1
|
Wilson GS. Spectroelectrochemistry of Proteins. ELECTROANAL 2021. [DOI: 10.1002/elan.202100535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- George S. Wilson
- Department of Chemistry University of Kansas Lawrence, KS USA 1-66045
| |
Collapse
|
2
|
Bellei M, Bortolotti CA, Di Rocco G, Borsari M, Lancellotti L, Ranieri A, Sola M, Battistuzzi G. The influence of the Cys46/Cys55 disulfide bond on the redox and spectroscopic properties of human neuroglobin. J Inorg Biochem 2018; 178:70-86. [DOI: 10.1016/j.jinorgbio.2017.10.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/21/2017] [Accepted: 10/09/2017] [Indexed: 12/21/2022]
|
3
|
Ash PA, Hidalgo R, Vincent KA. Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase. J Vis Exp 2017:55858. [PMID: 29286464 PMCID: PMC5755520 DOI: 10.3791/55858] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Understanding the chemistry of redox proteins demands methods that provide precise control over redox centers within the protein. The technique of protein film electrochemistry, in which a protein is immobilized on an electrode surface such that the electrode replaces physiological electron donors or acceptors, has provided functional insight into the redox reactions of a range of different proteins. Full chemical understanding requires electrochemical control to be combined with other techniques that can add additional structural and mechanistic insight. Here we demonstrate a technique, protein film infrared electrochemistry, which combines protein film electrochemistry with infrared spectroscopic sampling of redox proteins. The technique uses a multiple-reflection attenuated total reflectance geometry to probe a redox protein immobilized on a high surface area carbon black electrode. Incorporation of this electrode into a flow cell allows solution pH or solute concentrations to be changed during measurements. This is particularly powerful in addressing redox enzymes, where rapid catalytic turnover can be sustained and controlled at the electrode allowing spectroscopic observation of long-lived intermediate species in the catalytic mechanism. We demonstrate the technique with experiments on E. coli hydrogenase 1 under turnover (H2 oxidation) and non-turnover conditions.
Collapse
Affiliation(s)
- Philip A Ash
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory
| | - Ricardo Hidalgo
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory
| | - Kylie A Vincent
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory;
| |
Collapse
|
4
|
Schaffner I, Mlynek G, Flego N, Pühringer D, Libiseller-Egger J, Coates L, Hofbauer S, Bellei M, Furtmüller PG, Battistuzzi G, Smulevich G, Djinović-Carugo K, Obinger C. Molecular Mechanism of Enzymatic Chlorite Detoxification: Insights from Structural and Kinetic Studies. ACS Catal 2017; 7:7962-7976. [PMID: 29142780 PMCID: PMC5678291 DOI: 10.1021/acscatal.7b01749] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 09/22/2017] [Indexed: 01/19/2023]
Abstract
![]()
The
heme enzyme chlorite dismutase (Cld) catalyzes the degradation
of chlorite to chloride and dioxygen. Although structure and steady-state
kinetics of Clds have been elucidated, many questions remain (e.g.,
the mechanism of chlorite cleavage and the pH dependence of the reaction).
Here, we present high-resolution X-ray crystal structures of a dimeric
Cld at pH 6.5 and 8.5, its fluoride and isothiocyanate complexes and
the neutron structure at pH 9.0 together with the pH dependence of
the Fe(III)/Fe(II) couple, and the UV–vis and resonance Raman
spectral features. We demonstrate that the distal Arg127 cannot act
as proton acceptor and is fully ionized even at pH 9.0 ruling out
its proposed role in dictating the pH dependence of chlorite degradation.
Stopped-flow studies show that (i) Compound I and hypochlorite do
not recombine and (ii) Compound II is the immediately formed redox
intermediate that dominates during turnover. Homolytic cleavage of
chlorite is proposed.
