1
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Yang X, Liu S, Yin Z, Chen M, Song J, Li P, Yang L. New insights into the proton pumping mechanism of ba 3 cytochrome c oxidase: the functions of key residues and water. Phys Chem Chem Phys 2023; 25:25105-25115. [PMID: 37461851 DOI: 10.1039/d3cp01334k] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
As the terminal oxidase of cell respiration in mitochondria and aerobic bacteria, the proton pumping mechanism of ba3-type cytochrome c oxidase (CcO) of Thermus thermophiles is still not fully understood. Especially, the functions of key residues which were considered as the possible proton loading sites (PLSs) above the catalytic center, as well as water located above and within the catalytic center, remain unclear. In this work, molecular dynamic simulations were performed on a set of designed mutants of key residues (Asp287, Asp372, His376, and Glu126II). The results showed that Asp287 may not be a PLS, but it could modulate the ability of the proton transfer pathway to transfer protons through its salt bridge with Arg225. Maintaining the closed state of the water pool above the catalytic center is necessary for the participation of inside water molecules in proton transfer. Water molecules inside the water pool can form hydrogen bond chains with PLS to facilitate proton transfer. Additional quantum cluster models of the Fe-Cu metal catalytic center are established, indicating that when the proton is transferred from Tyr237, it is more likely to reach the OCu atom directly through only one water molecule. This work provides a more profound understanding of the functions of important residues and specific water molecules in the proton pumping mechanism of CcO.
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Affiliation(s)
- Xiaoyue Yang
- School of Pharmaceutical Sciences & Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, Henan 450001, China.
| | - Shaohui Liu
- School of Pharmaceutical Sciences & Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, Henan 450001, China.
| | - Zhili Yin
- School of Pharmaceutical Sciences & Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, Henan 450001, China.
| | - Mengguo Chen
- School of Pharmaceutical Sciences & Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, Henan 450001, China.
| | - Jinshuai Song
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Henan 450001, China
| | - Pengfei Li
- Department of Chemistry and Biochemistry, Loyola University Chicago, Illinois 60660, USA
| | - Longhua Yang
- School of Pharmaceutical Sciences & Key Laboratory of Advanced Drug Preparation Technologies, Zhengzhou University, Henan 450001, China.
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2
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Abstract
We present a brief review of the mitochondrial respiratory chain with emphasis on complexes I, III and IV, which contribute to the generation of protonmotive force across the inner mitochondrial membrane, and drive the synthesis of ATP by the process called oxidative phosphorylation. The basic structural and functional details of these complexes are discussed. In addition, we briefly review the information on the so-called supercomplexes, aggregates of complexes I-IV, and summarize basic physiological aspects of cell respiration.
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Affiliation(s)
- Mårten Wikström
- HiLife Institute of Biotechnology, University of Helsinki, Biocenter, Viikinkaari, Helsinki, Finland.
| | - Cristina Pecorilla
- Department of Physics, University of Helsinki, Gustaf Hällströmin katu, Helsinki, Finland
| | - Vivek Sharma
- HiLife Institute of Biotechnology, University of Helsinki, Biocenter, Viikinkaari, Helsinki, Finland; Department of Physics, University of Helsinki, Gustaf Hällströmin katu, Helsinki, Finland
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3
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Du WGH, Götz AW, Noodleman L. Mössbauer Property Calculations on Fea33+∙∙∙H2O∙∙∙CuB2+ Dinuclear Center Models of the Resting Oxidized as-Isolated Cytochrome c Oxidase. Chemphyschem 2022; 23:e202100831. [PMID: 35142420 PMCID: PMC9054037 DOI: 10.1002/cphc.202100831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 02/03/2022] [Indexed: 11/24/2022]
Abstract
Mössbauer isomer shift and quadrupole splitting properties have been calculated using the OLYP‐D3(BJ) density functional method on previously obtained (W.‐G. Han Du, et al., Inorg Chem. 2020, 59, 8906–8915) geometry optimized Fea33+−H2O−CuB2+ dinuclear center (DNC) clusters of the resting oxidized (O state) “as‐isolated” cytochrome c oxidase (CcO). The calculated results are highly consistent with the available experimental observations. The calculations have also shown that the structural heterogeneities of the O state DNCs implicated by the Mössbauer experiments are likely consequences of various factors, particularly the variable positions of the central H2O molecule between the Fea33+ and CuB2+ sites in different DNCs, whether or not this central H2O molecule has H‐bonding interaction with another H2O molecule, the different spin states having similar energies for the Fea33+ sites, and whether the Fea33+ and CuB2+ sites are ferromagnetically or antiferromagnetically spin‐coupled.
