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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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Chino M, Di Costanzo LF, Leone L, La Gatta S, Famulari A, Chiesa M, Lombardi A, Pavone V. Designed Rubredoxin miniature in a fully artificial electron chain triggered by visible light. Nat Commun 2023; 14:2368. [PMID: 37185349 PMCID: PMC10130062 DOI: 10.1038/s41467-023-37941-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 04/06/2023] [Indexed: 05/17/2023] Open
Abstract
Designing metal sites into de novo proteins has significantly improved, recently. However, identifying the minimal coordination spheres, able to encompass the necessary information for metal binding and activity, still represents a great challenge, today. Here, we test our understanding with a benchmark, nevertheless difficult, case. We assemble into a miniature 28-residue protein, the quintessential elements required to fold properly around a FeCys4 redox center, and to function efficiently in electron-transfer. This study addresses a challenge in de novo protein design, as it reports the crystal structure of a designed tetra-thiolate metal-binding protein in sub-Å agreement with the intended design. This allows us to well correlate structure to spectroscopic and electrochemical properties. Given its high reduction potential compared to natural and designed FeCys4-containing proteins, we exploit it as terminal electron acceptor of a fully artificial chain triggered by visible light.
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Affiliation(s)
- Marco Chino
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, 80126, Napoli, Italy
| | - Luigi Franklin Di Costanzo
- Department of Agricultural Sciences, University of Naples Federico II, Via Università 100, 80055, Portici, Italy
| | - Linda Leone
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, 80126, Napoli, Italy
| | - Salvatore La Gatta
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, 80126, Napoli, Italy
| | - Antonino Famulari
- Department of Chemistry, University of Torino, Via Giuria 9, 10125, Torino, Italy
- Department of Condensed Matter Physics, University of Zaragoza, Calle Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Mario Chiesa
- Department of Chemistry, University of Torino, Via Giuria 9, 10125, Torino, Italy
| | - Angela Lombardi
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, 80126, Napoli, Italy.
| | - Vincenzo Pavone
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, 80126, Napoli, Italy.
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3
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Turilli-Ghisolfi ES, Lualdi M, Fasano M. Ligand-Based Regulation of Dynamics and Reactivity of Hemoproteins. Biomolecules 2023; 13:683. [PMID: 37189430 PMCID: PMC10135655 DOI: 10.3390/biom13040683] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/14/2023] [Accepted: 04/15/2023] [Indexed: 05/17/2023] Open
Abstract
Hemoproteins include several heme-binding proteins with distinct structure and function. The presence of the heme group confers specific reactivity and spectroscopic properties to hemoproteins. In this review, we provide an overview of five families of hemoproteins in terms of dynamics and reactivity. First, we describe how ligands modulate cooperativity and reactivity in globins, such as myoglobin and hemoglobin. Second, we move on to another family of hemoproteins devoted to electron transport, such as cytochromes. Later, we consider heme-based reactivity in hemopexin, the main heme-scavenging protein. Then, we focus on heme-albumin, a chronosteric hemoprotein with peculiar spectroscopic and enzymatic properties. Eventually, we analyze the reactivity and dynamics of the most recently discovered family of hemoproteins, i.e., nitrobindins.