Collapse
Affiliation(s)
- Irene Schaffner
- Department
of Chemistry, Division of Biochemistry, BOKU—University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Georg Mlynek
- Department
for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, A-1030 Vienna, Austria
| | - Nicola Flego
- Dipartimento
di Chimica “Ugo Schiff”, Università di Firenze, Via della
Lastruccia 3-13, I-50019 Sesto Fiorentino (FI), Italy
| | - Dominic Pühringer
- Department
for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, A-1030 Vienna, Austria
| | - Julian Libiseller-Egger
- Department
of Chemistry, Division of Biochemistry, BOKU—University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Leighton Coates
- Biology
and Soft Matter Division, Oak Ridge National Laboratory, 1 Bethel
Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Stefan Hofbauer
- Department
of Chemistry, Division of Biochemistry, BOKU—University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Marzia Bellei
- Department
of Life Sciences, University of Modena and Reggio Emilia, Via Campi
103, 41125 Modena, Italy
| | - Paul G. Furtmüller
- Department
of Chemistry, Division of Biochemistry, BOKU—University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Gianantonio Battistuzzi
- Department
of Chemistry and Geology, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - Giulietta Smulevich
- Dipartimento
di Chimica “Ugo Schiff”, Università di Firenze, Via della
Lastruccia 3-13, I-50019 Sesto Fiorentino (FI), Italy
| | - Kristina Djinović-Carugo
- Department
for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, A-1030 Vienna, Austria
- Department
of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Christian Obinger
- Department
of Chemistry, Division of Biochemistry, BOKU—University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| |
Collapse
|
5
|
El Khoury Y, Van Wilderen LJGW, Bredenbeck J. Ultrafast 2D-IR spectroelectrochemistry of flavin mononucleotide. J Chem Phys 2016; 142:212416. [PMID: 26049436 DOI: 10.1063/1.4916916] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We demonstrate the coupling of ultrafast two-dimensional infrared (2D-IR) spectroscopy to electrochemistry in solution and apply it to flavin mononucleotide, an important cofactor of redox proteins. For this purpose, we designed a spectroelectrochemical cell optimized for 2D-IR measurements in reflection and measured the time-dependent 2D-IR spectra of the oxidized and reduced forms of flavin mononucleotide. The data show anharmonic coupling and vibrational energy transfer between different vibrational modes in the two redox species. Such information is inaccessible with redox-controlled steady-state FTIR spectroscopy. The wide range of applications offered by 2D-IR spectroscopy, such as sub-picosecond structure determination, IR band assignment via energy transfer, disentangling reaction mixtures through band connectivity in the 2D spectra, and the measurement of solvation dynamics and chemical exchange can now be explored under controlled redox potential. The development of this technique furthermore opens new horizons for studying the dynamics of redox proteins.
Collapse
Affiliation(s)
- Youssef El Khoury
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main, Germany
| | - Luuk J G W Van Wilderen
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main, Germany
| | - Jens Bredenbeck
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main, Germany
| |
Collapse
|
6
|
El Khoury Y, Van Wilderen LJGW, Vogt T, Winter E, Bredenbeck J. A spectroelectrochemical cell for ultrafast two-dimensional infrared spectroscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:083102. [PMID: 26329169 DOI: 10.1063/1.4927533] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A spectroelectrochemical cell has been designed to combine electrochemistry and ultrafast two-dimensional infrared (2D-IR) spectroscopy, which is a powerful tool to extract structure and dynamics information on the femtosecond to picosecond time scale. Our design is based on a gold mirror with the dual role of performing electrochemistry and reflecting IR light. To provide the high optical surface quality required for laser spectroscopy, the gold surface is made by electron beam evaporation on a glass substrate. Electrochemical cycling facilitates in situ collection of ultrafast dynamics of redox-active molecules by means of 2D-IR. The IR beams are operated in reflection mode so that they travel twice through the sample, i.e., the signal size is doubled. This methodology is optimal for small sample volumes and successfully tested with the ferricyanide/ferrocyanide redox system of which the corresponding electrochemically induced 2D-IR difference spectrum is reported.