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Affiliation(s)
- Wen-Ge Han Du
- The Scripps Research Institute, Integrative Structural and Computational Biology, UNITED STATES
| | | | - Louis Noodleman
- The Scripps Research Institute, Department of Integrative Structural and Computational Biology, Hz112, 10550 North Torrey Pines Road, 92037, La Jolla, UNITED STATES
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4
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Jose A, Schaefer AW, Roveda AC, Transue WJ, Choi SK, Ding Z, Gennis RB, Solomon EI. The three-spin intermediate at the O-O cleavage and proton-pumping junction in heme-Cu oxidases. Science 2021; 373:1225-1229. [PMID: 34516790 DOI: 10.1126/science.abh3209] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Anex Jose
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Andrew W Schaefer
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Antonio C Roveda
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Wesley J Transue
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Sylvia K Choi
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - Ziqiao Ding
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - Robert B Gennis
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - Edward I Solomon
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA 94025, USA
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5
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Reed CJ, Lam QN, Mirts EN, Lu Y. Molecular understanding of heteronuclear active sites in heme-copper oxidases, nitric oxide reductases, and sulfite reductases through biomimetic modelling. Chem Soc Rev 2021; 50:2486-2539. [PMID: 33475096 PMCID: PMC7920998 DOI: 10.1039/d0cs01297a] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Heme-copper oxidases (HCO), nitric oxide reductases (NOR), and sulfite reductases (SiR) catalyze the multi-electron and multi-proton reductions of O2, NO, and SO32-, respectively. Each of these reactions is important to drive cellular energy production through respiratory metabolism and HCO, NOR, and SiR evolved to contain heteronuclear active sites containing heme/copper, heme/nonheme iron, and heme-[4Fe-4S] centers, respectively. The complexity of the structures and reactions of these native enzymes, along with their large sizes and/or membrane associations, make it challenging to fully understand the crucial structural features responsible for the catalytic properties of these active sites. In this review, we summarize progress that has been made to better understand these heteronuclear metalloenzymes at the molecular level though study of the native enzymes along with insights gained from biomimetic models comprising either small molecules or proteins. Further understanding the reaction selectivity of these enzymes is discussed through comparisons of their similar heteronuclear active sites, and we offer outlook for further investigations.
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Affiliation(s)
- Christopher J Reed
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA.
| | - Quan N Lam
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA
| | - Evan N Mirts
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA and Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA. and Department of Biochemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA and Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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6
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Noodleman L, Han Du WG, McRee D, Chen Y, Goh T, Götz AW. Coupled transport of electrons and protons in a bacterial cytochrome c oxidase-DFT calculated properties compared to structures and spectroscopies. Phys Chem Chem Phys 2021; 22:26652-26668. [PMID: 33231596 DOI: 10.1039/d0cp04848h] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
After a general introduction to the features and mechanisms of cytochrome c oxidases (CcOs) in mitochondria and aerobic bacteria, we present DFT calculated physical and spectroscopic properties for the catalytic reaction cycle compared with experimental observations in bacterial ba3 type CcO, also with comparisons/contrasts to aa3 type CcOs. The Dinuclear Complex (DNC) is the active catalytic reaction center, containing a heme a3 Fe center and a near lying Cu center (called CuB) where by successive reduction and protonation, molecular O2 is transformed to two H2O molecules, and protons are pumped from an inner region across the membrane to an outer region by transit through the CcO integral membrane protein. Structures, energies and vibrational frequencies for Fe-O and O-O modes are calculated by DFT over the catalytic cycle. The calculated DFT frequencies in the DNC of CcO are compared with measured frequencies from Resonance Raman spectroscopy to clarify the composition, geometry, and electronic structures of different intermediates through the reaction cycle, and to trace reaction pathways. X-ray structures of the resting oxidized state are analyzed with reference to the known experimental reaction chemistry and using DFT calculated structures in fitting observed electron density maps. Our calculations lead to a new proposed reaction pathway for coupling the PR → F → OH (ferryl-oxo → ferric-hydroxo) pathway to proton pumping by a water shift mechanism. Through this arc of the catalytic cycle, major shifts in pKa's of the special tyrosine and a histidine near the upper water pool activate proton transfer. Additional mechanisms for proton pumping are explored, and the role of the CuB+ (cuprous state) in controlling access to the dinuclear reaction site is proposed.