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Affiliation(s)
| | | | - Mauro Fasano
- Department of Science and High Technology, University of Insubria, 22100 Como, Italy
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4
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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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5
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Chattopadhyay S, Mukherjee M, Kandemir B, Bowman SEJ, Bren KL, Dey A. Contributions to cytochrome c inner- and outer-sphere reorganization energy. Chem Sci 2021; 12:11894-11913. [PMID: 34659730 PMCID: PMC8442690 DOI: 10.1039/d1sc02865k] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 08/05/2021] [Indexed: 11/21/2022] Open
Abstract
Cytochromes c are small water-soluble proteins that catalyze electron transfer in metabolism and energy conversion processes. Hydrogenobacter thermophilus cytochrome c552 presents a curious case in displaying fluxionality of its heme axial methionine ligand; this behavior is altered by single point mutation of the Q64 residue to N64 or V64, which fixes the ligand in a single configuration. The reorganization energy (λ) of these cytochrome c552 variants is experimentally determined using a combination of rotating disc electrochemistry, chronoamperometry and cyclic voltammetry. The differences between the λ determined from these complementary techniques helps to deconvolute the contribution of the active site and its immediate environment to the overall λ (λTotal). The experimentally determined λ values in conjunction with DFT calculations indicate that the differences in λ among the protein variants are mainly due to the differences in contributions from the protein environment and not just inner-sphere λ. DFT calculations indicate that the position of residue 64, responsible for the orientation of the axial methionine, determines the geometric relaxation of the redox active molecular orbital (RAMO). The orientation of the RAMO with respect to the heme is key to determining electron transfer coupling (HAB) which results in higher ET rates in the wild-type protein relative to the Q64V mutant despite a 150 mV higher λTotal in the former. Efficient delocalization of the redox-active molecular orbital (RAMO) in HtWT results in an increase in HAB value which in turn accelerates the electron transfer (ET) rate in spite of the higher reorganization energy (λ) than the HtQ64V mutant.![]()
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Affiliation(s)
- Samir Chattopadhyay
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A Raja SC Mullick Road Kolkata WB 700032 India
| | - Manjistha Mukherjee
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A Raja SC Mullick Road Kolkata WB 700032 India
| | - Banu Kandemir
- Department of Chemistry, University of Rochester Rochester NY 14627-0216 USA
| | - Sarah E J Bowman
- Department of Chemistry, University of Rochester Rochester NY 14627-0216 USA
| | - Kara L Bren
- Department of Chemistry, University of Rochester Rochester NY 14627-0216 USA
| | - Abhishek Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A Raja SC Mullick Road Kolkata WB 700032 India
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6
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7
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Maglio O, Chino M, Vicari C, Pavone V, Louro RO, Lombardi A. Histidine orientation in artificial peroxidase regioisomers as determined by paramagnetic NMR shifts. Chem Commun (Camb) 2021; 57:990-993. [PMID: 33399143 DOI: 10.1039/d0cc06676a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Fe-Mimochrome VI*a is a synthetic peroxidase and peroxygenase, featuring two different peptides that are covalently-linked to deuteroheme. To perform a systematic structure/function correlation, we purposely shortened the distance between the distal peptide and the heme, allowing for the separation and characterization of two regioisomers. They differ in both His axial-ligand orientation, as determined by paramagnetic NMR shifts, and activity. These findings highlight that synthetic metalloenzymes may provide an efficient tool for disentangling the role of axial ligand orientation over peroxidase activity.
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Affiliation(s)
- Ornella Maglio
- Department of Chemical Sciences, University Federico II of Naples, Via Cintia 21, Naples, 80126, Italy. and IBB-CNR, Via Mezzocannone 16, Naples, 80134, Italy
| | - Marco Chino
- Department of Chemical Sciences, University Federico II of Naples, Via Cintia 21, Naples, 80126, Italy.
| | - Claudia Vicari
- Department of Chemical Sciences, University Federico II of Naples, Via Cintia 21, Naples, 80126, Italy.
| | - Vincenzo Pavone
- Department of Chemical Sciences, University Federico II of Naples, Via Cintia 21, Naples, 80126, Italy.
| | - Ricardo O Louro
- ITQB-UNL, Av. da Republica (EAN), Oeiras 2780-157, Portugal.
| | - Angela Lombardi
- Department of Chemical Sciences, University Federico II of Naples, Via Cintia 21, Naples, 80126, Italy.
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8
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Bacellar C, Kinschel D, Mancini GF, Ingle RA, Rouxel J, Cannelli O, Cirelli C, Knopp G, Szlachetko J, Lima FA, Menzi S, Pamfilidis G, Kubicek K, Khakhulin D, Gawelda W, Rodriguez-Fernandez A, Biednov M, Bressler C, Arrell CA, Johnson PJM, Milne CJ, Chergui M. Spin cascade and doming in ferric hemes: Femtosecond X-ray absorption and X-ray emission studies. Proc Natl Acad Sci U S A 2020; 117:21914-21920. [PMID: 32848065 PMCID: PMC7486745 DOI: 10.1073/pnas.2009490117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The structure-function relationship is at the heart of biology, and major protein deformations are correlated to specific functions. For ferrous heme proteins, doming is associated with the respiratory function in hemoglobin and myoglobins. Cytochrome c (Cyt c) has evolved to become an important electron-transfer protein in humans. In its ferrous form, it undergoes ligand release and doming upon photoexcitation, but its ferric form does not release the distal ligand, while the return to the ground state has been attributed to thermal relaxation. Here, by combining femtosecond Fe Kα and Kβ X-ray emission spectroscopy (XES) with Fe K-edge X-ray absorption near-edge structure (XANES), we demonstrate that the photocycle of ferric Cyt c is entirely due to a cascade among excited spin states of the iron ion, causing the ferric heme to undergo doming, which we identify. We also argue that this pattern is common to a wide diversity of ferric heme proteins, raising the question of the biological relevance of doming in such proteins.
