1
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Schweitzer-Stenner R. Probing the versatility of cytochrome c by spectroscopic means: A Laudatio on resonance Raman spectroscopy. J Inorg Biochem 2024; 259:112641. [PMID: 38901065 DOI: 10.1016/j.jinorgbio.2024.112641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 06/03/2024] [Accepted: 06/12/2024] [Indexed: 06/22/2024]
Abstract
Over the last 50 years resonance Raman spectroscopy has become an invaluable tool for the exploration of chromophores in biological macromolecules. Among them, heme proteins and metal complexes have attracted considerable attention. This interest results from the fact that resonance Raman spectroscopy probes the vibrational dynamics of these chromophores without direct interference from the surrounding. However, the indirect influence via through-bond and through-space chromophore-protein interactions can be conveniently probed and analyzed. This review article illustrates this point by focusing on class 1 cytochrome c, a comparatively simple heme protein generally known as electron carrier in mitochondria. The article demonstrates how through selective excitation of resonance Raman active modes information about the ligation, the redox state and the spin state of the heme iron can be obtained from band positions in the Raman spectra. The investigation of intensities and depolarization ratios emerged as tools for the analysis of in-plane and out-of-plane deformations of the heme macrocycle. The article further shows how resonance Raman spectroscopy was used to characterize partially unfolded states of oxidized cytochrome c. Finally, it describes its use for exploring structural changes due to the protein's binding to anionic surfaces like cardiolipin containing membranes.
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2
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Portela PC, Shipps CC, Shen C, Srikanth V, Salgueiro CA, Malvankar NS. Widespread extracellular electron transfer pathways for charging microbial cytochrome OmcS nanowires via periplasmic cytochromes PpcABCDE. Nat Commun 2024; 15:2434. [PMID: 38509081 PMCID: PMC10954620 DOI: 10.1038/s41467-024-46192-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 02/19/2024] [Indexed: 03/22/2024] Open
Abstract
Extracellular electron transfer (EET) via microbial nanowires drives globally-important environmental processes and biotechnological applications for bioenergy, bioremediation, and bioelectronics. Due to highly-redundant and complex EET pathways, it is unclear how microbes wire electrons rapidly (>106 s-1) from the inner-membrane through outer-surface nanowires directly to an external environment despite a crowded periplasm and slow (<105 s-1) electron diffusion among periplasmic cytochromes. Here, we show that Geobacter sulfurreducens periplasmic cytochromes PpcABCDE inject electrons directly into OmcS nanowires by binding transiently with differing efficiencies, with the least-abundant cytochrome (PpcC) showing the highest efficiency. Remarkably, this defined nanowire-charging pathway is evolutionarily conserved in phylogenetically-diverse bacteria capable of EET. OmcS heme reduction potentials are within 200 mV of each other, with a midpoint 82 mV-higher than reported previously. This could explain efficient EET over micrometres at ultrafast (<200 fs) rates with negligible energy loss. Engineering this minimal nanowire-charging pathway may yield microbial chassis with improved performance.
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Affiliation(s)
- Pilar C Portela
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
- UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Catharine C Shipps
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Cong Shen
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Vishok Srikanth
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Carlos A Salgueiro
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal.
- UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal.
| | - Nikhil S Malvankar
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
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3
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Paradisi A, Bellei M, Bortolotti CA, Di Rocco G, Ranieri A, Borsari M, Sola M, Battistuzzi G. Effects of removal of the axial methionine heme ligand on the binding of S. cerevisiae iso-1 cytochrome c to cardiolipin. J Inorg Biochem 2024; 252:112455. [PMID: 38141433 DOI: 10.1016/j.jinorgbio.2023.112455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 12/05/2023] [Accepted: 12/13/2023] [Indexed: 12/25/2023]
Abstract
The cleavage of the axial S(Met) - Fe bond in cytochrome c (cytc) upon binding to cardiolipin (CL), a glycerophospholipid of the inner mitochondrial membrane, is one of the key molecular changes that impart cytc with (lipo)peroxidase activity essential to its pro-apoptotic function. In this work, UV - VIS, CD, MCD and fluorescence spectroscopies were used to address the role of the Fe - M80 bond in controlling the cytc-CL interaction, by studying the binding of the Met80Ala (M80A) variant of S. cerevisiae iso-1 cytc (ycc) to CL liposomes in comparison with the wt protein [Paradisi et al. J. Biol. Inorg. Chem. 25 (2020) 467-487]. The results show that the integrity of the six-coordinate heme center along with the distal heme site containing the Met80 ligand is a not requisite for cytc binding to CL. Indeed, deletion of the Fe - S(Met80) bond has a little impact on the mechanism of ycc-CL interaction, although it results in an increased heme accessibility to solvent and a reduced structural stability of the protein. In particular, M80A features a slightly tighter binding to CL at low CL/cytc ratios compared to wt ycc, possibly due to the lift of some constraints to the insertion of the CL acyl chains into the protein hydrophobic core. M80A binding to CL maintains the dependence on the CL-to-cytc mixing scheme displayed by the wt species.
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Affiliation(s)
- Alessandro Paradisi
- Department of Life Sciences, University of Modena and Reggio Emilia, via Campi 103, 41126 Modena, Italy
| | - Marzia Bellei
- Department of Life Sciences, University of Modena and Reggio Emilia, via Campi 103, 41126 Modena, Italy
| | - Carlo Augusto Bortolotti
- Department of Life Sciences, University of Modena and Reggio Emilia, via Campi 103, 41126 Modena, Italy
| | - Giulia Di Rocco
- Department of Life Sciences, University of Modena and Reggio Emilia, via Campi 103, 41126 Modena, Italy
| | - Antonio Ranieri
- Department of Life Sciences, University of Modena and Reggio Emilia, via Campi 103, 41126 Modena, Italy
| | - Marco Borsari
- Department of Chemistry and Geology, University of Modena and Reggio Emilia, via Campi 103, 41126 Modena, Italy
| | - Marco Sola
- Department of Life Sciences, University of Modena and Reggio Emilia, via Campi 103, 41126 Modena, Italy
| | - Gianantonio Battistuzzi
- Department of Chemistry and Geology, University of Modena and Reggio Emilia, via Campi 103, 41126 Modena, Italy.
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4
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Zhang X, Joyce GH, Leu AO, Zhao J, Rabiee H, Virdis B, Tyson GW, Yuan Z, McIlroy SJ, Hu S. Multi-heme cytochrome-mediated extracellular electron transfer by the anaerobic methanotroph 'Candidatus Methanoperedens nitroreducens'. Nat Commun 2023; 14:6118. [PMID: 37777538 PMCID: PMC10542353 DOI: 10.1038/s41467-023-41847-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 09/18/2023] [Indexed: 10/02/2023] Open
Abstract
Anaerobic methanotrophic archaea (ANME) carry out anaerobic oxidation of methane, thus playing a crucial role in the methane cycle. Previous genomic evidence indicates that multi-heme c-type cytochromes (MHCs) may facilitate the extracellular electron transfer (EET) from ANME to different electron sinks. Here, we provide experimental evidence supporting cytochrome-mediated EET for the reduction of metals and electrodes by 'Candidatus Methanoperedens nitroreducens', an ANME acclimated to nitrate reduction. Ferrous iron-targeted fluorescent assays, metatranscriptomics, and single-cell imaging suggest that 'Ca. M. nitroreducens' uses surface-localized redox-active cytochromes for metal reduction. Electrochemical and Raman spectroscopic analyses also support the involvement of c-type cytochrome-mediated EET for electrode reduction. Furthermore, several genes encoding menaquinone cytochrome type-c oxidoreductases and extracellular MHCs are differentially expressed when different electron acceptors are used.
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Affiliation(s)
- Xueqin Zhang
- Australian Centre for Water and Environmental Biotechnology (ACWEB), Faculty of Engineering, Architecture and Information Technology, University of Queensland, Brisbane, Australia
| | - Georgina H Joyce
- Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology (QUT), Translational Research Institute, Woolloongabba, Australia
| | - Andy O Leu
- Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology (QUT), Translational Research Institute, Woolloongabba, Australia
| | - Jing Zhao
- Australian Centre for Water and Environmental Biotechnology (ACWEB), Faculty of Engineering, Architecture and Information Technology, University of Queensland, Brisbane, Australia
- Ecological Engineering of Mine Wastes, Sustainable Minerals Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Hesamoddin Rabiee
- Australian Centre for Water and Environmental Biotechnology (ACWEB), Faculty of Engineering, Architecture and Information Technology, University of Queensland, Brisbane, Australia
- School of Chemical Engineering, The University of Queensland, Brisbane, QLD, Australia
- Centre for Future Materials, University of Southern Queensland, Springfield, QLD, Australia
| | - Bernardino Virdis
- Australian Centre for Water and Environmental Biotechnology (ACWEB), Faculty of Engineering, Architecture and Information Technology, University of Queensland, Brisbane, Australia
| | - Gene W Tyson
- Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology (QUT), Translational Research Institute, Woolloongabba, Australia
| | - Zhiguo Yuan
- Australian Centre for Water and Environmental Biotechnology (ACWEB), Faculty of Engineering, Architecture and Information Technology, University of Queensland, Brisbane, Australia
- School of Energy and Environment, City University of Hong Kong, Hong Kong SAR, China
| | - Simon J McIlroy
- Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology (QUT), Translational Research Institute, Woolloongabba, Australia
| | - Shihu Hu
- Australian Centre for Water and Environmental Biotechnology (ACWEB), Faculty of Engineering, Architecture and Information Technology, University of Queensland, Brisbane, Australia.