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Affiliation(s)
- Louis Noodleman
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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7
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Singha A, Mondal A, Nayek A, Dey SG, Dey A. Oxygen Reduction by Iron Porphyrins with Covalently Attached Pendent Phenol and Quinol. J Am Chem Soc 2020; 142:21810-21828. [PMID: 33320658 DOI: 10.1021/jacs.0c10385] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Phenols and quinols participate in both proton transfer and electron transfer processes in nature either in distinct elementary steps or in a concerted fashion. Recent investigations using synthetic heme/Cu models and iron porphyrins have indicated that phenols/quinols can react with both ferric superoxide and ferric peroxide intermediates formed during O2 reduction through a proton coupled electron transfer (PCET) process as well as via hydrogen atom transfer (HAT). Oxygen reduction by iron porphyrins bearing covalently attached pendant phenol and quinol groups is investigated. The data show that both of these can electrochemically reduce O2 selectively by 4e-/4H+ to H2O with very similar rates. However, the mechanism of the reaction, investigated both using heterogeneous electrochemistry and by trapping intermediates in organic solutions, can be either PCET or HAT and is governed by the thermodynamics of these intermediates involved. The results suggest that, while the reduction of the FeIII-O2̇- species to FeIII-OOH proceeds via PCET when a pendant phenol is present, it follows a HAT pathway with a pendant quinol. In the absence of the hydroxyl group the O2 reduction proceeds via an electron transfer followed by proton transfer to the FeIII-O2̇- species. The hydrogen bonding from the pendant phenol group to FeIII-O2̇- and FeIII-OOH species provides a unique advantage to the PCET process by lowering the inner-sphere reorganization energy by limiting the elongation of the O-O bond upon reduction.
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Affiliation(s)
- Asmita Singha
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata 700032, India
| | - Arnab Mondal
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata 700032, India
| | - Abhijit Nayek
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata 700032, India
| | - Somdatta Ghosh Dey
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata 700032, India
| | - Abhishek Dey
- School of Chemical Science, Indian Association for the Cultivation of Science, 2A Raja SC Mullick Road, Kolkata 700032, India
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8
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Han Du WG, McRee D, Götz AW, Noodleman L. A Water Molecule Residing in the Fe a33+···Cu B2+ Dinuclear Center of the Resting Oxidized as-Isolated Cytochrome c Oxidase: A Density Functional Study. Inorg Chem 2020; 59:8906-8915. [PMID: 32525689 PMCID: PMC8114904 DOI: 10.1021/acs.inorgchem.0c00724] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Indexed: 11/30/2022]
Abstract
Although the dinuclear center (DNC) of the resting oxidized "as-isolated" cytochrome c oxidase (CcO) is not a catalytically active state, its detailed structure, especially the nature of the bridging species between the Fea33+ and CuB2+ metal sites, is still both relevant and unsolved. Recent crystallographic work has shown an extended electron density for a peroxide type dioxygen species (O1-O2) bridging the Fea3 and CuB centers. In this paper, our density functional theory (DFT) calculations show that the observed peroxide type electron density between the two metal centers is most likely a mistaken analysis due to overlap of the electron density of a water molecule located at different positions between apparent O1 and O2 sites in DNCs of different CcO molecules with almost the same energy. Because the diffraction pattern and the resulting electron density map represent the effective long-range order averaged over many molecules and unit cells in the X-ray structure, this averaging can lead to an apparent observed superposition of different water positions between the Fea33+ and CuB2+ metal sites.