Collapse
Affiliation(s)
- Youssef El Khoury
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt, Germany
| | - Luuk J G W Van Wilderen
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt, Germany
| | - Tim Vogt
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt, Germany
| | - Ernst Winter
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt, Germany
| | - Jens Bredenbeck
- Institut für Biophysik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, 60438 Frankfurt, Germany
| |
Collapse
|
7
|
Schaffner I, Hofbauer S, Krutzler M, Pirker KF, Bellei M, Stadlmayr G, Mlynek G, Djinovic-Carugo K, Battistuzzi G, Furtmüller PG, Daims H, Obinger C. Dimeric chlorite dismutase from the nitrogen-fixing cyanobacterium Cyanothece sp. PCC7425. Mol Microbiol 2015; 96:1053-68. [PMID: 25732258 PMCID: PMC4973843 DOI: 10.1111/mmi.12989] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2015] [Indexed: 11/28/2022]
Abstract
It is demonstrated that cyanobacteria (both azotrophic and non-azotrophic) contain heme b oxidoreductases that can convert chlorite to chloride and molecular oxygen (incorrectly denominated chlorite 'dismutase', Cld). Beside the water-splitting manganese complex of photosystem II, this metalloenzyme is the second known enzyme that catalyses the formation of a covalent oxygen-oxygen bond. All cyanobacterial Clds have a truncated N-terminus and are dimeric (i.e. clade 2) proteins. As model protein, Cld from Cyanothece sp. PCC7425 (CCld) was recombinantly produced in Escherichia coli and shown to efficiently degrade chlorite with an activity optimum at pH 5.0 [kcat 1144 ± 23.8 s(-1), KM 162 ± 10.0 μM, catalytic efficiency (7.1 ± 0.6) × 10(6) M(-1) s(-1)]. The resting ferric high-spin axially symmetric heme enzyme has a standard reduction potential of the Fe(III)/Fe(II) couple of -126 ± 1.9 mV at pH 7.0. Cyanide mediates the formation of a low-spin complex with k(on) = (1.6 ± 0.1) × 10(5) M(-1) s(-1) and k(off) = 1.4 ± 2.9 s(-1) (KD ∼ 8.6 μM). Both, thermal and chemical unfolding follows a non-two-state unfolding pathway with the first transition being related to the release of the prosthetic group. The obtained data are discussed with respect to known structure-function relationships of Clds. We ask for the physiological substrate and putative function of these O2 -producing proteins in (nitrogen-fixing) cyanobacteria.
Collapse
Affiliation(s)
- Irene Schaffner
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Stefan Hofbauer
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria.,Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Michael Krutzler
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Katharina F Pirker
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Marzia Bellei
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125, Modena, Italy
| | - Gerhard Stadlmayr
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Georg Mlynek
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Kristina Djinovic-Carugo
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria.,Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Gianantonio Battistuzzi
- Department of Chemistry and Geology, University of Modena and Reggio Emilia, 41125, Modena, Italy
| | - Paul G Furtmüller
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| | - Holger Daims
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, University of Vienna, Vienna, Austria
| | - Christian Obinger
- Department of Chemistry, Division of Biochemistry, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190, Vienna, Austria
| |
Collapse
|
8
|
Liu J, Chakraborty S, Hosseinzadeh P, Yu Y, Tian S, Petrik I, Bhagi A, Lu Y. Metalloproteins containing cytochrome, iron-sulfur, or copper redox centers. Chem Rev 2014; 114:4366-469. [PMID: 24758379 PMCID: PMC4002152 DOI: 10.1021/cr400479b] [Citation(s) in RCA: 560] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Indexed: 02/07/2023]
Affiliation(s)
- Jing Liu
- Department of Chemistry, Department of Biochemistry, and Center for Biophysics
and Computational
Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Saumen Chakraborty
- Department of Chemistry, Department of Biochemistry, and Center for Biophysics
and Computational
Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Parisa Hosseinzadeh
- Department of Chemistry, Department of Biochemistry, and Center for Biophysics
and Computational
Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Yang Yu
- Department of Chemistry, Department of Biochemistry, and Center for Biophysics
and Computational
Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Shiliang Tian
- Department of Chemistry, Department of Biochemistry, and Center for Biophysics
and Computational
Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Igor Petrik
- Department of Chemistry, Department of Biochemistry, and Center for Biophysics
and Computational
Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Ambika Bhagi
- Department of Chemistry, Department of Biochemistry, and Center for Biophysics
and Computational
Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Yi Lu
- Department of Chemistry, Department of Biochemistry, and Center for Biophysics
and Computational
Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| |
Collapse
|
9
|
Ash PA, Vincent KA. Spectroscopic analysis of immobilised redox enzymes under direct electrochemical control. Chem Commun (Camb) 2011; 48:1400-9. [PMID: 22057715 DOI: 10.1039/c1cc15871f] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This article reviews recent developments in spectroscopic analysis of electrode-immobilised enzymes under direct, unmediated electrochemical control. These methods unite the suite of spectroscopic methods available for characterisation of structural, electronic and coordination changes in proteins with the exquisite control over complex redox enzymes that can be achieved in protein film electrochemistry in which immobilised protein molecules exchange electrons directly with an electrode. This combination is particularly powerful in studies of highly active enzymes where redox states can be controlled even under fast electrocatalytic turnover. We examine examples in which UV-visible, IR, Raman and MCD spectroscopy have been combined with direct electrochemistry to probe redox-dependent chemistry, and consider future opportunities for 'direct' spectroelectrochemistry of immobilised enzymes.