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5
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Palermo JC, Carllinni Colombo M, Semelak JA, Scocozza MF, Boubeta FM, Murgida DH, Estrin DA, Bari SE. Autocatalytic Mechanism in the Anaerobic Reduction of Metmyoglobin by Sulfide Species. Inorg Chem 2023; 62:11304-11317. [PMID: 37439562 DOI: 10.1021/acs.inorgchem.3c00593] [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: 07/14/2023]
Abstract
The mechanism of the metal centered reduction of metmyoglobin (MbFeIII) by sulfide species (H2S/HS-) under an argon atmosphere has been studied by a combination of spectroscopic, kinetic, and computational methods. Asymmetric S-shaped time-traces for the formation of MbFeII at varying ratios of excess sulfide were observed at pH 5.3 < pH < 8.0 and 25 °C, suggesting an autocatalytic reaction mechanism. An increased rate at more alkaline pHs points to HS- as relevant reactive species for the reduction. The formation of the sulfanyl radical (HS•) in the slow initial phase was assessed using the spin-trap phenyl N-tert-butyl nitrone. This radical initiates the formation of S-S reactive species as disulfanuidyl/ disulfanudi-idyl radical anions and disulfide (HSSH•-/HSS•2- and HSS-, respectively). The autocatalysis has been ascribed to HSS-, formed after HSSH•-/HSS•2- disproportionation, which behaves as a fast reductant toward the intermediate complex MbFeIII(HS-). We propose a reaction mechanism for the sulfide-mediated reduction of metmyoglobin where only ferric heme iron initiates the oxidation of sulfide species. Beside the chemical interest, this insight into the MbFeIII/sulfide reaction under an argon atmosphere is relevant for the interpretation of biochemical aspects of ectopic myoglobins found on hypoxic tissues toward reactive sulfur species.
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Affiliation(s)
- Juan Cruz Palermo
- Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
| | - Melisa Carllinni Colombo
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
| | - Jonathan A Semelak
- Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
| | - Magalí F Scocozza
- Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
| | - Fernando M Boubeta
- Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
| | - Daniel H Murgida
- Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
| | - Darío A Estrin
- Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
- Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
| | - Sara E Bari
- Instituto de Química Física de Los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET-Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
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6
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Mozayan E, Rafiee-Pour HA, Ghasemi F. CNT-FET for sensitive hydrogen peroxide biosensing via immobilized Cytochrome c. Arch Biochem Biophys 2023:109695. [PMID: 37479051 DOI: 10.1016/j.abb.2023.109695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 07/16/2023] [Accepted: 07/19/2023] [Indexed: 07/23/2023]
Abstract
H2O2 is an effective substance in the body which contributes to gene expression, insulin metabolism and determining cell shapes. However, a high concentration of H2O2 is harmful to the body and can cause various diseases such as colitis wounds, sepsis disease, lymphocyte proliferation and macrophage apoptosis in systemic lupus erythematosus. In this study, a Cyt c/cMWCNTs/FET was designed to real-time detect H2O2 via immobilized Cyt c on the cMWCNTs/FET surface. The performance of the Cyt c/cMWCNTs/FET biosensor was studied under various parameters such as cMWCNTs and Cyt c concentrations, as well as different pH values. When H2O2 was added to the reaction chamber of the Cyt c/cMWCNTs/FET, the output current of the Bio-FET was reduced, which was attributed to H2O2 detection. The linear response range of this Cyt c/cMWCNT/FET was 10.0 fM to 1.0 nM. The limit of detection and response time of this platform were determined to be 9.13 fM and around 1.0 s, respectively. Also, the operation of the Cyt c/cMWCNTs/FET in the presence of glucose, leucine, tyrosine and ascorbic acid as interfering substances was selective towards H2O2.
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Affiliation(s)
- Elaheh Mozayan
- Department of Cell and Molecular Biology, Faculty of Chemistry, University of Kashan, Kashan, Iran
| | - Hossain-Ali Rafiee-Pour
- Department of Cell and Molecular Biology, Faculty of Chemistry, University of Kashan, Kashan, Iran.
| | - Foad Ghasemi
- Nanoscale Physics Device Lab (NPDL), Department of Physics, University of Kurdistan, Sanandaj, Iran
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7
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Nolan K, Wang Y. Combined spectroscopic and structural approaches to explore the mechanism of histidine-ligated heme-dependent aromatic oxygenases. Methods Enzymol 2023; 685:405-432. [PMID: 37245909 PMCID: PMC11057917 DOI: 10.1016/bs.mie.2023.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The emergence of histidine-ligated heme-dependent aromatic oxygenases (HDAOs) has greatly enriched heme chemistry, and more studies are required to appreciate the diversity found in His-ligated heme proteins. This chapter describes recent methods in probing the HDAO mechanisms in detail, along with the discussion on how they can benefit structure-function studies of other heme systems. The experimental details are centered on studies of TyrHs, followed by explanation of how the results obtained would advance the understanding of the specific enzyme and also HDAOs. Spectroscopic methods, namely, electronic absorption and EPR spectroscopies, and X-ray crystallography are valuable techniques commonly used to characterize the properties of the heme center and the nature of heme-based intermediate. Herein, we show that the combination of these tools are extremely powerful, not only because one can acquire electronic, magnetic, and conformational information from different phases, but also because of the advantages brought by spectroscopic characterization on crystal samples.
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Affiliation(s)
- Katie Nolan
- Department of Chemistry, University of Georgia, Athens, GA, United States
| | - Yifan Wang
- Department of Chemistry, University of Georgia, Athens, GA, United States.
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8
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GLB-3: A resilient, cysteine-rich, membrane-tethered globin expressed in the reproductive and nervous system of Caenorhabditis elegans. J Inorg Biochem 2023; 238:112063. [PMID: 36370505 DOI: 10.1016/j.jinorgbio.2022.112063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/31/2022] [Accepted: 10/31/2022] [Indexed: 11/05/2022]
Abstract
The popular genetic model organism Caenorhabditis elegans (C. elegans) encodes 34 globins, whereby the few that are well-characterized show divergent properties besides the typical oxygen carrier function. Here, we present a biophysical characterization and expression analysis of C. elegans globin-3 (GLB-3). GLB-3 is predicted to exist in two isoforms and is expressed in the reproductive and nervous system. Knockout of this globin causes a 99% reduction in fertility and reduced motility. Spectroscopic analysis reveals that GLB-3 exists as a bis-histidyl-ligated low-spin form in both the ferrous and ferric heme form. A function in binding of diatomic gases is excluded on the basis of the slow CO-binding kinetics. Unlike other globins, GLB-3 is also not capable of reacting with H2O2, H2S, and nitrite. Intriguingly, not only does GLB-3 contain a high number of cysteine residues, it is also highly stable under harsh conditions (pH = 2 and high concentrations of H2O2). The resilience diminishes when the N- and C-terminal extensions are removed. Redox potentiometric measurements reveal a slightly positive redox potential (+8 ± 19 mV vs. SHE), suggesting that the heme iron may be able to oxidize cysteines. Electron paramagnetic resonance shows that formation of an intramolecular disulphide bridge, involving Cys70, affects the heme-pocket region. The results suggest an involvement of the globin in (cysteine) redox chemistry.
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9
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Schweitzer-Stenner R. Heme-Protein Interactions and Functional Relevant Heme Deformations: The Cytochrome c Case. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27248751. [PMID: 36557884 PMCID: PMC9781506 DOI: 10.3390/molecules27248751] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/28/2022] [Accepted: 11/29/2022] [Indexed: 12/14/2022]
Abstract
Heme proteins are known to perform a plethora of biologically important functions. This article reviews work that has been conducted on various class I cytochrome c proteins over a period of nearly 50 years. The article focuses on the relevance of symmetry-lowering heme-protein interactions that affect the function of the electron transfer protein cytochrome c. The article provides an overview of various, mostly spectroscopic studies that explored the electronic structure of the heme group in these proteins and how it is affected by symmetry-lowering deformations. In addition to discussing a large variety of spectroscopic studies, the article provides a theoretical framework that should enable a comprehensive understanding of the physical chemistry that underlies the function not only of cytochrome c but of all heme proteins.