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Affiliation(s)
- Camila Bacellar
- Laboratoire de Spectroscopie Ultrarapide, Institut des Sciences et Ingéniéries Chimiques and Lausanne Centre for Ultrafast Science, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Dominik Kinschel
- Laboratoire de Spectroscopie Ultrarapide, Institut des Sciences et Ingéniéries Chimiques and Lausanne Centre for Ultrafast Science, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Giulia F Mancini
- Laboratoire de Spectroscopie Ultrarapide, Institut des Sciences et Ingéniéries Chimiques and Lausanne Centre for Ultrafast Science, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Rebecca A Ingle
- Laboratoire de Spectroscopie Ultrarapide, Institut des Sciences et Ingéniéries Chimiques and Lausanne Centre for Ultrafast Science, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Jérémy Rouxel
- Laboratoire de Spectroscopie Ultrarapide, Institut des Sciences et Ingéniéries Chimiques and Lausanne Centre for Ultrafast Science, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Oliviero Cannelli
- Laboratoire de Spectroscopie Ultrarapide, Institut des Sciences et Ingéniéries Chimiques and Lausanne Centre for Ultrafast Science, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Claudio Cirelli
- Swiss Free Electron Laser, Paul-Scherrer-Institut (PSI), 5232 Villigen PSI, Switzerland
| | - Gregor Knopp
- Swiss Free Electron Laser, Paul-Scherrer-Institut (PSI), 5232 Villigen PSI, Switzerland
| | - Jakub Szlachetko
- Institute of Nuclear Physics, Polish Academy of Sciences, 31-342 Kraków, Poland
| | | | - Samuel Menzi
- Swiss Free Electron Laser, Paul-Scherrer-Institut (PSI), 5232 Villigen PSI, Switzerland
| | - Georgios Pamfilidis
- Swiss Free Electron Laser, Paul-Scherrer-Institut (PSI), 5232 Villigen PSI, Switzerland
| | | | | | - Wojciech Gawelda
- European X-ray Free Electron Laser, D-22869 Schenefeld, Germany
- Faculty of Physics, Adam Mickiewicz University, 61-614 Poznan, Poland
| | | | - Mykola Biednov
- European X-ray Free Electron Laser, D-22869 Schenefeld, Germany
| | | | - Christopher A Arrell
- Swiss Free Electron Laser, Paul-Scherrer-Institut (PSI), 5232 Villigen PSI, Switzerland
| | - Philip J M Johnson
- Swiss Free Electron Laser, Paul-Scherrer-Institut (PSI), 5232 Villigen PSI, Switzerland
| | - Christopher J Milne
- Swiss Free Electron Laser, Paul-Scherrer-Institut (PSI), 5232 Villigen PSI, Switzerland
| | - Majed Chergui
- Laboratoire de Spectroscopie Ultrarapide, Institut des Sciences et Ingéniéries Chimiques and Lausanne Centre for Ultrafast Science, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland;
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9
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Leone L, Chino M, Nastri F, Maglio O, Pavone V, Lombardi A. Mimochrome, a metalloporphyrin‐based catalytic Swiss knife†. Biotechnol Appl Biochem 2020; 67:495-515. [DOI: 10.1002/bab.1985] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 07/09/2020] [Indexed: 12/20/2022]
Affiliation(s)
- Linda Leone
- Department of Chemical Sciences University of Napoli “Federico II” Napoli Italy
| | - Marco Chino
- Department of Chemical Sciences University of Napoli “Federico II” Napoli Italy
| | - Flavia Nastri
- Department of Chemical Sciences University of Napoli “Federico II” Napoli Italy
| | - Ornella Maglio
- Department of Chemical Sciences University of Napoli “Federico II” Napoli Italy
- IBB ‐ National Research Council Napoli Italy
| | - Vincenzo Pavone
- Department of Chemical Sciences University of Napoli “Federico II” Napoli Italy
| | - Angela Lombardi
- Department of Chemical Sciences University of Napoli “Federico II” Napoli Italy
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10
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Steele HBB, Elmer-Dixon MM, Rogan JT, Ross JBA, Bowler BE. The Human Cytochrome c Domain-Swapped Dimer Facilitates Tight Regulation of Intrinsic Apoptosis. Biochemistry 2020; 59:2055-2068. [PMID: 32428404 PMCID: PMC7291863 DOI: 10.1021/acs.biochem.0c00326] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Oxidation of cardiolipin (CL) by cytochrome c (cytc) has been proposed to initiate the intrinsic pathway of apoptosis. Domain-swapped dimer (DSD) conformations of cytc have been reported both by our laboratory and by others. The DSD is an alternate conformer of cytc that could oxygenate CL early in apoptosis. We demonstrate here that the cytc DSD has a set of properties that would provide tighter regulation of the intrinsic pathway. We show that the human DSD is kinetically more stable than horse and yeast DSDs. Circular dichroism data indicate that the DSD has a less asymmetric heme environment, similar to that seen when the monomeric protein binds to CL vesicles at high lipid:protein ratios. The dimer undergoes the alkaline conformational transition near pH 7.0, 2.5 pH units lower than that of the monomer. Data from fluorescence correlation spectroscopy and fluorescence anisotropy suggest that the alkaline transition of the DSD may act as a switch from a high affinity for CL nanodiscs at pH 7.4 to a much lower affinity at pH 8.0. Additionally, the peroxidase activity of the human DSD increases 7-fold compared to that of the monomer at pH 7 and 8, but by 14-fold at pH 6 when mixed Met80/H2O ligation replaces the lysine ligation of the alkaline state. We also present data that indicate that cytc binding shows a cooperative effect as the concentration of cytc is increased. The DSD appears to have evolved into a pH-inducible switch that provides a means to control activation of apoptosis near pH 7.0.
