1
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Canonica F, Klose D, Ledermann R, Sauer MM, Abicht HK, Quade N, Gossert AD, Chesnov S, Fischer HM, Jeschke G, Hennecke H, Glockshuber R. Structural basis and mechanism for metallochaperone-assisted assembly of the Cu A center in cytochrome oxidase. SCIENCE ADVANCES 2019; 5:eaaw8478. [PMID: 31392273 PMCID: PMC6669012 DOI: 10.1126/sciadv.aaw8478] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 06/26/2019] [Indexed: 06/10/2023]
Abstract
The mechanisms underlying the biogenesis of the structurally unique, binuclear Cu1.5+•Cu1.5+ redox center (CuA) on subunit II (CoxB) of cytochrome oxidases have been a long-standing mystery. Here, we reconstituted the CoxB•CuA center in vitro from apo-CoxB and the holo-forms of the copper transfer chaperones ScoI and PcuC. A previously unknown, highly stable ScoI•Cu2+•CoxB complex was shown to be rapidly formed as the first intermediate in the pathway. Moreover, our structural data revealed that PcuC has two copper-binding sites, one each for Cu1+ and Cu2+, and that only PcuC•Cu1+•Cu2+ can release CoxB•Cu2+ from the ScoI•Cu2+•CoxB complex. The CoxB•CuA center was then formed quantitatively by transfer of Cu1+ from a second equivalent of PcuC•Cu1+•Cu2+ to CoxB•Cu2+. This metalation pathway is consistent with all available in vivo data and identifies the sources of the Cu ions required for CuA center formation and the order of their delivery to CoxB.
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Affiliation(s)
- Fabia Canonica
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Daniel Klose
- Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | | | - Maximilian M. Sauer
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Helge K. Abicht
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Nick Quade
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Alvar D. Gossert
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Serge Chesnov
- Functional Genomics Center Zurich, University of Zurich/ETH Zurich, Zurich, Switzerland
| | | | - Gunnar Jeschke
- Laboratory of Physical Chemistry, ETH Zurich, Zurich, Switzerland
| | - Hauke Hennecke
- Institute of Microbiology, ETH Zurich, Zurich, Switzerland
| | - Rudi Glockshuber
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
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2
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Synthesis, crystal structure and spectroscopic and electrochemical properties of bridged trisbenzoato copper–zinc heterobinuclear complex of 2,2′-bipyridine. J Mol Struct 2015. [DOI: 10.1016/j.molstruc.2014.11.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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3
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Koch A, Kumar A, Borthakur R, Ozukum O, Lal R. Synthesis and characterization of a copper–zinc heterobinuclear complex of 2,2′-bipyridine. J COORD CHEM 2014. [DOI: 10.1080/00958972.2014.987135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- A. Koch
- Department of Chemistry, North-Eastern Hill University, Shillong, India
| | - A. Kumar
- Faculty of Science and Agriculture, Department of Chemistry, The University of West Indies, St. Augustine, Trinidad and Tobago
| | - R. Borthakur
- Department of Chemistry, North-Eastern Hill University, Shillong, India
| | - O.S. Ozukum
- Department of Chemistry, North-Eastern Hill University, Shillong, India
| | - R.A. Lal
- Department of Chemistry, North-Eastern Hill University, Shillong, India
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4
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Yu F, Cangelosi VM, Zastrow ML, Tegoni M, Plegaria JS, Tebo AG, Mocny CS, Ruckthong L, Qayyum H, Pecoraro VL. Protein design: toward functional metalloenzymes. Chem Rev 2014; 114:3495-578. [PMID: 24661096 PMCID: PMC4300145 DOI: 10.1021/cr400458x] [Citation(s) in RCA: 329] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Fangting Yu
- University of Michigan, Ann Arbor, Michigan 48109, United States
| | | | | | | | | | - Alison G. Tebo
- University of Michigan, Ann Arbor, Michigan 48109, United States
| | | | - Leela Ruckthong
- University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Hira Qayyum
- University of Michigan, Ann Arbor, Michigan 48109, United States
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5
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MAKINO Y. Oxygen Consumption by Fruits and Vegetables. FOOD SCIENCE AND TECHNOLOGY RESEARCH 2013. [DOI: 10.3136/fstr.19.523] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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6
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Arcovito A, della Longa S. Local structure and dynamics of hemeproteins by X-ray absorption near edge structure spectroscopy. J Inorg Biochem 2012; 112:93-9. [PMID: 22541673 DOI: 10.1016/j.jinorgbio.2012.03.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 03/28/2012] [Accepted: 03/29/2012] [Indexed: 11/19/2022]
Abstract
X-ray absorption near edge structure (XANES) spectroscopy is a synchrotron radiation technique sensitive to the local structure and dynamics around the metal site of a heme containing protein. Advances in detection techniques and theoretical/computational platforms in the last 15 years allowed the use of XANES as a quantitative probe of the key structural determinants driving functional changes, both in a concerted way with protein crystallography and EXAFS (extended X-ray absorption fine structure), or as a stand-alone method to apply in the crystal state as well as in solution. Moreover, the local dynamics of the heme site has been deeply investigated, on one hand, coupling XANES to classical photolysis experiments at cryogenic temperatures; on the other hand, the intrinsic property of the synchrotron radiation to induce radiolysis events, has been exploited to investigate specific cryotrapped intermediates, using X-rays both as a pump and a probe. Insights on the XANES method and some specific examples are presented to illustrate these topics.