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10
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Guberman-Pfeffer MJ. Assessing Thermal Response of Redox Conduction for Anti-Arrhenius Kinetics in a Microbial Cytochrome Nanowire. J Phys Chem B 2022; 126:10083-10097. [PMID: 36417757 PMCID: PMC9743091 DOI: 10.1021/acs.jpcb.2c06822] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A micrometers-long helical homopolymer of the outer-membrane cytochrome type S (OmcS) from Geobacter sulfurreducens is proposed to transport electrons to extracellular acceptors in an ancient respiratory strategy of biogeochemical and technological significance. OmcS surprisingly exhibits higher conductivity upon cooling (anti-Arrhenius kinetics), an effect previously attributed to H-bond restructuring and heme redox potential shifts. Herein, the temperature sensitivity of redox conductivity is more thoroughly examined with conventional and constant-redox and -pH molecular dynamics and quantum mechanics/molecular mechanics. A 30 K drop in temperature constituted a weak perturbation to electron transfer energetics, changing electronic couplings (⟨Hmn⟩), reaction free energies (ΔGmn), reorganization energies (λmn), and activation energies (Ea) by at most |0.002|, |0.050|, |0.120|, and |0.045| eV, respectively. Changes in ΔGmn reflected -0.07 ± 0.03 V shifts in redox potentials that were caused in roughly equal measure by altered electrostatic interactions with the solvent and protein. Changes in intraprotein H-bonding reproduced the earlier observations. Single-particle diffusion and multiparticle steady-state flux models, parametrized with Marcus theory rates, showed that biologically relevant incoherent hopping cannot qualitatively or quantitatively describe electrical conductivity measured by atomic force microscopy in filamentous OmcS. The discrepancy is attributed to differences between solution-phase simulations and solid-state measurements and the need to model intra- and intermolecular vibrations explicitly.
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Affiliation(s)
- Matthew J. Guberman-Pfeffer
- Department
of Molecular Biophysics and Biochemistry, Yale University, 333 Cedar St., New Haven, Connecticut06510, United States,Microbial
Sciences Institute, Yale University, 840 West Campus Drive, West Haven, Connecticut06516, United States,
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11
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Zheng Y, Deng W, Liu D, Li Y, Peng K, Lorimer GH, Wang J. Redox and spectroscopic properties of mammalian nitrite reductase-like hemoproteins. J Inorg Biochem 2022; 237:111982. [PMID: 36116154 DOI: 10.1016/j.jinorgbio.2022.111982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 01/18/2023]
Abstract
Besides the canonical pathway of L-arginine oxidation to produce nitric oxide (NO) in vivo, the nitrate-nitrite-NO pathway has been widely accepted as another source for circulating NO in mammals, especially under hypoxia. To date, there have been at least ten heme-containing nitrite reductase-like proteins discovered in mammals with activities mainly identified in vitro, including four globins (hemoglobin, myoglobin, neuroglobin (Ngb), cytoglobin (Cygb)), three mitochondrial respiratory chain enzymes (cytochrome c oxidase, cytochrome bc1, cytochrome c), and three other heme proteins (endothelial nitric oxide synthase, cytochrome P450 and indoleamine 2,3-dioxygenase 1 (IDO1)). The pathophysiological functions of these proteins are closely related to their redox and spectroscopic properties, as well as their protein structure, although the physiological roles of Ngb, Cygb and IDO1 remain unclear. So far, comprehensive summaries of the redox and spectroscopic properties of these nitrite reductase-like hemoproteins are still lacking. In this review, we have mainly summarized the published data on the application of ultraviolet-visible, electron paramagnetic resonance, circular dichroism and resonance Raman spectroscopies, and X-ray crystallography in studying nitrite reductase-like activity of these 10 proteins, in order to sort out the relationships among enzymatic function, structure and spectroscopic characterization, which might help in understanding their roles in redox biology and medicine.
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Affiliation(s)
- Yunlong Zheng
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | - Wenwen Deng
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | - Di Liu
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | - Youheng Li
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | - Kang Peng
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | | | - Jun Wang
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China.
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12
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Phosphorylation disrupts long-distance electron transport in cytochrome c. Nat Commun 2022; 13:7100. [PMID: 36402842 PMCID: PMC9675734 DOI: 10.1038/s41467-022-34809-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 11/08/2022] [Indexed: 11/21/2022] Open
Abstract
It has been recently shown that electron transfer between mitochondrial cytochrome c and the cytochrome c1 subunit of the cytochrome bc1 can proceed at long-distance through the aqueous solution. Cytochrome c is thought to adjust its activity by changing the affinity for its partners via Tyr48 phosphorylation, but it is unknown how it impacts the nanoscopic environment, interaction forces, and long-range electron transfer. Here, we constrain the orientation and separation between cytochrome c1 and cytochrome c or the phosphomimetic Y48pCMF cytochrome c, and deploy an array of single-molecule, bulk, and computational methods to investigate the molecular mechanism of electron transfer regulation by cytochrome c phosphorylation. We demonstrate that phosphorylation impairs long-range electron transfer, shortens the long-distance charge conduit between the partners, strengthens their interaction, and departs it from equilibrium. These results unveil a nanoscopic view of the interaction between redox protein partners in electron transport chains and its mechanisms of regulation.
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13
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Di Rocco G, Ranieri A, Borsari M, Sola M, Bortolotti CA, Battistuzzi G. Assessing the Functional and Structural Stability of the Met80Ala Mutant of Cytochrome c in Dimethylsulfoxide. Molecules 2022; 27:molecules27175630. [PMID: 36080396 PMCID: PMC9458088 DOI: 10.3390/molecules27175630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/24/2022] [Accepted: 08/26/2022] [Indexed: 12/02/2022] Open
Abstract
The Met80Ala variant of yeast cytochrome c is known to possess electrocatalytic properties that are absent in the wild type form and that make it a promising candidate for biocatalysis and biosensing. The versatility of an enzyme is enhanced by the stability in mixed aqueous/organic solvents that would allow poorly water-soluble substrates to be targeted. In this work, we have evaluated the effect of dimethylsulfoxide (DMSO) on the functionality of the Met80Ala cytochrome c mutant, by investigating the thermodynamics and kinetics of electron transfer in mixed water/DMSO solutions up to 50% DMSO v/v. In parallel, we have monitored spectroscopically the retention of the main structural features in the same medium, focusing on both the overall protein structure and the heme center. We found that the organic solvent exerts only minor effects on the redox and structural properties of the mutant mostly as a result of the modification of the dielectric constant of the solvent. This would warrant proper functionality of this variant also under these potentially hostile experimental conditions, that differ from the physiological milieu of cytochrome c.
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Affiliation(s)
- Giulia Di Rocco
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - Antonio Ranieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - Marco Borsari
- Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - Marco Sola
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy
| | - Carlo Augusto Bortolotti
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy
- Correspondence: (C.A.B.); (G.B.); Tel.: +39-0592058608 (C.A.B.); +39-059208639 (G.B.)
| | - Gianantonio Battistuzzi
- Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy
- Correspondence: (C.A.B.); (G.B.); Tel.: +39-0592058608 (C.A.B.); +39-059208639 (G.B.)
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14
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Xie H, Song L, Katz S, Zhu J, Liu Y, Tang J, Cai L, Hildebrandt P, Han XX. Electron transfer between cytochrome c and microsomal monooxygenase generates reactive oxygen species that accelerates apoptosis. Redox Biol 2022; 53:102340. [PMID: 35609401 PMCID: PMC9130584 DOI: 10.1016/j.redox.2022.102340] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/13/2022] [Accepted: 05/13/2022] [Indexed: 11/20/2022] Open
Abstract
Generation of reactive oxygen species (ROS) are possibly induced by the crosstalk between mitochondria and endoplasmic reticula, which is physiologically important in apoptosis. Cytochrome c (Cyt c) is believed to play a crucial role in such signaling pathway by interrupting the coupling within microsomal monooxygenase (MMO). In this study, the correlation of ROS production with the electron transfer between Cyt c and the MMO system is investigated by resonance Raman (RR) spectroscopy. Binding of Cyt c to MMO is found to induce the production of ROS, which is quantitatively determined by the in-situ RR spectroscopy reflecting the interactions of Cyt c with generated ROS. The amount of ROS that is produced from isolated endoplasmic reticulum depends on the redox state of the Cyt c, indicating the important role of oxidized Cyt c in accelerating apoptosis. The role of electron transfer from MMO to Cyt c in the apoptotic mitochondria-endoplasmic reticulum pathway is accordingly proposed. This study is of significance for a deeper understanding of how Cyt c regulates apoptotic pathways through the endoplasmic reticulum, and thus may provide a rational basis for the design of antitumor drugs for cancer therapy.
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Affiliation(s)
- Han Xie
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, PR China
| | - Li Song
- National Engineering Laboratory for AIDS Vaccine, School of Life Science, Jilin University, Changchun, 130012, PR China
| | - Sagie Katz
- Department of Chemistry, Technische Universität Berlin, 10623, Berlin, Germany
| | - Jinyu Zhu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, PR China
| | - Yawen Liu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, PR China
| | - Jinping Tang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, PR China
| | - Linjun Cai
- National Engineering Laboratory for AIDS Vaccine, School of Life Science, Jilin University, Changchun, 130012, PR China
| | - Peter Hildebrandt
- Department of Chemistry, Technische Universität Berlin, 10623, Berlin, Germany.
| | - Xiao Xia Han
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, PR China.