Collapse
Affiliation(s)
- Philip A Ash
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | | |
Collapse
|
10
|
Wu SP, Bellei M, Mansy SS, Battistuzzi G, Sola M, Cowan JA. Redox chemistry of the Schizosaccharomyces pombe ferredoxin electron-transfer domain and influence of Cys to Ser substitutions. J Inorg Biochem 2011; 105:806-11. [PMID: 21497579 DOI: 10.1016/j.jinorgbio.2011.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 01/29/2011] [Accepted: 03/10/2011] [Indexed: 11/26/2022]
Abstract
Schizosaccharomyces pombe (Sp) ferredoxin contains a C-terminal electron transfer protein ferredoxin domain (etp(Fd)) that is homologous to adrenodoxin. The ferredoxin has been characterized by spectroelectrochemical methods, and Mössbauer, UV-Vis and circular dichroism spectroscopies. The Mössbauer spectrum is consistent with a standard diferric [2Fe-2S](2+) cluster. While showing sequence homology to vertebrate ferredoxins, the E°' and the reduction thermodynamics for etp(Fd) (-0.392 V) are similar to plant-type ferredoxins. Relatively stable Cys to Ser derivatives were made for each of the four bound Cys residues and variations in the visible spectrum in the 380-450 nm range were observed that are characteristic of oxygen ligated clusters, including members of the [2Fe-2S] cluster IscU/ISU scaffold proteins. Circular dichroism spectra were similar and consistent with no significant structural change accompanying these mutations. All derivatives were active in an NADPH-Fd reductase cytochrome c assay. The binding affinity of Fd to the reductase was similar, however, V(max) reflecting rate limiting electron transfer was found to decrease ~13-fold. The data are consistent with relatively minor perturbations of both the electronic properties of the cluster following substitution of the Fe-bond S atom with O, and the electronic coupling of the cluster to the protein.
Collapse
Affiliation(s)
- Shu-pao Wu
- Evans Laboratory of Chemistry, Ohio State University, Columbus, OH 43210, USA
| | | | | | | | | | | |
Collapse
|
11
|
Ludwig R, Harreither W, Tasca F, Gorton L. Cellobiose Dehydrogenase: A Versatile Catalyst for Electrochemical Applications. Chemphyschem 2010; 11:2674-97. [DOI: 10.1002/cphc.201000216] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
12
|
Wilson RA, Pinyayev TS, Membreno N, Heineman WR. Rapid Prototyped Optically Transparent Thin-Layer Electrode Holder for Spectroelectrochemistry in Bench-Top Spectrophotometers. ELECTROANAL 2010. [DOI: 10.1002/elan.201000267] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
13
|
Bellei M, Battistuzzi G, Wu SP, Mansy SS, Cowan JA, Sola M. Control of reduction thermodynamics in [2Fe-2S] ferredoxins Entropy-enthalpy compensation and the influence of surface mutations. J Inorg Biochem 2010; 104:691-6. [PMID: 20362339 DOI: 10.1016/j.jinorgbio.2010.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 03/04/2010] [Accepted: 03/04/2010] [Indexed: 11/27/2022]
Abstract
The reaction thermodynamics for the one-electron reduction of the [2Fe-2S] cluster of both human ferredoxin and various surface point mutants, in which each of the negatively charged residues Asp72, Glu73, Asp76, and Asp79 were converted to Ala, have been determined by variable temperature spectroelectrochemical measurements. The above are conserved residues that have been implicated in interactions between the vertebrate-type ferredoxins and their redox partners. In all cases, and similar to other 2Fe-ferredoxins, the reduction potentials are negative as a result of both an enthalpic and entropic stabilization of the oxidized state. Although all Hs Fd mutants, with the exception of Asp72Ala, show slightly higher E degrees ' values than that of wild type Hs Fd, according to expectations for a purely electrostatic model, they exhibit changes in the H degrees '(rc) values that are electrostatically counter-intuitive. The observation of enthalpy-entropy compensation within the protein series indicates that the mutation-induced changes in H degrees '(rc) and S degrees '(rc) are dominated by reduction-induced solvent reorganization effects. Protein-based entropic effects are likely to be responsible for the low E degrees ' value of D72A.