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Affiliation(s)
- Wen-Ge Han Du
- Department
of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Duncan McRee
- Department
of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Andreas W. Götz
- San
Diego Supercomputer Center, University of
California San Diego, 9500 Gilman Drive MC0505, La Jolla, California 92093, United States
| | - Louis Noodleman
- Department
of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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9
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Ghorai S, Jemmis ED. DFT Study of C–C and C–N Coupling on a Quintuple-Bonded Cr2 Template: MECP (Minimum Energy Crossing Point) Barriers Control Product Distribution. Organometallics 2020. [DOI: 10.1021/acs.organomet.9b00841] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Sagar Ghorai
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Eluvathingal D. Jemmis
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
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10
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Pietra F. A New Route for Dioxygen Activation Uncovered from Quantum Mechanics Investigations of X‐Ray‐Diffraction‐Captured Intermediates of the Ferroxidase Reaction of Ferritins from Gram‐Negative Bacteria. ADVANCED THEORY AND SIMULATIONS 2020. [DOI: 10.1002/adts.201900253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Francesco Pietra
- Accademia Lucchese di Scienze Lettere e ArtiClasse di Scienze, Palazzo Pretorio Via Vittorio Veneto 1 I‐55100 Lucca Italy
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11
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Han Du WG, Götz AW, Noodleman L. DFT Fe a3-O/O-O Vibrational Frequency Calculations over Catalytic Reaction Cycle States in the Dinuclear Center of Cytochrome c Oxidase. Inorg Chem 2019; 58:13933-13944. [PMID: 31566371 PMCID: PMC6839913 DOI: 10.1021/acs.inorgchem.9b01840] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Density functional vibrational frequency calculations have been performed on eight geometry optimized cytochrome c oxidase (CcO) dinuclear center (DNC) reaction cycle intermediates and on the oxymyoglobin (oxyMb) active site. The calculated Fe-O and O-O stretching modes and their frequency shifts along the reaction cycle have been compared with the available resonance Raman (rR) measurements. The calculations support the proposal that in state A[Fea33+-O2-•···CuB+] of CcO, O2 binds with Fea32+ in a similar bent end-on geometry to that in oxyMb. The calculations show that the observed 20 cm-1 shift of the Fea3-O stretching mode from the PR to F state is caused by the protonation of the OH- ligand on CuB2+ (PR[Fea34+═O2-···HO--CuB2+] → F[Fea34+═O2-···H2O-CuB2+]), and that the H2O ligand is still on the CuB2+ site in the rR identified F[Fea34+═O2-···H2O-CuB2+] state. Further, the observed rR band at 356 cm-1 between states PR and F is likely an O-Fea3-porphyrin bending mode. The observed 450 cm-1 low Fea3-O frequency mode for the OH active oxidized state has been reproduced by our calculations on a nearly symmetrically bridged Fea33+-OH-CuB2+ structure with a relatively long Fea3-O distance near 2 Å. Based on Badger's rule, the calculated Fea3-O distances correlate well with the calculated νFe-O-2/3 (νFe-O is the Fea3-O stretching frequency) with correlation coefficient R = 0.973.
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Affiliation(s)
- Wen-Ge Han Du
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037
| | - Andreas W. Götz
- San Diego Supercomputer Center, University of California San Diego, 9500 Gilman Drive MC0505, La Jolla, CA 92093
| | - Louis Noodleman
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037
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12
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Geometric and Electronic Structure Contributions to O-O Cleavage and the Resultant Intermediate Generated in Heme-Copper Oxidases. J Am Chem Soc 2019; 141:10068-10081. [PMID: 31146528 DOI: 10.1021/jacs.9b04271] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This study investigates the mechanism of O-O bond cleavage in heme-copper oxidase (HCO) enzymes, combining experimental and computational insights from enzyme intermediates and synthetic models. It is determined that HCOs undergo a proton-initiated O-O cleavage mechanism where a single water molecule in the active site enables proton transfer (PT) from the cross-linked tyrosine to a peroxo ligand bridging the heme FeIII and CuII, and multiple H-bonding interactions lower the tyrosine p Ka. Due to sterics within the active site, the proton must either transfer initially to the O(Fe) (a high-energy intermediate), or from another residue over a ∼10 Å distance to reach the O(Cu) atom directly. While the distance between the H+ donor (Tyr) and acceptor (O(Cu)) results in a barrier to PT, this separation is critical for the low barrier to O-O cleavage as it enhances backbonding from Fe into the O22- σ* orbital. Thus, PT from Tyr precedes O-O elongation and is rate-limiting, consistent with available kinetic data. The electron transfers from tyrosinate after the barrier via a superexchange pathway provided by the cross-link, generating intermediate PM. PM is evaluated using available experimental data. The geometric structure contains an FeIV═O that is H-bonded to the CuII-OH. The electronic structure is a singlet, where the FeIV and CuII are antiferromagnetically coupled through the H-bond between the oxo(Fe) and hydroxo(Cu) ligands, while the CuII and Tyr• are ferromagnetically coupled due their delocalization into orthogonal magnetic orbitals on the cross-linked His residue. These findings provide critical insights into the mechanism of efficient O2 reduction in HCOs, and the nature of the PM intermediate that couples this reaction to proton pumping.