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15
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Haslem L, Hays JM, Hays FA. p66Shc in Cardiovascular Pathology. Cells 2022; 11:cells11111855. [PMID: 35681549 PMCID: PMC9180016 DOI: 10.3390/cells11111855] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/30/2022] [Accepted: 06/01/2022] [Indexed: 02/06/2023] Open
Abstract
p66Shc is a widely expressed protein that governs a variety of cardiovascular pathologies by generating, and exacerbating, pro-apoptotic ROS signals. Here, we review p66Shc’s connections to reactive oxygen species, expression, localization, and discuss p66Shc signaling and mitochondrial functions. Emphasis is placed on recent p66Shc mitochondrial function discoveries including structure/function relationships, ROS identity and regulation, mechanistic insights, and how p66Shc-cyt c interactions can influence p66Shc mitochondrial function. Based on recent findings, a new p66Shc mitochondrial function model is also put forth wherein p66Shc acts as a rheostat that can promote or antagonize apoptosis. A discussion of how the revised p66Shc model fits previous findings in p66Shc-mediated cardiovascular pathology follows.
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Affiliation(s)
- Landon Haslem
- Biochemistry and Molecular Biology Department, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (L.H.); (J.M.H.)
| | - Jennifer M. Hays
- Biochemistry and Molecular Biology Department, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (L.H.); (J.M.H.)
| | - Franklin A. Hays
- Biochemistry and Molecular Biology Department, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; (L.H.); (J.M.H.)
- Stephenson Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Correspondence:
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16
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From iron to bacterial electroconductive filaments: Exploring cytochrome diversity using Geobacter bacteria. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2021.214284] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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17
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Zhong F, Alden SL, Hughes RP, Pletneva EV. Comparing Properties of Common Bioinorganic Ligands with Switchable Variants of Cytochrome c. Inorg Chem 2021; 61:1207-1227. [PMID: 34699724 DOI: 10.1021/acs.inorgchem.1c02322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ligand substitution at the metal center is common in catalysis and signal transduction of metalloproteins. Understanding the effects of particular ligands, as well as the polypeptide surrounding, is critical for uncovering mechanisms of these biological processes and exploiting them in the design of bioinspired catalysts and molecular devices. A series of switchable K79G/M80X/F82C (X = Met, His, or Lys) variants of cytochrome (cyt) c was employed to directly compare the stability of differently ligated proteins and activation barriers for Met, His, and Lys replacement at the ferric heme iron. Studies of these variants and their nonswitchable counterparts K79G/M80X have revealed stability trends Met < Lys < His and Lys < His < Met for the protein FeIII-X and FeII-X species, respectively. The differences in the hydrogen-bonding interactions in folded proteins and in solvation of unbound X in the unfolded proteins explain these trends. Calculations of free energy of ligand dissociation in small heme model complexes reveal that the ease of the FeIII-X bond breaking increases in the series amine < imidazole < thioether, mirroring trends in hardness of these ligands. Experimental rate constants for X dissociation in differently ligated cyt c variants are consistent with this sequence, but the differences between Met and His dissociation rates are attenuated because the former process is limited by the heme crevice opening. Analyses of activation parameters and comparisons to those for the Lys-to-Met ligand switch in the alkaline transition suggest that ligand dissociation is entropically driven in all the variants and accompanied by Lys protonation at neutral pH. The described thiolate redox-linked switches have offered a wealth of new information about interactions of different protein-derived ligands with the heme iron in cyt c model proteins, and we anticipate that the strategy of employing these switches could benefit studies of other redox metalloproteins and model complexes.
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Affiliation(s)
- Fangfang Zhong
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - Stephanie L Alden
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - Russell P Hughes
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - Ekaterina V Pletneva
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
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18
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Di Rocco G, Battistuzzi G, Borsari M, Bortolotti CA, Ranieri A, Sola M. The enthalpic and entropic terms of the reduction potential of metalloproteins: Determinants and interplay. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214071] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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19
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How to Turn an Electron Transfer Protein into a Redox Enzyme for Biosensing. Molecules 2021; 26:molecules26164950. [PMID: 34443538 PMCID: PMC8398203 DOI: 10.3390/molecules26164950] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/10/2021] [Accepted: 08/13/2021] [Indexed: 01/10/2023] Open
Abstract
Cytochrome c is a small globular protein whose main physiological role is to shuttle electrons within the mitochondrial electron transport chain. This protein has been widely investigated, especially as a paradigmatic system for understanding the fundamental aspects of biological electron transfer and protein folding. Nevertheless, cytochrome c can also be endowed with a non-native catalytic activity and be immobilized on an electrode surface for the development of third generation biosensors. Here, an overview is offered of the most significant examples of such a functional transformation, carried out by either point mutation(s) or controlled unfolding. The latter can be induced chemically or upon protein immobilization on hydrophobic self-assembled monolayers. We critically discuss the potential held by these systems as core constituents of amperometric biosensors, along with the issues that need to be addressed to optimize their applicability and response.
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20
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Hydrogen bonding rearrangement by a mitochondrial disease mutation in cytochrome bc 1 perturbs heme b H redox potential and spin state. Proc Natl Acad Sci U S A 2021; 118:2026169118. [PMID: 34389670 PMCID: PMC8379992 DOI: 10.1073/pnas.2026169118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
To perform their specific electron-transfer relay functions, hemes commonly adopt low spin states with fine-tuned redox potentials. Understanding molecular elements controlling these properties is crucial for the description of natural proteins and engineering redox-active systems. We describe unusual effects of mitochondrial disease-related mutation in cytochrome bc1, based on which we identify a dual role of hydrogen bonding to the propionate group of heme bH. We observe that stabilization of the hydrogen bond in mutant enhances the redox potential but destabilizes the low spin state of oxidized heme. This demonstrates a critical role of the hydrogen bonding, and heme-protein interactions in general, to secure a suitable redox potential and spin state, a notion that might be universal for other heme proteins. Hemes are common elements of biological redox cofactor chains involved in rapid electron transfer. While the redox properties of hemes and the stability of the spin state are recognized as key determinants of their function, understanding the molecular basis of control of these properties is challenging. Here, benefiting from the effects of one mitochondrial disease–related point mutation in cytochrome b, we identify a dual role of hydrogen bonding (H-bond) to the propionate group of heme bH of cytochrome bc1, a common component of energy-conserving systems. We found that replacing conserved glycine with serine in the vicinity of heme bH caused stabilization of this bond, which not only increased the redox potential of the heme but also induced structural and energetic changes in interactions between Fe ion and axial histidine ligands. The latter led to a reversible spin conversion of the oxidized Fe from 1/2 to 5/2, an effect that potentially reduces the electron transfer rate between the heme and its redox partners. We thus propose that H-bond to the propionate group and heme-protein packing contribute to the fine-tuning of the redox potential of heme and maintaining its proper spin state. A subtle balance is needed between these two contributions: While increasing the H-bond stability raises the heme potential, the extent of increase must be limited to maintain the low spin and diamagnetic form of heme. This principle might apply to other native heme proteins and can be exploited in engineering of artificial heme-containing protein maquettes.
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21
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Karnaukh EA, Bravaya KB. The redox potential of a heme cofactor in Nitrosomonas europaea cytochrome c peroxidase: a polarizable QM/MM study. Phys Chem Chem Phys 2021; 23:16506-16515. [PMID: 34017969 PMCID: PMC11178132 DOI: 10.1039/d0cp06632j] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Redox reactions are crucial to biological processes that protect organisms against oxidative stress. Metalloenzymes, such as peroxidases which reduce excess reactive oxygen species into water, play a key role in detoxification mechanisms. Here we present the results of a polarizable QM/MM study of the reduction potential of the electron transfer heme in the cytochrome c peroxidase of Nitrosomonas europaea. We have found that environment polarization does not substantially affect the computed value of the redox potential. Particular attention has been given to analyzing the role of electrostatic interactions within the protein environment and the solvent on tuning the redox potential of the heme co-factor. We have found that the electrostatic interactions predominantly explain the fluctuations of the vertical ionization/attachment energies of the heme for the sampled configurations, and that the long range electrostatic interactions (up to 40 Å) contribute substantially to the absolute values of the vertical energy gaps.