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Affiliation(s)
- Harmen B. B. Steele
- Department of Chemistry & Biochemistry, University of Montana, Missoula, Montana 59812, United States
- Center for Biomolecular Structure & Dynamics, University of Montana, Missoula, Montana 59812, United States
| | - Margaret M. Elmer-Dixon
- Department of Chemistry & Biochemistry, University of Montana, Missoula, Montana 59812, United States
- Center for Biomolecular Structure & Dynamics, University of Montana, Missoula, Montana 59812, United States
| | - James T. Rogan
- Department of Chemistry & Biochemistry, University of Montana, Missoula, Montana 59812, United States
| | - J. B. Alexander Ross
- Department of Chemistry & Biochemistry, University of Montana, Missoula, Montana 59812, United States
- Center for Biomolecular Structure & Dynamics, University of Montana, Missoula, Montana 59812, United States
| | - Bruce E. Bowler
- Department of Chemistry & Biochemistry, University of Montana, Missoula, Montana 59812, United States
- Center for Biomolecular Structure & Dynamics, University of Montana, Missoula, Montana 59812, United States
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11
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Govind C, Paul M, Karunakaran V. Ultrafast Heme Relaxation Dynamics Probing the Unfolded States of Cytochrome c Induced by Liposomes: Effect of Charge of Phospholipids. J Phys Chem B 2020; 124:2769-2777. [DOI: 10.1021/acs.jpcb.9b11957] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Chinju Govind
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695 019, Kerala, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Megha Paul
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695 019, Kerala, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Venugopal Karunakaran
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695 019, Kerala, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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12
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Deng Y, Weaver ML, Hoke KR, Pletneva EV. A Heme Propionate Staples the Structure of Cytochrome c for Methionine Ligation to the Heme Iron. Inorg Chem 2019; 58:14085-14106. [PMID: 31589413 DOI: 10.1021/acs.inorgchem.9b02111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ligand-switch reactions at the heme iron are common in biological systems, but their mechanisms and the features of the polypeptide fold that support dual ligation are not well understood. In cytochrome c (cyt c), two low-stability loops (Ω-loop C and Ω-loop D) are connected by the heme propionate HP6. At alkaline pH, the native Met80 ligand from Ω-loop D switches to a Lys residue from the same loop. Deprotonation of an as yet unknown group triggers the alkaline transition. We have created the two cyt c variants T49V/K79G and T78V/K79G with altered connections of these two loops to HP6. Electronic absorption, NMR, and EPR studies demonstrate that at pH 7.4 ferric forms of these variants are Lys-ligated, whereas ferrous forms maintain the native Met80 ligation. Measurements of protein stability, cyclic voltammetry, pH-jump and gated electron-transfer kinetics have revealed that these Thr to Val substitutions greatly affect the alkaline transition in both ferric and ferrous proteins. The substitutions modify the stability of the Met-ligated species and reduction potentials of the heme iron. The kinetics of ligand-switch processes are also altered, and analyses of these effects implicate redox-dependent differences in metal-ligand interactions and the role of the protein dynamics, including cross-talk between the two Ω-loops. With the two destabilized variants, it is possible to map energy levels for the Met- and Lys-ligated species in both ferric and ferrous proteins and assess the role of the protein scaffold in redox-dependent preferences for these two ligands. The estimated shift in the heme iron reduction potential upon deprotonation of the "trigger" group is consistent with those associated with deprotonation of an HP, suggesting that HP6, on its own or as a part of a hydrogen-bonded cluster, is a likely "trigger" for the Met to Lys ligand switch.