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13
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Adam SM, Wijeratne GB, Rogler PJ, Diaz DE, Quist DA, Liu JJ, Karlin KD. Synthetic Fe/Cu Complexes: Toward Understanding Heme-Copper Oxidase Structure and Function. Chem Rev 2018; 118:10840-11022. [PMID: 30372042 PMCID: PMC6360144 DOI: 10.1021/acs.chemrev.8b00074] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heme-copper oxidases (HCOs) are terminal enzymes on the mitochondrial or bacterial respiratory electron transport chain, which utilize a unique heterobinuclear active site to catalyze the 4H+/4e- reduction of dioxygen to water. This process involves a proton-coupled electron transfer (PCET) from a tyrosine (phenolic) residue and additional redox events coupled to transmembrane proton pumping and ATP synthesis. Given that HCOs are large, complex, membrane-bound enzymes, bioinspired synthetic model chemistry is a promising approach to better understand heme-Cu-mediated dioxygen reduction, including the details of proton and electron movements. This review encompasses important aspects of heme-O2 and copper-O2 (bio)chemistries as they relate to the design and interpretation of small molecule model systems and provides perspectives from fundamental coordination chemistry, which can be applied to the understanding of HCO activity. We focus on recent advancements from studies of heme-Cu models, evaluating experimental and computational results, which highlight important fundamental structure-function relationships. Finally, we provide an outlook for future potential contributions from synthetic inorganic chemistry and discuss their implications with relevance to biological O2-reduction.
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Affiliation(s)
- Suzanne M. Adam
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Gayan B. Wijeratne
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Patrick J. Rogler
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Daniel E. Diaz
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - David A. Quist
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jeffrey J. Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kenneth D. Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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14
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Wikström M, Krab K, Sharma V. Oxygen Activation and Energy Conservation by Cytochrome c Oxidase. Chem Rev 2018; 118:2469-2490. [PMID: 29350917 PMCID: PMC6203177 DOI: 10.1021/acs.chemrev.7b00664] [Citation(s) in RCA: 233] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
![]()
This review focuses on the type
A cytochrome c oxidases (CcO), which
are found in all mitochondria
and also in several aerobic bacteria. CcO catalyzes
the respiratory reduction of dioxygen (O2) to water by
an intriguing mechanism, the details of which are fairly well understood
today as a result of research for over four decades. Perhaps even
more intriguingly, the membrane-bound CcO couples
the O2 reduction chemistry to translocation of protons
across the membrane, thus contributing to generation of the electrochemical
proton gradient that is used to drive the synthesis of ATP as catalyzed
by the rotary ATP synthase in the same membrane. After reviewing the
structure of the core subunits of CcO, the active
site, and the transfer paths of electrons, protons, oxygen, and water,
we describe the states of the catalytic cycle and point out the few
remaining uncertainties. Finally, we discuss the mechanism of proton
translocation and the controversies in that area that still prevail.