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22
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SUZUKI Y, SOWA K, KITAZUMI Y, SHIRAI O. The Redox Potential Measurements for Heme Moieties in Variants of D-Fructose Dehydrogenase Based on Mediator-assisted Potentiometric Titration. ELECTROCHEMISTRY 2021. [DOI: 10.5796/electrochemistry.21-00044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Yohei SUZUKI
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Keisei SOWA
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Yuki KITAZUMI
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Osamu SHIRAI
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
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23
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Di Rocco G, Bighi B, Borsari M, Bortolotti CA, Ranieri A, Sola M, Battistuzzi G. Electron Transfer and Electrocatalytic Properties of the Immobilized Met80Ala Cytochrome
c
Variant in Dimethylsulfoxide. ChemElectroChem 2021. [DOI: 10.1002/celc.202100499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Giulia Di Rocco
- Department of Life Sciences University of Modena and Reggio Emilia via Campi 103 41125 Modena Italy
| | - Beatrice Bighi
- Department of Chemistry and Geology University of Modena and Reggio Emilia via Campi 103 41125 Modena Italy
| | - Marco Borsari
- Department of Chemistry and Geology University of Modena and Reggio Emilia via Campi 103 41125 Modena Italy
| | - Carlo Augusto Bortolotti
- Department of Life Sciences University of Modena and Reggio Emilia via Campi 103 41125 Modena Italy
| | - Antonio Ranieri
- Department of Life Sciences University of Modena and Reggio Emilia via Campi 103 41125 Modena Italy
| | - Marco Sola
- Department of Life Sciences University of Modena and Reggio Emilia via Campi 103 41125 Modena Italy
| | - Gianantonio Battistuzzi
- Department of Chemistry and Geology University of Modena and Reggio Emilia via Campi 103 41125 Modena Italy
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24
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Gideon DA, Nirusimhan V, E JC, Sudarsha K, Manoj KM. Mechanism of electron transfers mediated by cytochromes c and b5 in mitochondria and endoplasmic reticulum: classical and murburn perspectives. J Biomol Struct Dyn 2021; 40:9235-9252. [PMID: 33998974 DOI: 10.1080/07391102.2021.1925154] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We explore the mechanism of electron transfers mediated by cytochrome c, a soluble protein involved in mitochondrial oxidative phosphorylation and cytochrome b5, a microsomal membrane protein acting as a redox aide in xenobiotic metabolism. We found minimal conservation in the sequence and surface amino acid residues of cytochrome c/b5 proteins among divergent species. Therefore, we question the evolutionary logic for electron transfer (ET) occurring through affinity binding via recognition of specific surface residues/topography. Also, analysis of putative protein-protein interactions in the crystal structures of these proteins and their redox partners did not point to any specific interaction logic. A comparison of the kinetic and thermodynamic constants of wildtype vs. mutants did not provide strong evidence to support the binding-based ET paradigm, but indicated support for diffusible reactive species (DRS)-mediated process. Topographically divergent cytochromes from one species have been substituted for reaction with proteins from other species, implying the involvement of non-specific interactions. We provide a viable alternative (murburn concept) to classical protein-protein binding-based long range ET mechanism. To account for the promiscuity of interactions and solvent-accessible hemes, we propose that the two proteins act as non- specific redox capacitors, mediating one-electron redox equilibriums involving DRS and unbound ions.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Daniel Andrew Gideon
- Satyamjayatu: The Science & Ethics Foundation, Palakkad District, Kerala State, India.,Department of Biotechnology and Bioinformatics, Bishop Heber College (Autonomous), Tiruchirappalli, Tamil Nadu, India
| | - Vijay Nirusimhan
- Department of Biotechnology and Bioinformatics, Bishop Heber College (Autonomous), Tiruchirappalli, Tamil Nadu, India
| | - Jesu Castin E
- Department of Biotechnology and Bioinformatics, Bishop Heber College (Autonomous), Tiruchirappalli, Tamil Nadu, India
| | - Karthik Sudarsha
- Department of Biotechnology and Bioinformatics, Bishop Heber College (Autonomous), Tiruchirappalli, Tamil Nadu, India
| | - Kelath Murali Manoj
- Satyamjayatu: The Science & Ethics Foundation, Palakkad District, Kerala State, India
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25
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Fenati RA, Sherrell PC, Khodakov DA, Shapter JG, Ellis AV. Spatially isolated redox processes enabled by ambipolar charge transport in multi-walled carbon nanotube mats. MATERIALS HORIZONS 2021; 8:1304-1313. [PMID: 34821923 DOI: 10.1039/d0mh01967d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
This work demonstrates a simple dual-well device which enables spatially isolated solutions to undergo complementary redox reactions. The device functions by the ambipolar transport of charge carriers between two spatially isolated poly(dimethylsiloxane) (PDMS) microwells through an underlying multi-walled carbon nanotube (MWCNT) mat. This MWCNT mat enables charge carriers, produced from the decomposition of an analyte in one solution, to drive a redox reaction in a spatially isolated second colorimetric read-out solution via a potential difference between the wells. As proof-of-concept a visible colorimetric read-out was shown using an enzyme, cytochrome c (reduced in 16 h), and the visualizing reagent 3,3',5,5'-tetramethylbenzidine (TMB) (oxidized in 2.5 h) for the detection of dithionite and hydrogen peroxide, respectively, without any external energy input. We discuss the origin of this phenomenon and highlight the ability of MWCNTs to accept and transport both electrons and holes efficiently between spatially isolated solutions giving rise to a highly versatile sensor suitable for use in simple, low-cost point-of-care diagnostics.
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Affiliation(s)
- Renzo A Fenati
- Department of Chemical Engineering, The University of Melbourne, Parkville, 3010, Victoria, Australia.
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26
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Cheng C, Hayashi S. Ab Initio Evaluation of the Redox Potential of Cytochrome c. J Chem Theory Comput 2021; 17:1194-1207. [PMID: 33459006 DOI: 10.1021/acs.jctc.0c00889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Various biochemical activities of metabolism and biosynthesis are fulfilled by redox processes with explicit electron exchange, which furnish redox enzymes with high chemical reactivity. However, theoretical investigation of a redox process, which simultaneously involves a complex electronic change at a redox metal center and conformational reorganization of the surrounding protein environment coupled to the electronic change, requires computationally conflicting approaches, highly accurate quantum chemical calculations, and long-time molecular dynamics (MD) simulations, limiting the physicochemical understanding of biological redox processes. Here, we theoretically examined a redox process of cytochrome c by means of a hybrid molecular simulation technique, which enables one to consistently treat the redox center at the ab initio quantum chemistry level of theory and the protein reorganization with long-time MD simulations on the microsecond timescale. The calculations successfully evaluated a large absolute redox potential, 4.34 eV, with errors of only 0.03 to 0.34 eV to the experimental ones without any problem-specific empirical parameters. Through the long-time MD sampling, large and nonlinear reorganization of the protein environment was unveiled and the molecular determinants for the redox potential were identified. The present ab initio approach significantly expands the applicability of theoretical investigation to biological redox systems with more electronically complicated redox centers such as polynuclear transition metal complexes.
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Affiliation(s)
- Cheng Cheng
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Shigehiko Hayashi
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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27
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Márquez I, Olloqui-Sariego JL, Molero M, Andreu R, Roldán E, Calvente JJ. Active Role of the Buffer in the Proton-Coupled Electron Transfer of Immobilized Iron Porphyrins. Inorg Chem 2021; 60:42-54. [PMID: 32568550 DOI: 10.1021/acs.inorgchem.0c01091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Evaluation of the proton-coupled electron transfer thermodynamics of immobilized hemin is challenging due to the disparity of its electrochemical titration curves reported in the literature. Deviations from the one-electron, one-proton transfer at circumneutral pHs have been commonly ascribed to either the formation of dimeric species or the ionization of a second iron-bound water molecule. Herein, however, we report on non-idealities in the more acidic region, whose onset and extent vary with the nature and concentration of the commonly used phosphate and acetate buffers. It is shown that these deviations originate in the ligand-exchange binding between the oxidized aquo-hemin complex and the anionic components of the buffer, so that they are restricted to the pH interval where these forms coexist. A stepwise approach was developed to quantify unambiguously the apparent and intrinsic binding equilibrium constants. The apparent binding equilibrium constant exhibits a peak-shaped pH dependence, whose maximum is located at approximately the midpoint between the pKa of the iron-bound water and the first pKa of the buffer, and its magnitude is greater for the phosphate than for the acetate buffer. But strikingly, the opposite trend was found for the magnitude of the intrinsic binding equilibrium constants determined from the apparent ones, due to the different relative locations of the phosphoric and acetic pKa values with respect to that of the oxidized aquo-hemin. To probe the role of the heme propionic residues, a similar study was carried out with a propionic-free iron porphyrin containing eight ethyl residues. These substituents decrease the acidity of the iron-bound water, strengthen the iron(III)-acetate binding, weaken the iron(III)-dihydrogen phosphate binding, and enable the binding between iron(III) and monohydrogen phosphate, which was hampered in hemin by the presence of the negatively charged propionate residues. Overall, this work provides a more complete speciation of immobilized iron porphyrins under acidic conditions than previously considered, showing the substitutional lability of the aqua ligand in the oxidized state of the iron center and the reluctance of its hydroxyl counterpart to anion exchange. Knowledge of these redox- and pH-dependent bindings with the buffer components is crucial for a rigorous quantification of the proton-coupled electron transfer and the electrocatalytic activity of iron porphyrins.
