative by 60 mV; the effect was even more dramatic for the larger gamma-cyclodextrin where the reduction potential for the cluster was shifted by 90 mV more negative than the 'unbound' [Fe(4)S(3)(NO)(7)]- cluster. This is the first example of a metal cluster, stabilized as a supramolecular complex in a 'host' environment outside of a covalently bonded protein matrix. Creating such stable environments for metal cofactors or clusters that otherwise spontaneously degrade or are catalytically inactive outside the protein matrix could have enormous practical value. Specific implications for the development of extrusion methods for FeMoco from nitrogenase are enormous, with previously difficult, high-energy molecular transformations, such as dinitrogen to ammonia, now more realistically accessible.
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Affiliation(s)
- L L Martin
- Department of Chemistry, Flinders University of South Australia, Adelaide, Australia.
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Jung YS, Bonagura CA, Tilley GJ, Gao-Sheridan HS, Armstrong FA, Stout CD, Burgess BK. Structure of C42D Azotobacter vinelandii FdI. A Cys-X-X-Asp-X-X-Cys motif ligates an air-stable [4Fe-4S]2+/+ cluster. J Biol Chem 2000; 275:36974-83. [PMID: 10961993 DOI: 10.1074/jbc.m004947200] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
All naturally occurring ferredoxins that have Cys-X-X-Asp-X-X-Cys motifs contain [4Fe-4S](2+/+) clusters that can be easily and reversibly converted to [3Fe-4S](+/0) clusters. In contrast, ferredoxins with unmodified Cys-X-X-Cys-X-X-Cys motifs assemble [4Fe-4S](2+/+) clusters that cannot be easily interconverted with [3Fe-4S](+/0) clusters. In this study we changed the central cysteine of the Cys(39)-X-X-Cys(42)-X-X-Cys(45) of Azotobacter vinelandii FdI, which coordinates its [4Fe-4S](2+/+) cluster, into an aspartate. UV-visible, EPR, and CD spectroscopies, metal analysis, and x-ray crystallography show that, like native FdI, aerobically purified C42D FdI is a seven-iron protein retaining its [4Fe-4S](2+/+) cluster with monodentate aspartate ligation to one iron. Unlike known clusters of this type the reduced [4Fe-4S](+) cluster of C42D FdI exhibits only an S = 1/2 EPR with no higher spin signals detected. The cluster shows only a minor change in reduction potential relative to the native protein. All attempts to convert the cluster to a 3Fe cluster using conventional methods of oxygen or ferricyanide oxidation or thiol exchange were not successful. The cluster conversion was ultimately accomplished using a new electrochemical method. Hydrophobic and electrostatic interaction and the lack of Gly residues adjacent to the Asp ligand explain the remarkable stability of this cluster.
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Affiliation(s)
- Y S Jung
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697, USA
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Butt JN, Thornton J, Richardson DJ, Dobbin PS. Voltammetry of a flavocytochrome c(3): the lowest potential heme modulates fumarate reduction rates. Biophys J 2000; 78:1001-9. [PMID: 10653813 PMCID: PMC1300703 DOI: 10.1016/s0006-3495(00)76658-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Iron-induced flavocytochrome c(3), Ifc(3), from Shewanella frigidimarina NCIMB400, derivatized with a 2-pyridyl disulfide label, self-assembles on gold electrodes as a functional array whose fumarate reductase activity as viewed by direct electrochemistry is indistinguishable from that of Ifc(3) adsorbed on gold or graphite electrodes. The enhanced stability of the labeled protein's array permits analysis at a rotating electrode and limiting catalytic currents fit well to a Michaelis-Menten description of enzyme kinetics with K(M) = 56 +/- 20 microM, pH 7.5, comparable to that obtained in solution assays. At fumarate concentrations above 145 microM cyclic voltammetry shows the catalytic response to contain two features. The position and width of the lower potential component centered on -290 mV and corresponding to a one-electron wave implicates the oxidation state of the lowest potential heme of Ifc(3) as a defining feature in the mechanism of fumarate reduction at high turnover rates. We propose the operation of dual pathways for electron transfer to the active site of Ifc(3) with the lowest potential heme acting as an electron relay on one of these pathways.
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Affiliation(s)
- J N Butt
- Schools, Centre for Metalloprotein Spectroscopy and Biology, University of East Anglia, Norwich NR4 7TJ, United Kingdom.