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Affiliation(s)
- Mårten Wikström
- Institute of Biotechnology , University of Helsinki , P.O. Box 56 , Helsinki FI-00014 , Finland
| | - Klaas Krab
- Department of Molecular Cell Physiology , Vrije Universiteit , P.O. Box 7161 , Amsterdam 1007 MC , The Netherlands
| | - Vivek Sharma
- Institute of Biotechnology , University of Helsinki , P.O. Box 56 , Helsinki FI-00014 , Finland.,Department of Physics , University of Helsinki , P.O. Box 64 , Helsinki FI-00014 , Finland
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15
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Han Du WG, Götz AW, Noodleman L. A Water Dimer Shift Activates a Proton Pumping Pathway in the P R → F Transition of ba 3 Cytochrome c Oxidase. Inorg Chem 2018; 57:1048-1059. [PMID: 29308889 DOI: 10.1021/acs.inorgchem.7b02461] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Broken-symmetry density functional calculations have been performed on the [Fea34+,CuB2+] state of the dinuclear center (DNC) for the PR → F part of the catalytic cycle of ba3 cytochrome c oxidase (CcO) from Thermus thermophilus (Tt), using the OLYP-D3-BJ functional. The calculations show that the movement of the H2O molecules in the DNC affects the pKa values of the residue side chains of Tyr237 and His376+, which are crucial for proton transfer/pumping in ba3 CcO from Tt. The calculated lowest energy structure of the DNC in the [Fea34+,CuB2+] state (state F) is of the form Fea34+═O2-···CuB2+, in which the H2O ligand that resulted from protonation of the OH- ligand in the PR state is dissociated from the CuB2+ site. The calculated Fea34+═O2- distance in F (1.68 Å) is 0.03 Å longer than that in PR (1.65 Å), which can explain the different Fea34+═O2- stretching modes in P (804 cm-1) and F (785 cm-1) identified by resonance Raman experiments. In this F state, the CuB2+···O2- (ferryl-oxygen) distance is only around 2.4 Å. Hence, the subsequent OH state [Fea33+-OH--CuB2+] with a μ-hydroxo bridge can be easily formed, as shown by our calculations.
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Affiliation(s)
- Wen-Ge Han Du
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Andreas W Götz
- San Diego Supercomputer Center, University of California San Diego , 9500 Gilman Drive MC0505, La Jolla, California 92093, United States
| | - Louis Noodleman
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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Bie L, Liu F, Li Y, Dong T, Gao J, Du L, Yuan Q. Spin crossover dynamics studies on the thermally activated molecular oxygen binding mechanism on a model copper complex. Phys Chem Chem Phys 2018; 20:15852-15862. [DOI: 10.1039/c8cp02482k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The theoretical description of the primary dioxygen (O2) binding and activation step in many copper or iron enzymes, suffers from the instrinsically electronic non-adiabaticity of the spin flip events of the triplet dioxygen molecule (3O2), mediated by spin–orbit couplings.
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Affiliation(s)
- Lihua Bie
- Hubei Key Laboratory of Agricultural Bioinformatics
- College of Informatics
- Huazhong Agricultural University
- Wuhan
- P. R. China
| | - Fang Liu
- Hubei Key Laboratory of Agricultural Bioinformatics
- College of Informatics
- Huazhong Agricultural University
- Wuhan
- P. R. China
| | - Yanwei Li
- Environment Research Institute
- Shandong University
- Jinan
- P. R. China
| | - Tiange Dong
- Hubei Key Laboratory of Agricultural Bioinformatics
- College of Informatics
- Huazhong Agricultural University
- Wuhan
- P. R. China
| | - Jun Gao
- Hubei Key Laboratory of Agricultural Bioinformatics
- College of Informatics
- Huazhong Agricultural University
- Wuhan
- P. R. China
| | - Likai Du
- Hubei Key Laboratory of Agricultural Bioinformatics
- College of Informatics
- Huazhong Agricultural University
- Wuhan
- P. R. China
| | - Qiaoxia Yuan
- College of Engineering
- Huazhong Agricultural University
- Wuhan 430070
- P. R. China
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Kamnev AA, Tugarova AV. Sample treatment in Mössbauer spectroscopy for protein-related analyses: Nondestructive possibilities to look inside metal-containing biosystems. Talanta 2017; 174:819-837. [PMID: 28738659 DOI: 10.1016/j.talanta.2017.06.057] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 06/01/2017] [Accepted: 06/19/2017] [Indexed: 01/07/2023]
Abstract
In this review, the unique possibilities are considered of the 57Fe transmission (TMS) and 57Co emission (EMS) variants of Mössbauer (nuclear γ-resonance) spectroscopy as nondestructive techniques with minimal sample preparation/treatment and a significant analytical potential, with a focus on the analysis of cation-binding sites in metalloproteins. The techniques are shown to provide unique structural and quantitative information on the coordination microenvironment, the chemical state and transformations of the Mössbauer nuclides in sophisticated metal-containing proteins, including those within complicated supramolecular structures, and in microbial cells or tissues. Recent representative examples of analyses of Fe-containing proteins by 57Fe TMS are briefly discussed, along with the newly emerging data on using 57Co EMS for probing the structural organisation of 57Co-doped cation-binding sites in sophisticated biocomplexes including metalloenzymes. Finally, some rare or exotic applications of Mössbauer spectroscopy (including the synchrotron-based methodology) in protein-related studies are outlined.