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Affiliation(s)
- Inmaculada Márquez
- Departamento de Quı́mica Fı́sica, Universidad de Sevilla, C/Profesor Garcı́a Conzález, 1, 41012 Sevilla, Spain
| | - José Luis Olloqui-Sariego
- Departamento de Quı́mica Fı́sica, Universidad de Sevilla, C/Profesor Garcı́a Conzález, 1, 41012 Sevilla, Spain
| | - Miguel Molero
- Departamento de Quı́mica Fı́sica, Universidad de Sevilla, C/Profesor Garcı́a Conzález, 1, 41012 Sevilla, Spain
| | - Rafael Andreu
- Departamento de Quı́mica Fı́sica, Universidad de Sevilla, C/Profesor Garcı́a Conzález, 1, 41012 Sevilla, Spain
| | - Emilio Roldán
- Departamento de Quı́mica Fı́sica, Universidad de Sevilla, C/Profesor Garcı́a Conzález, 1, 41012 Sevilla, Spain
| | - Juan José Calvente
- Departamento de Quı́mica Fı́sica, Universidad de Sevilla, C/Profesor Garcı́a Conzález, 1, 41012 Sevilla, Spain
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Lienemann M. Molecular mechanisms of electron transfer employed by native proteins and biological-inorganic hybrid systems. Comput Struct Biotechnol J 2020; 19:206-213. [PMID: 33425252 PMCID: PMC7772364 DOI: 10.1016/j.csbj.2020.12.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 12/03/2020] [Accepted: 12/05/2020] [Indexed: 11/19/2022] Open
Abstract
Recent advances in enzymatic electrosynthesis of desired chemicals in biological-inorganic hybrid systems has generated interest because it can use renewable energy inputs and employs highly specific catalysts that are active at ambient conditions. However, the development of such innovative processes is currently limited by a deficient understanding of the molecular mechanisms involved in electrode-based electron transfer and biocatalysis. Mechanistic studies of non-electrosynthetic electron transferring proteins have provided a fundamental understanding of the processes that take place during enzymatic electrosynthesis. Thus, they may help explain how redox proteins stringently control the reduction potential of the transferred electron and efficiently transfer it to a specific electron acceptor. The redox sites at which electron donor oxidation and electron acceptor reduction take place are typically located in distant regions of the redox protein complex and are electrically connected by an array of closely spaced cofactors. These groups function as electron relay centers and are shielded from the surrounding environment by the electrically insulating apoporotein. In this matrix, electrons travel via electron tunneling, i.e. hopping between neighboring cofactors, over impressive distances of upto several nanometers and, as in the case of the Shewanella oneidensis Mtr electron conduit, traverse the bacterial cell wall to extracellular electron acceptors such as solid ferrihydrite. Here, the biochemical strategies of protein-based electron transfer are presented in order to provide a basis for future studies on the basis of which a more comprehensive understanding of the structural biology of enzymatic electrosynthesis may be attained.
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Abstract
Bioelectrocatalysis has become one of the most important research fields in electrochemistry and provided a firm base for the application of important technology in various bioelectrochemical devices, such as biosensors, biofuel cells, and biosupercapacitors. The understanding and technology of bioelectrocatalysis have greatly improved with the introduction of nanostructured electrode materials and protein-engineering methods over the last few decades. Recently, the electroenzymatic production of renewable energy resources and useful organic compounds (bioelectrosynthesis) has attracted worldwide attention. In this review, we summarize recent progress in the applications of enzymatic bioelectrocatalysis.
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Lancellotti L, Borsari M, Bellei M, Bonifacio A, Bortolotti CA, Di Rocco G, Ranieri A, Sola M, Battistuzzi G. Urea-induced denaturation of immobilized yeast iso-1 cytochrome c: Role of Met80 and Tyr67 in the thermodynamics of unfolding and promotion of pseudoperoxidase and nitrite reductase activities. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.137237] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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31
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Ji J, Chung Y, Hyun K, Chung KY, Kwon Y. Effect of axial ligand on the performance of hemin based catalysts and their use for fuel cells. J IND ENG CHEM 2020. [DOI: 10.1016/j.jiec.2020.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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32
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Négrerie M. Iron transitions during activation of allosteric heme proteins in cell signaling. Metallomics 2020; 11:868-893. [PMID: 30957812 DOI: 10.1039/c8mt00337h] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Allosteric heme proteins can fulfill a very large number of different functions thanks to the remarkable chemical versatility of heme through the entire living kingdom. Their efficacy resides in the ability of heme to transmit both iron coordination changes and iron redox state changes to the protein structure. Besides the properties of iron, proteins may impose a particular heme geometry leading to distortion, which allows selection or modulation of the electronic properties of heme. This review focusses on the mechanisms of allosteric protein activation triggered by heme coordination changes following diatomic binding to proteins as diverse as the human NO-receptor, cytochromes, NO-transporters and sensors, and a heme-activated potassium channel. It describes at the molecular level the chemical capabilities of heme to achieve very different tasks and emphasizes how the properties of heme are determined by the protein structure. Particularly, this reviews aims at giving an overview of the exquisite adaptability of heme, from bacteria to mammals.
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Affiliation(s)
- Michel Négrerie
- Laboratoire d'Optique et Biosciences, INSERM, CNRS, Ecole Polytechnique, 91120 Palaiseau, France.
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Gebicka L. Redox reactions of heme proteins with flavonoids. J Inorg Biochem 2020; 208:111095. [PMID: 32442763 DOI: 10.1016/j.jinorgbio.2020.111095] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/08/2020] [Accepted: 04/26/2020] [Indexed: 02/06/2023]
Abstract
Proteins containing heme groups perform a variety of important functions in living organisms. The heme groups are involved in catalyzing oxidation/reduction reactions, in electron transfer, and in binding small molecules, like oxygen or nitric oxide. Flavonoids, low molecular weight plant polyphenols, are ubiquitous components of human diet. They are also components of many plant extracts used in herbal medicine as well as of food supplements. Due to their relatively low reduction potential, flavonoids are prone to oxidation. This paper provides a review of redox reactions of various heme proteins, including catalase, some peroxidases, cytochrome P450, cytochrome c, myoglobin, and hemoglobin with flavonoids. Potential biological significance of these reactions is discussed, in particular when flavonoids are delivered to the body at pharmacological doses.
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Affiliation(s)
- Lidia Gebicka
- Faculty of Chemistry, Institute of Applied Radiation Chemistry, Lodz University of Technology (TUL), Lodz, Poland.
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34
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Paradisi A, Bellei M, Paltrinieri L, Bortolotti CA, Di Rocco G, Ranieri A, Borsari M, Sola M, Battistuzzi G. Binding of S. cerevisiae iso-1 cytochrome c and its surface lysine-to-alanine variants to cardiolipin: charge effects and the role of the lipid to protein ratio. J Biol Inorg Chem 2020; 25:467-487. [DOI: 10.1007/s00775-020-01776-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/06/2020] [Indexed: 11/30/2022]
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Huang J, Ferlez BH, Young EJ, Kerfeld CA, Kramer DM, Ducat DC. Functionalization of Bacterial Microcompartment Shell Proteins With Covalently Attached Heme. Front Bioeng Biotechnol 2020; 7:432. [PMID: 31993414 PMCID: PMC6962350 DOI: 10.3389/fbioe.2019.00432] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 12/05/2019] [Indexed: 12/26/2022] Open
Abstract
Heme is a versatile redox cofactor that has considerable potential for synthetic biology and bioelectronic applications. The capacity to functionalize non-heme-binding proteins with covalently bound heme moieties in vivo could expand the variety of bioelectronic materials, particularly if hemes could be attached at defined locations so as to facilitate position-sensitive processes like electron transfer. In this study, we utilized the cytochrome maturation system I to develop a simple approach that enables incorporation of hemes into the backbone of target proteins in vivo. We tested our methodology by targeting the self-assembling bacterial microcompartment shell proteins, and inserting functional hemes at multiple locations in the protein backbone. We found substitution of three amino acids on the target proteins promoted heme attachment with high occupancy. Spectroscopic measurements suggested these modified proteins covalently bind low-spin hemes, with relative low redox midpoint potentials (about -210 mV vs. SHE). Heme-modified shell proteins partially retained their self-assembly properties, including the capacity to hexamerize, and form inter-hexamer attachments. Heme-bound shell proteins demonstrated the capacity to integrate into higher-order shell assemblies, however, the structural features of these macromolecular complexes was sometimes altered. Altogether, we report a versatile strategy for generating electron-conductive cytochromes from structurally-defined proteins, and provide design considerations on how heme incorporation may interface with native assembly properties in engineered proteins.
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Affiliation(s)
- Jingcheng Huang
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, United States
| | - Bryan H. Ferlez
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, United States
| | - Eric J. Young
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, United States
| | - Cheryl A. Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, United States
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - David M. Kramer
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, United States
| | - Daniel C. Ducat
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, United States
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, United States
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36
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Paradisi A, Lancellotti L, Borsari M, Bellei M, Bortolotti CA, Di Rocco G, Ranieri A, Sola M, Battistuzzi G. Met80 and Tyr67 affect the chemical unfolding of yeast cytochrome c: comparing the solution vs.immobilized state. RSC Chem Biol 2020. [DOI: 10.1039/d0cb00115e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The motional regime affects the unfolding propensity and axial heme coordination of the Met80Ala and Met80Ala/Tyr67Ala variants of yeast iso-1 cytochromec.