Collapse
Affiliation(s)
- Marzia Bellei
- Department of Chemistry, University of Modena and Reggio Emilia, Via Campi, 183, 41100 Modena, Italy
| | | | | | | | | | | |
Collapse
|
14
|
Battistuzzi G, Bellei M, Vlasits J, Banerjee S, Furtmüller PG, Sola M, Obinger C. Redox thermodynamics of lactoperoxidase and eosinophil peroxidase. Arch Biochem Biophys 2009; 494:72-7. [PMID: 19944669 DOI: 10.1016/j.abb.2009.11.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 11/10/2009] [Accepted: 11/13/2009] [Indexed: 10/20/2022]
Abstract
Eosinophil peroxidase (EPO) and lactoperoxidase (LPO) are important constituents of the innate immune system of mammals. These heme enzymes belong to the peroxidase-cyclooxygenase superfamily and catalyze the oxidation of thiocyanate, bromide and nitrite to hypothiocyanate, hypobromous acid and nitrogen dioxide that are toxic for invading pathogens. In order to gain a better understanding of the observed differences in substrate specificity and oxidation capacity in relation to heme and protein structure, a comprehensive spectro-electrochemical investigation was performed. The reduction potential (E degrees ') of the Fe(III)/Fe(II) couple of EPO and LPO was determined to be -126mV and -176mV, respectively (25 degrees C, pH 7.0). Variable temperature experiments show that EPO and LPO feature different reduction thermodynamics. In particular, reduction of ferric EPO is enthalpically and entropically disfavored, whereas in LPO the entropic term, which selectively stabilizes the oxidized form, prevails on the enthalpic term that favors reduction of Fe(III). The data are discussed with respect to the architecture of the heme cavity and the substrate channel. Comparison with published data for myeloperoxidase demonstrates the effect of heme to protein linkages and heme distortion on the redox chemistry of mammalian peroxidases and in consequence on the enzymatic properties of these physiologically important oxidoreductases.
Collapse
Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry, University of Modena and Reggio Emilia, via Campi 183, Modena, Italy.
| | | | | | | | | | | | | |
Collapse
|
15
|
Koay M, Antonkine M, Gärtner W, Lubitz W. Modelling Low-Potential [Fe4S4] Clusters in Proteins. Chem Biodivers 2008; 5:1571-1587. [DOI: 10.1002/cbdv.200890145] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
16
|
Battistuzzi G, Bellei M, Casella L, Bortolotti CA, Roncone R, Monzani E, Sola M. Redox reactivity of the heme Fe3+/Fe2+ couple in native myoglobins and mutants with peroxidase-like activity. J Biol Inorg Chem 2007; 12:951-8. [PMID: 17576605 DOI: 10.1007/s00775-007-0267-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Accepted: 05/21/2007] [Indexed: 10/23/2022]
Abstract
The reaction enthalpy and entropy for the one-electron reduction of the ferric heme in horse heart and sperm whale aquometmyoglobins (Mb) have been determined exploiting a spectroelectrochemical approach. Also investigated were the T67R, T67K, T67R/S92D and T67R/S92D Mb-H variants (the latter containing a protoheme-L: -histidine methyl ester) of sperm whale Mb, which feature peroxidase-like activity. The reduction potential (E degrees ') in all species consists of an enthalpic term which disfavors Fe(3+) reduction and a larger entropic contribution which instead selectively stabilizes the reduced form. This behavior differs from that of the heme redox enzymes and electron transport proteins investigated so far. The reduction thermodynamics in the series of sperm whale Mb variants show an almost perfect enthalpy-entropy compensation, indicating that the mutation-induced changes in DeltaH(o')(rc) and DeltaS(o')(rc) are dominated by reduction-induced solvent reorganization effects. The modest changes in E degrees ' originate from the enthalpic effects of the electrostatic interactions of the heme with the engineered charged residues. The small influence that the mutations exert on the reduction potential of myoglobin suggests that the increased peroxidase activity of the variants is not related to changes in the redox reactivity of the heme iron, but are likely related to a more favored substrate orientation within the distal heme cavity.