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Affiliation(s)
- Alexander A Kamnev
- Laboratory of Biochemistry, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 13 Prosp. Entuziastov, 410049, Saratov, Russia.
| | - Anna V Tugarova
- Laboratory of Biochemistry, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 13 Prosp. Entuziastov, 410049, Saratov, Russia
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Abstract
The quantum chemical cluster approach is a powerful method for investigating enzymatic reactions. Over the past two decades, a large number of highly diverse systems have been studied and a great wealth of mechanistic insight has been developed using this technique. This Perspective reviews the current status of the methodology. The latest technical developments are highlighted, and challenges are discussed. Some recent applications are presented to illustrate the capabilities and progress of this approach, and likely future directions are outlined.
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Affiliation(s)
- Fahmi Himo
- Arrhenius Laboratory, Department of Organic Chemistry, Stockholm University , SE-106 91 Stockholm, Sweden
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Han Du WG, Götz AW, Yang L, Walker RC, Noodleman L. A broken-symmetry density functional study of structures, energies, and protonation states along the catalytic O-O bond cleavage pathway in ba3 cytochrome c oxidase from Thermus thermophilus. Phys Chem Chem Phys 2016; 18:21162-71. [PMID: 27094074 DOI: 10.1039/c6cp00349d] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Broken-symmetry density functional calculations have been performed on the [Fea3, CuB] dinuclear center (DNC) of ba3 cytochrome c oxidase from Thermus thermophilus in the states of [Fea3(3+)-(HO2)(-)-CuB(2+), Tyr237(-)] and [Fea3(4+)[double bond, length as m-dash]O(2-), OH(-)-CuB(2+), Tyr237˙], using both PW91-D3 and OLYP-D3 functionals. Tyr237 is a special tyrosine cross-linked to His233, a ligand of CuB. The calculations have shown that the DNC in these states strongly favors the protonation of His376, which is above propionate-A, but not of the carboxylate group of propionate-A. The energies of the structures obtained by constrained geometry optimizations along the O-O bond cleavage pathway between [Fea3(3+)-(O-OH)(-)-CuB(2+), Tyr237(-)] and [Fea3(4+)[double bond, length as m-dash]O(2-)HO(-)-CuB(2+), Tyr237˙] have also been calculated. The transition of [Fea3(3+)-(O-OH)(-)-CuB(2+), Tyr237(-)] → [Fea3(4+)[double bond, length as m-dash]O(2-)HO(-)-CuB(2+), Tyr237˙] shows a very small barrier, which is less than 3.0/2.0 kcal mol(-1) in PW91-D3/OLYP-D3 calculations. The protonation state of His376 does not affect this O-O cleavage barrier. The rate limiting step of the transition from state A (in which O2 binds to Fea3(2+)) to state PM ([Fea3(4+)[double bond, length as m-dash]O(2-), OH(-)-CuB(2+), Tyr237˙], where the O-O bond is cleaved) in the catalytic cycle is, therefore, the proton transfer originating from Tyr237 to O-O to form the hydroperoxo [Fea3(3+)-(O-OH)(-)-CuB(2+), Tyr237(-)] state. The importance of His376 in proton uptake and the function of propionate-A/neutral-Asp372 as a gate to prevent the proton from back-flowing to the DNC are also shown.
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Affiliation(s)
- Wen-Ge Han Du
- Department of Integrative Structural and Computational Biology, GAC1118, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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