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Affiliation(s)
| | - Lidia Lancellotti
- Department of Chemistry and Geology
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | - Marco Borsari
- Department of Chemistry and Geology
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | - Marzia Bellei
- Department of Life Sciences
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | | | - Giulia Di Rocco
- Department of Life Sciences
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | - Antonio Ranieri
- Department of Life Sciences
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
| | - Marco Sola
- Department of Life Sciences
- University of Modena and Reggio Emilia
- 41126 Modena
- Italy
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37
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Affiliation(s)
- Kenji KANO
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
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38
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Jenner LP, Kurth JM, van Helmont S, Sokol KP, Reisner E, Dahl C, Bradley JM, Butt JN, Cheesman MR. Heme ligation and redox chemistry in two bacterial thiosulfate dehydrogenase (TsdA) enzymes. J Biol Chem 2019; 294:18002-18014. [PMID: 31467084 PMCID: PMC6879331 DOI: 10.1074/jbc.ra119.010084] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 08/26/2019] [Indexed: 01/04/2023] Open
Abstract
Thiosulfate dehydrogenases (TsdAs) are bidirectional bacterial di-heme enzymes that catalyze the interconversion of tetrathionate and thiosulfate at measurable rates in both directions. In contrast to our knowledge of TsdA activities, information on the redox properties in the absence of substrates is rather scant. To address this deficit, we combined magnetic CD (MCD) spectroscopy and protein film electrochemistry (PFE) in a study to resolve heme ligation and redox chemistry in two representative TsdAs. We examined the TsdAs from Campylobacter jejuni, a microaerobic human pathogen, and from the purple sulfur bacterium Allochromatium vinosum. In these organisms, the enzyme functions as a tetrathionate reductase and a thiosulfate oxidase, respectively. The active site Heme 1 in both enzymes has His/Cys ligation in the ferric and ferrous states and the midpoint potentials (Em) of the corresponding redox transformations are similar, −185 mV versus standard hydrogen electrode (SHE). However, fundamental differences are observed in the properties of the second, electron transferring, Heme 2. In C. jejuni, TsdA Heme 2 has His/Met ligation and an Em of +172 mV. In A. vinosum TsdA, Heme 2 reduction triggers a switch from His/Lys ligation (Em, −129 mV) to His/Met (Em, +266 mV), but the rates of interconversion are such that His/Lys ligation would be retained during turnover. In summary, our findings have unambiguously assigned Em values to defined axial ligand sets in TsdAs, specified the rates of Heme 2 ligand exchange in the A. vinosum enzyme, and provided information relevant to describing their catalytic mechanism(s).
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Affiliation(s)
- Leon P Jenner
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Julia M Kurth
- Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich Wilhelms Universität Bonn, D-53115 Bonn, Germany
| | - Sebastian van Helmont
- Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich Wilhelms Universität Bonn, D-53115 Bonn, Germany
| | - Katarzyna P Sokol
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Erwin Reisner
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Christiane Dahl
- Institut für Mikrobiologie & Biotechnologie, Rheinische Friedrich Wilhelms Universität Bonn, D-53115 Bonn, Germany
| | - Justin M Bradley
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Julea N Butt
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Myles R Cheesman
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
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39
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5,7,3′,4′-Hydroxy substituted flavonoids reduce the heme of cytochrome c with a range of rate constants. Biochimie 2019; 162:167-175. [DOI: 10.1016/j.biochi.2019.04.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 04/25/2019] [Indexed: 12/20/2022]
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40
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Determination of the magnetic properties and orientation of the heme axial ligands of PpcA from Geobacter metallireducens by paramagnetic NMR. J Inorg Biochem 2019; 198:110718. [PMID: 31153111 DOI: 10.1016/j.jinorgbio.2019.110718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/09/2019] [Accepted: 05/13/2019] [Indexed: 11/22/2022]
Abstract
The rising interest in the use of Geobacter bacteria for biotechnological applications demands a deep understanding of how these bacteria are able to thrive in a variety of environments and perform extracellular electron transfer. The Geobacter metallireducens bacterium can couple the oxidation of a wide range of compounds to the reduction of several extracellular acceptors, including heavy metals, toxic organic compounds or electrode surfaces. The periplasmic c-type cytochrome PpcA from this bacterium is a member of a family composed of five periplasmic triheme cytochromes, which are important to bridge the electron transfer between the cytoplasm and the extracellular environment. To better understand the functional mechanism of PpcA it is essential to obtain structural data for this cytochrome. In this work, the geometry of the heme axial ligands, as well as the magnetic properties of the hemes were determined for the oxidized form of the cytochrome, using the 13C NMR chemical shifts of the heme α-substituents. The results were further compared with those previously obtained for the homologous cytochrome from Geobacter sulfurreducens. The orientations of the axial histidine planes and the magnetic properties of the hemes are conserved in both proteins. Overall, the results obtained allowed the definition of the orientation of the magnetic axes of PpcA from G. metallireducens, which will be used as constraints to assist the solution structure determination of the cytochrome in the oxidized form.
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41
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A Density Functional Theory-Based Scheme to Compute the Redox Potential of a Transition Metal Complex: Applications to Heme Compound. Molecules 2019; 24:molecules24040819. [PMID: 30823577 PMCID: PMC6412623 DOI: 10.3390/molecules24040819] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 02/18/2019] [Accepted: 02/21/2019] [Indexed: 12/23/2022] Open
Abstract
We estimated the redox potential of a model heme compound by using the combination of our density functionals with a computational scheme, which corrects the solvation energy to the normal solvent model. Among many density functionals, the LC-BOP12 functional gave the smallest mean absolute error of 0.16 V in the test molecular sets. The application of these methods revealed that the redox potential of a model heme can be controlled within 200 mV by changing the protonation state and even within 20 mV by the flipping of the ligand histidine. In addition, the redox potential depends on the inverse of the dielectric constant, which controls the surroundings. The computational results also imply that a system with a low dielectric constant avoids the charged molecule by controlling either the redox potential or the protonation system.
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42
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HIBINO Y, KAWAI S, KITAZUMI Y, SHIRAI O, KANO K. Protein-Engineering Improvement of Direct Electron Transfer-Type Bioelectrocatalytic Properties of d-Fructose Dehydrogenase. ELECTROCHEMISTRY 2019. [DOI: 10.5796/electrochemistry.18-00068] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Yuya HIBINO
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Shota KAWAI
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Yuki KITAZUMI
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Osamu SHIRAI
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Kenji KANO
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
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43
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Vitvitsky V, Miljkovic JL, Bostelaar T, Adhikari B, Yadav PK, Steiger AK, Torregrossa R, Pluth MD, Whiteman M, Banerjee R, Filipovic MR. Cytochrome c Reduction by H 2S Potentiates Sulfide Signaling. ACS Chem Biol 2018; 13:2300-2307. [PMID: 29966080 PMCID: PMC6450078 DOI: 10.1021/acschembio.8b00463] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydrogen sulfide (H2S) is an endogenously produced gas that is toxic at high concentrations. It is eliminated by a dedicated mitochondrial sulfide oxidation pathway, which connects to the electron transfer chain at the level of complex III. Direct reduction of cytochrome c (Cyt C) by H2S has been reported previously but not characterized. In this study, we demonstrate that reduction of ferric Cyt C by H2S exhibits hysteretic behavior, which suggests the involvement of reactive sulfur species in the reduction process and is consistent with a reaction stoichiometry of 1.5 mol of Cyt C reduced/mol of H2S oxidized. H2S increases O2 consumption by human cells (HT29 and HepG2) treated with the complex III inhibitor antimycin A, which is consistent with the entry of sulfide-derived electrons at the level of complex IV. Cyt C-dependent H2S oxidation stimulated protein persulfidation in vitro, while silencing of Cyt C expression decreased mitochondrial protein persulfidation in a cell culture. Cyt C released during apoptosis was correlated with persulfidation of procaspase 9 and with loss of its activity. These results reveal a potential role for the electron transfer chain in general, and Cyt C in particular, for potentiating sulfide-based signaling.
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Affiliation(s)
- Victor Vitvitsky
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jan Lj. Miljkovic
- Université de Bordeaux, IBGC, UMR 5095, F-33077 Bordeaux, France
- CNRS, IBGC, UMR 5095, F-33077 Bordeaux, France
| | - Trever Bostelaar
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Bikash Adhikari
- Université de Bordeaux, IBGC, UMR 5095, F-33077 Bordeaux, France
- CNRS, IBGC, UMR 5095, F-33077 Bordeaux, France
| | - Pramod K. Yadav
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Andrea K. Steiger
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, and Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | | | - Michael D. Pluth
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, and Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Matthew Whiteman
- University of Exeter Medical School, St. Luke’s Campus, Exeter EX1 2LU, U.K
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Milos R. Filipovic
- Université de Bordeaux, IBGC, UMR 5095, F-33077 Bordeaux, France
- CNRS, IBGC, UMR 5095, F-33077 Bordeaux, France
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44
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Schweitzer-Stenner R. Relating the multi-functionality of cytochrome c to membrane binding and structural conversion. Biophys Rev 2018; 10:1151-1185. [PMID: 29574621 PMCID: PMC6082307 DOI: 10.1007/s12551-018-0409-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 02/23/2018] [Indexed: 12/16/2022] Open
Abstract
Cytochrome c is known as an electron-carrying protein in the respiratory chain of mitochondria. Over the last 20 years, however, alternative functions of this very versatile protein have become the focus of research interests. Upon binding to anionic lipids such as cardiolipin, the protein acquires peroxidase activity. Multiple lines of evidence suggest that this requires a conformational change of the protein which involves partial unfolding of its tertiary structure. This review summarizes the current state of knowledge of how cytochrome c interacts with cardiolipin-containing surfaces and how this affects its structure and function. In this context, we delineate partially conflicting results regarding the affinity of cytochrome c binding to cardiolipin-containing liposomes of different size and its influence on the structure of the protein and the morphology of the membrane.