Collapse
Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, 41100 Modena, Italy
| | | | | | | | | | | | | |
Collapse
|
17
|
Battistuzzi G, Bellei M, Borsari M, Di Rocco G, Ranieri A, Sola M. Axial ligation and polypeptide matrix effects on the reduction potential of heme proteins probed on their cyanide adducts. J Biol Inorg Chem 2005; 10:643-51. [PMID: 16133205 DOI: 10.1007/s00775-005-0014-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Accepted: 07/25/2005] [Indexed: 10/25/2022]
Abstract
The enthalpic and entropic changes accompanying the reduction reaction of the six-coordinate cyanide adducts of cytochrome c, microperoxidase-11 and a few plant peroxidases were measured electrochemically. Once the compensating changes in reduction enthalpy and entropy due to solvent reorganization effects are factorized out, it is found that cyanide binding stabilizes enthalpically the ferriheme following the order: cyochrome c > peroxidase > microperoxidase-11. The effect is inversely correlated to the solvent accessibility of the heme. Comparison of the reduction thermodynamics for the cyanide adducts of cytochrome c and plant peroxidases with those for microperoxidase-11 and myoglobin, respectively, yielded an estimate of the consequences of protein encapsulation and of the anionic character of the proximal histidine on the reduction potential of the heme-cyanide group. Insertion of the heme-CN group into the folded peptide chain of cyt c induces an enthalpy-based decrease in E degrees ' of approximately 100 mV, consistent with the lower net charge of the oxidized as compared to the reduced iron center, whereas a full imidazolate character of the proximal histidine stabilizes enthalpically the ferriheme by approximately 400 mV. The latter value should be best considered as an upper limit since it also includes some solvation effects arising from the nature of the protein systems being compared.
Collapse
Affiliation(s)
- G Battistuzzi
- Department of Chemistry and Centro SCS, University of Modena and Reggio Emilia, via Campi 183, 41100, Modena, Italy
| | | | | | | | | | | |
Collapse
|
18
|
Battistuzzi G, Bellei M, Leonardi A, Pierattelli R, De Candia A, Vila AJ, Sola M. Reduction thermodynamics of the T1 Cu site in plant and fungal laccases. J Biol Inorg Chem 2005; 10:867-73. [PMID: 16231129 DOI: 10.1007/s00775-005-0035-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Accepted: 09/19/2005] [Indexed: 10/25/2022]
Abstract
The thermodynamic parameters for reduction of the type-1 (T1) copper site in Rhus vernicifera and Trametes versicolor laccases and for the derivative of the former protein from which the type-2 copper has been selectively removed (T2D) have been determined with UV-vis spectroelectrochemistry. In all cases, the enthalpic term turns out to be the main determinant of the Eo' of the T1 site. Also the difference between the reduction potentials of the two laccases is enthalpy-based and reflects differences in the coordination features of the T1 sites and their protein environment. The T1 sites in native R. vernicifera laccase and its T2D derivative show the same Eo', as a result of compensatory differences in the reduction thermodynamics. This suggests that removal of the type-2 (T2) copper results in modification of the reduction-induced solvent reorganization effects, with no influence in the structure of the multicopper protein site. This conclusion is supported by NMR data recorded on the native, the T2D, and Hg-substituted T1 derivatives of R. vernicifera laccase, which show that the T1 and T2/T3 sites are largely noninteracting.
Collapse
Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry-Centro SCS, University of Modena and Reggio Emilia, Via Campi 183, 41100, Modena, Italy.
| | | | | | | | | | | | | |
Collapse
|
19
|
Tsujimura S, Kuriyama A, Fujieda N, Kano K, Ikeda T. Mediated spectroelectrochemical titration of proteins for redox potential measurements by a separator-less one-compartment bulk electrolysis method. Anal Biochem 2005; 337:325-31. [PMID: 15691513 DOI: 10.1016/j.ab.2004.11.017] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Indexed: 11/16/2022]
Abstract
One-compartment bulk electrolysis and simultaneous spectroscopic measurements are realized in a conventional spectroscopic cuvette without separator by using a mesh-type working electrode with extremely large surface area and a wire-type counter electrode with very small surface area. Spectrophotometric monitoring revealed complete electrolysis in a first-order kinetics. This technique was applied to mediated titration of cytochrome c and bilirubin oxidase for determining their redox potentials. Kinetics for the solution redox reaction between protein and mediator is described. The subtraction of spectral background due to mediator adsorption is very easy because of high reproducibility. The experiments can be done under completely anaerobic conditions. Low-absorbance protein samples (of low concentrations or small absorption coefficients) and hydrophobic proteins (such as membrane-bound proteins) are acceptable for measurements.