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Affiliation(s)
- Yunling Deng
- Department of Chemistry , Dartmouth College , Hanover , New Hampshire 03755 , United States
| | - Madeline L Weaver
- Department of Chemistry and Biochemistry , Berry College , Mount Berry , Georgia 30149 , United States
| | - Kevin R Hoke
- Department of Chemistry and Biochemistry , Berry College , Mount Berry , Georgia 30149 , United States
| | - Ekaterina V Pletneva
- Department of Chemistry , Dartmouth College , Hanover , New Hampshire 03755 , United States
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13
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Elmer-Dixon MM, Bowler BE. Electrostatic Constituents of the Interaction of Cardiolipin with Site A of Cytochrome c. Biochemistry 2018; 57:5683-5695. [DOI: 10.1021/acs.biochem.8b00704] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Margaret M. Elmer-Dixon
- Department of Chemistry and Biochemistry, Center for Bimolecular Structure and Dynamics, University of Montana, Missoula, Montana 59812, United States
| | - Bruce E. Bowler
- Department of Chemistry and Biochemistry, Center for Bimolecular Structure and Dynamics, University of Montana, Missoula, Montana 59812, United States
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14
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Influence of heme c attachment on heme conformation and potential. J Biol Inorg Chem 2018; 23:1073-1083. [PMID: 30143872 DOI: 10.1007/s00775-018-1603-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 08/16/2018] [Indexed: 10/28/2022]
Abstract
Heme c is characterized by its covalent attachment to a polypeptide. The attachment is typically to a CXXCH motif in which the two Cys form thioether bonds with the heme, "X" can be any amino acid other than Cys, and the His serves as a heme axial ligand. Some cytochromes c, however, contain heme attachment motifs with three or four intervening residues in a CX3CH or CX4CH motif. Here, the impacts of these variations in the heme attachment motif on heme ruffling and electronic structure are investigated by spectroscopically characterizing CX3CH and CX4CH variants of Hydrogenobacter thermophilus cytochrome c552. In addition, a novel CXCH variant is studied. 1H and 13C NMR, EPR, and resonance Raman spectra of the protein variants are analyzed to deduce the extent of ruffling using previously reported relationships between these spectral data and heme ruffling. In addition, the reduction potentials of these protein variants are measured using protein film voltammetry. The CXCH and CX4CH variants are found to have enhanced heme ruffling and lower reduction potentials. Implications of these results for the use of these noncanonical motifs in nature, and for the engineering of novel heme peptide structures, are discussed.
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15
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Sterically induced distortions of nickel(II) porphyrins – Comprehensive investigation by DFT calculations and resonance Raman spectroscopy. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2017.12.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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16
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Hu C, Yu Y, Wang J. Improving artificial metalloenzymes' activity by optimizing electron transfer. Chem Commun (Camb) 2017; 53:4173-4186. [DOI: 10.1039/c6cc09921a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This feature article discusses the strategies to optimize electron transfer efficiency, towards enhancing the activity of artificial metalloenzymes.
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Affiliation(s)
- Cheng Hu
- Laboratory of RNA Biology
- Institute of Biophysics
- Chinese Academy of Sciences
- Chaoyang District
- China
| | - Yang Yu
- Tianjin Institute of Industrial Biotechnology
- Chinese Academy of Sciences
- Tianjin 300308
- China
| | - Jiangyun Wang
- Laboratory of RNA Biology
- Institute of Biophysics
- Chinese Academy of Sciences
- Chaoyang District
- China
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