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45
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Pshenichnyuk SA, Modelli A, Komolov AS. Interconnections between dissociative electron attachment and electron-driven biological processes. INT REV PHYS CHEM 2018. [DOI: 10.1080/0144235x.2018.1461347] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Stanislav A. Pshenichnyuk
- Institute of Molecule and Crystal Physics – Subdivision of the Ufa Research Centre of the Russian Academy of Sciences, Ufa, Russia
| | - Alberto Modelli
- Dipartimento di Chimica ‘G. Ciamician’, Università di Bologna, Bologna, Italy
- Centro Interdipartimentale di Ricerca in Scienze Ambientali, Ravenna, Italy
| | - Alexei S. Komolov
- Department of Solid State Electronics, St. Petersburg State University, St. Petersburg, Russia
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46
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Zhang L, Kepp KP, Ulstrup J, Zhang J. Redox Potentials and Electronic States of Iron Porphyrin IX Adsorbed on Single Crystal Gold Electrode Surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:3610-3618. [PMID: 29510058 DOI: 10.1021/acs.langmuir.8b00163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Metalloporphyrins are active sites in metalloproteins and synthetic catalysts. They have also been studied extensively by electrochemistry as well as being prominent targets in electrochemical scanning tunneling microscopy (STM). Previous studies of FePPIX adsorbed on graphite and alkylthiol modified Au electrodes showed a pair of reversible Fe(III/II)PPIX peaks at about -0.41 V (vs NHE) at high solution pH. We recently used iron protoporphyrin IX (FePPIX) as an intercalating probe for long-range electrochemical electron transfer through a G-quadruplex oligonucleotide (DNAzyme); this study disclosed two, rather than a single pair of voltammetric peaks with a new and dominating peak, shifted 200 mV positive relative to the ≈-0.4 V peak. Prompted by this unexpected observation, we report here a study of the voltammetry of FePPIX itself on single-crystal Au(111), (100), and (110) and polycrystalline Au electrode surfaces. In all cases the dominating pair of new Fe(III/II)PPIX redox peaks, shifted positively by more than 200 mV compared to those of previous studies appeared. This observation is supported by density functional theory (DFT) which shows that strong dispersion forces in the FePPIX/Au electronic interaction drive the midpoint potential toward positive values. The FePPIX spin states depend on interaction with the Au(111) interface, converting all the Fe(II)/(III)PPIX species into low-spin states. These results support electrochemical evidence for the nature of the electronic coupling between FePPIX and Au-surfaces, and the electronic states of adsorbate molecules, with a bearing also on recent reports of magnetic FePPIX/Au(111) interactions in ultrahigh vacuum (UHV).
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Affiliation(s)
- Ling Zhang
- Department of Chemistry , Technical University of Denmark , Building 207, Kemitorvet, DK-2800 Kgs. Lyngby , Denmark
| | - Kasper P Kepp
- Department of Chemistry , Technical University of Denmark , Building 207, Kemitorvet, DK-2800 Kgs. Lyngby , Denmark
| | - Jens Ulstrup
- Department of Chemistry , Technical University of Denmark , Building 207, Kemitorvet, DK-2800 Kgs. Lyngby , Denmark
| | - Jingdong Zhang
- Department of Chemistry , Technical University of Denmark , Building 207, Kemitorvet, DK-2800 Kgs. Lyngby , Denmark
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47
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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]
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48
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Alvarez-Paggi D, Hannibal L, Castro MA, Oviedo-Rouco S, Demicheli V, Tórtora V, Tomasina F, Radi R, Murgida DH. Multifunctional Cytochrome c: Learning New Tricks from an Old Dog. Chem Rev 2017; 117:13382-13460. [DOI: 10.1021/acs.chemrev.7b00257] [Citation(s) in RCA: 135] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Damián Alvarez-Paggi
- Departamento
de Química Inorgánica, Analítica y Química
Física and INQUIMAE (CONICET-UBA), Facultad de Ciencias Exactas
y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, piso 1, Buenos Aires C1428EHA, Argentina
| | - Luciana Hannibal
- Department
of Pediatrics, Universitätsklinikum Freiburg, Mathildenstrasse 1, Freiburg 79106, Germany
- Departamento
de Bioquímica and Center for Free Radical and Biomedical Research,
Facultad de Medicina, Universidad de la República, Av.
Gral. Flores 2125, Montevideo 11800, Uruguay
| | - María A. Castro
- Departamento
de Química Inorgánica, Analítica y Química
Física and INQUIMAE (CONICET-UBA), Facultad de Ciencias Exactas
y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, piso 1, Buenos Aires C1428EHA, Argentina
| | - Santiago Oviedo-Rouco
- Departamento
de Química Inorgánica, Analítica y Química
Física and INQUIMAE (CONICET-UBA), Facultad de Ciencias Exactas
y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, piso 1, Buenos Aires C1428EHA, Argentina
| | - Veronica Demicheli
- Departamento
de Bioquímica and Center for Free Radical and Biomedical Research,
Facultad de Medicina, Universidad de la República, Av.
Gral. Flores 2125, Montevideo 11800, Uruguay
| | - Veronica Tórtora
- Departamento
de Bioquímica and Center for Free Radical and Biomedical Research,
Facultad de Medicina, Universidad de la República, Av.
Gral. Flores 2125, Montevideo 11800, Uruguay
| | - Florencia Tomasina
- Departamento
de Bioquímica and Center for Free Radical and Biomedical Research,
Facultad de Medicina, Universidad de la República, Av.
Gral. Flores 2125, Montevideo 11800, Uruguay
| | - Rafael Radi
- Departamento
de Bioquímica and Center for Free Radical and Biomedical Research,
Facultad de Medicina, Universidad de la República, Av.
Gral. Flores 2125, Montevideo 11800, Uruguay
| | - Daniel H. Murgida
- Departamento
de Química Inorgánica, Analítica y Química
Física and INQUIMAE (CONICET-UBA), Facultad de Ciencias Exactas
y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, piso 1, Buenos Aires C1428EHA, Argentina
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49
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Li L, Chen X, Cai W, Zhang M, Liang X, Tian A. Theoretical research on the charge transport properties of imidazoles axial-coordinated with protoheme molecule. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2017. [DOI: 10.1142/s0219633617500493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The charge transport properties and the stability of imidazoles with axial-coordinated protoheme molecules have been investigated by the density functional theory (DFT) at B3LYP/6-31[Formula: see text]G(d) level. With energy of each compound, we find that all heme Fe[Formula: see text] and Fe[Formula: see text] complex compounds axially coordinate the imidazoles by strong field in low-spin state. Meanwhile, binding energies were calculated, the structure feature and the frontier orbital distribution of complex compounds were also analyzed. On the basis of Marcus theory, the reorganization energy, matrix element and charge transport rate constant were calculated. The results show that the charge transport rate of the complex compound coordinated imidazole is greater than that of the complex compound coordinated 2-methyl imidazole, which indicates that the charge transfer between the imidazole and the heme iron is more favorable to the heme iron than the 2-methyl imidazole. The results are in good agreement with the experimental ones obtained by Battistuzzi.
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Affiliation(s)
- Laicai Li
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066, P. R. China
| | - Xiao Chen
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066, P. R. China
| | - Wanfei Cai
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066, P. R. China
| | - Ming Zhang
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066, P. R. China
| | - Xiaoqin Liang
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066, P. R. China
| | - Anmin Tian
- College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
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50
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Solomon LA, Kronenberg JB, Fry HC. Control of Heme Coordination and Catalytic Activity by Conformational Changes in Peptide-Amphiphile Assemblies. J Am Chem Soc 2017; 139:8497-8507. [PMID: 28505436 DOI: 10.1021/jacs.7b01588] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Self-assembling peptide materials have gained significant attention, due to well-demonstrated applications, but they are functionally underutilized. To advance their utility, we use noncovalent interactions to incorporate the biological cofactor heme-B for catalysis. Heme-proteins achieve differing functions through structural and coordinative variations. Here, we replicate this phenomenon by highlighting changes in heme reactivity as a function of coordination, sequence, and morphology (micelles versus fibers) in a series of simple peptide amphiphiles with the sequence c16-xyL3K3-CO2H where c16 is a palmitoyl moiety and xy represents the heme binding region: AA, AH, HH, and MH. The morphology of this peptide series is characterized using transmission electron and atomic force microscopies as well as dynamic light scattering. Within this small library of peptide constructs, we show that three spectroscopically (UV/visible and electron paramagnetic resonance) distinct heme environments were generated: noncoordinated/embedded high-spin, five-coordinate high-spin, and six-coordinate low-spin. The resulting material's functional dependence on sequence and supramolecular morphology is highlighted 2-fold. First, the heme active site binds carbon monoxide in both micelles and fibers, demonstrating that the heme active site in both morphologies is accessible to small molecules for catalysis. Second, peroxidase activity was observed in heme-containing micelles yet was significantly reduced in heme-containing fibers. We briefly discuss the implications these findings have in the production of functional, self-assembling peptide materials.
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Affiliation(s)
- Lee A Solomon
- Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States
| | - Jacob B Kronenberg
- Illinois Math and Science Academy , 1500 West Sullivan Road, Aurora, Illinois 60506, United States
| | - H Christopher Fry
- Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States
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