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Synthesis, spectroscopic, redox properties, and DNA cleavage activity of low-spin iron(III) complexes of bleomycin analogues. Inorganica Chim Acta 1999. [DOI: 10.1016/s0020-1693(99)00279-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Hirst J, Duff JLC, Jameson GNL, Kemper MA, Burgess BK, Armstrong FA. Kinetics and Mechanism of Redox-Coupled, Long-Range Proton Transfer in an Iron−Sulfur Protein. Investigation by Fast-Scan Protein-Film Voltammetry. J Am Chem Soc 1998. [DOI: 10.1021/ja980380c] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Judy Hirst
- Contribution from the Department of Chemistry, Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QR, England, and the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92717-3900
| | - Jillian L. C. Duff
- Contribution from the Department of Chemistry, Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QR, England, and the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92717-3900
| | - Guy N. L. Jameson
- Contribution from the Department of Chemistry, Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QR, England, and the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92717-3900
| | - Mary A. Kemper
- Contribution from the Department of Chemistry, Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QR, England, and the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92717-3900
| | - Barbara K. Burgess
- Contribution from the Department of Chemistry, Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QR, England, and the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92717-3900
| | - Fraser A. Armstrong
- Contribution from the Department of Chemistry, Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QR, England, and the Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92717-3900
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Parker VD, Seefeldt LC. A mediated thin-layer voltammetry method for the study of redox protein electrochemistry. Anal Biochem 1997; 247:152-7. [PMID: 9126385 DOI: 10.1006/abio.1997.2049] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A novel mediated thin-layer voltammetry technique that allows the rapid determination of midpoint potentials and electron transfer rate constants for small quantities of redox active proteins is described. Thin-layer voltammograms simulated for an electrolyte containing a redox active protein and an electron transfer mediator show that the rapid homogeneous electron exchange reaction between the protein and the mediator serves to mediate the charge transfer of the protein at the electrode, which does not take place in the absence of the mediator, and results in the observation of an apparently reversible redox couple. Both theoretical and experimental data are presented which suggest that the thin-layer voltammetry method will be generally applicable for the determination of protein redox potentials with the proper selection of mediators. Rate constants for the electron transfer between metalloproteins and mediators can be evaluated by comparing experimental voltammograms with theoretical data from simulations. The technique is demonstrated for the metalloproteins cytochrome c, ferredoxin, and the iron protein of nitrogenase.
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Affiliation(s)
- V D Parker
- Department of Chemistry and Biochemistry, Utah State University, Logan 84322-0300, USA.
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Zhou J, Hu Z, Münck E, Holm RH. The Cuboidal Fe3S4 Cluster: Synthesis, Stability, and Geometric and Electronic Structures in a Non-Protein Environment. J Am Chem Soc 1996. [DOI: 10.1021/ja9537843] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jian Zhou
- Contribution from the Departments of Chemistry, Harvard University, Cambridge, Massachusetts 02138, and Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213
| | - Zhengguo Hu
- Contribution from the Departments of Chemistry, Harvard University, Cambridge, Massachusetts 02138, and Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213
| | - Eckard Münck
- Contribution from the Departments of Chemistry, Harvard University, Cambridge, Massachusetts 02138, and Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213
| | - R. H. Holm
- Contribution from the Departments of Chemistry, Harvard University, Cambridge, Massachusetts 02138, and Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213
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Butt JN, Niles J, Armstrong FA, Breton J, Thomson AJ. Formation and properties of a stable 'high-potential' copper-iron-sulphur cluster in a ferredoxin. NATURE STRUCTURAL BIOLOGY 1994; 1:427-33. [PMID: 7664060 DOI: 10.1038/nsb0794-427] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A ferredoxin isolated from Desulfovibrio africanus contains a [3Fe-4S] cluster that reversibly binds a copper atom, yielding a stable product with a greatly increased reduction potential. The reaction is readily detected in protein molecules adsorbed as a film on an electrode surface. Electron paramagnetic resonance (EPR) and magnetic circular dichroism (MCD) spectra of oxidized and reduced bulk solution products support their assignment as [Cu3Fe-4S]2+ (S = 1/2) and [Cu3Fe-4S]1+ (S = 2) respectively, with copper bound formally as Cu(I). Cyanide causes selective loss of copper and regeneration of the [3Fe-4S] reactant. The results demonstrate the chemical feasibility of CuFeS clusters and suggest that they could exist naturally in biological systems.
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Affiliation(s)
- J N Butt
- Department of Chemistry, University of California, Irvine 92717, USA
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Shen B, Martin LL, Butt JN, Armstrong FA, Stout CD, Jensen GM, Stephens PJ, La Mar GN, Gorst CM, Burgess BK. Azotobacter vinelandii ferredoxin I. Aspartate 15 facilitates proton transfer to the reduced [3Fe-4S] cluster. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(19)74476-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Armstrong FA, Butt JN, Sucheta A. Voltammetric studies of redox-active centers in metalloproteins adsorbed on electrodes. Methods Enzymol 1993; 227:479-500. [PMID: 8255234 DOI: 10.1016/0076-6879(93)27020-h] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- F A Armstrong
- Department of Chemistry, University of California, Irvine 92717
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