Collapse
Affiliation(s)
- Seiya Tsujimura
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | | | | | | | | |
Collapse
|
20
|
Battistuzzi G, Bellei M, Bortolotti CA, Rocco GD, Leonardi A, Sola M. Characterization of the solution reactivity of a basic heme peroxidase from Cucumis sativus. Arch Biochem Biophys 2004; 423:317-31. [PMID: 15001396 DOI: 10.1016/j.abb.2003.12.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2003] [Revised: 12/10/2003] [Indexed: 10/26/2022]
Abstract
A basic heme peroxidase has been isolated from cucumber (Cucumis sativus) peelings and characterized through electronic and (1)H NMR spectra from pH 3 to 11. The protein, as isolated, contains a high-spin ferriheme which in the low pH region is sensitive to two acid-base equilibria with apparent pK(a) values of approximately 5 and 3.6, assigned to the distal histidine and to a heme propionate, respectively. At high pH, a new low-spin species develops with an apparent pK(a) of 11, likely due to the binding of an hydroxide ion to the sixth (axial) coordination position of the Fe(III). A number of acid-base equilibria involving heme propionates and residues in the distal cavity also affect the binding of inorganic anions such as cyanide, azide, and fluoride to the ferriheme, as well as the catalytic activity. The reduction potentials of the native protein and of its cyanide derivative, determined through UV-Vis spectroelectrochemistry, result to be -0.320+/-0.015 and -0.412+/-0.010V, respectively. Overall, the reactivity of this protein parallels those of other plant peroxidases, especially horseradish peroxidase. However, some differences exist in the acid-base equilibria affecting its reactivity and in the reduction potential, likely as a result of small structural differences in the heme distal and proximal cavities.
Collapse
Affiliation(s)
- Gianantonio Battistuzzi
- Department of Chemistry, Centro SCS, University of Modena and Reggio Emilia, Via Campi 183, Modena 41100, Italy
| | | | | | | | | | | |
Collapse
|
21
|
KANO K, IKEDA T. Bioelectrocatalysis, Powerful Means of Connecting Electrochemistry to Biochemistry and Biotechnology. ELECTROCHEMISTRY 2003. [DOI: 10.5796/electrochemistry.71.86] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Kenji KANO
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Tokuji IKEDA
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| |
Collapse
|
22
|
Taboy CH, Bonaventura C, Crumbliss AL. Anaerobic oxidations of myoglobin and hemoglobin by spectroelectrochemistry. Methods Enzymol 2002; 353:187-209. [PMID: 12078494 DOI: 10.1016/s0076-6879(02)53048-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Céline H Taboy
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | | | | |
Collapse
|
23
|
|
24
|
Torimura M, Mochizuki M, Kano K, Ikeda T, Ueda T. Mediator-Assisted Continuous-Flow Column Electrolytic Spectroelectrochemical Technique for the Measurement of Protein Redox Potentials. Application to Peroxidase. Anal Chem 1998. [DOI: 10.1021/ac980621z] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Masaki Torimura
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, and Chromatographic Instruments Division, Shimadzu Corporation, Nakagyo-ku, Kyoto 604-8511, Japan
| | - Manabu Mochizuki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, and Chromatographic Instruments Division, Shimadzu Corporation, Nakagyo-ku, Kyoto 604-8511, Japan
| | - Kenji Kano
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, and Chromatographic Instruments Division, Shimadzu Corporation, Nakagyo-ku, Kyoto 604-8511, Japan
| | - Tokuji Ikeda
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, and Chromatographic Instruments Division, Shimadzu Corporation, Nakagyo-ku, Kyoto 604-8511, Japan
| | - Teruhisa Ueda
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, and Chromatographic Instruments Division, Shimadzu Corporation, Nakagyo-ku, Kyoto 604-8511, Japan
| |
Collapse
|