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Affiliation(s)
- Alessandro Arcovito
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Largo F. Vito 1, 00168 Roma, Italy.
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Chanu OB, Kumar A, Ahmed A, Lal R. Synthesis and characterisation of heterometallic trinuclear copper(II) and zinc(II) complexes derived from bis(2-hydroxy-1-naphthaldehyde)oxaloyldihydrazone. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2011.11.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Kumar A, Lal R, Chanu O, Borthakur R, Koch A, Lemtur A, Adhikari S, Choudhury S. Synthesis and characterization of a binuclear copper(II) complex [Cu(H2slox)]2 from polyfunctional disalicylaldehyde oxaloyldihydrazone and its heterobinuclear copper(II) and molybdenum(VI) complexes. J COORD CHEM 2011. [DOI: 10.1080/00958972.2011.580845] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- A. Kumar
- a Department of Chemistry, Faculty of Science and Agriculture , The University of West-Indies , St. Augustine , Trinidad and Tobago , West-Indies
| | - R.A. Lal
- b Department of Chemistry , North-Eastern Hill University , Shillong – 793 022 , India
| | - O.B. Chanu
- b Department of Chemistry , North-Eastern Hill University , Shillong – 793 022 , India
| | - R. Borthakur
- b Department of Chemistry , North-Eastern Hill University , Shillong – 793 022 , India
| | - A. Koch
- b Department of Chemistry , North-Eastern Hill University , Shillong – 793 022 , India
| | - A. Lemtur
- b Department of Chemistry , North-Eastern Hill University , Shillong – 793 022 , India
| | - S. Adhikari
- c Department of Chemistry , ICV College , Belonia , South Tripura – 799155, Tripura , India
| | - S. Choudhury
- b Department of Chemistry , North-Eastern Hill University , Shillong – 793 022 , India
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9
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Kamiya K, Shigeta Y. First-principles molecular dynamics study on the atomistic behavior of His503 in bovine cytochrome c oxidase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:1328-35. [PMID: 21565155 DOI: 10.1016/j.bbabio.2011.03.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 03/29/2011] [Accepted: 03/30/2011] [Indexed: 11/26/2022]
Abstract
We report first-principles molecular dynamics calculations based on density functional theory performed on the entrance part of the D-path pathway in bovine cytochrome c oxidase. Our models, which are extracted from the fully reduced and oxidized X-ray structures, include His503 as a protonatable site. We find that the protonated His503 with the deprotonated Asp91 [H503-N(δ1)H(+) and D91-C(γ)OO(γ)] are more energetically favorable than other protonation states, [H503-N(δ1) and D91-C(γ)OOH], with an energy difference of about -5kcal/mol in reduced case, while the [H503-N(δ1)H+ and D91-C(γ)OO(-)] state is energetically unstable, about +3kcal/mol higher in energy in the oxidized case. The local interaction of His503 with the surrounding polar residues is necessary and sufficient for determining the energetics. The redox-coupled rotation of His503 is found to change the energetics of the protonation states. We also find that this rotation is coupled with the proton transfer from His503 and Asp91, which leads to the transition between the two different protonation states. This study suggests that His503 is involved in the proton supply to the D-path as a proton acceptor and that the redox-controlled proton-transfer-coupled rotation of His503 is a key process for an effective proton supply to the D-path from water bulk. This article is part of a Special Issue entitled: Allosteric cooperativity in respiratory proteins.
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10
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El Ichi S, Miodek A, Sauriat-Dorizon H, Mahy JP, Henry C, Marzouki MN, Korri-Youssoufi H. Characterization of structure and activity of garlic peroxidase (POX(1B)). J Biol Inorg Chem 2010; 16:157-72. [PMID: 21042820 DOI: 10.1007/s00775-010-0714-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 10/04/2010] [Indexed: 11/29/2022]
Abstract
Structural characterization and study of the activity of new POX(1B) protein from garlic which has a high peroxidase activity and can be used as a biosensor for the detection of hydrogen peroxide and phenolic compounds were performed and compared with the findings for other heme peroxidases. The structure-function relationship was investigated by analysis of the spectroscopic properties and correlated to the structure determined by a new generation of high-performance hybrid mass spectrometers. The reactivity of the enzyme was analyzed by studies of the redox activity toward various ligands and the reactivity with various substrates. We demonstrated that, in the case of garlic peroxidase, the heme group is pentacoordinated, and has an histidine as a proximal ligand. POX(1B) exhibited a high affinity for hydrogen peroxide as well as various reducing cosubstrates. In addition, high enzyme specificity was demonstrated. The k(cat) and K(M) values were 411 and 400 mM(-1) s(-1) for 3,3',5,5'-tetramethylbenzidine and 2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), respectively. Furthermore, the reduction of nitro compounds in the presence of POX(1B) was demonstrated by iron(II) nitrosoalkane complex assay. In addition, POX(1B) showed a great potential for application for drug metabolism since its ability to react with 1-nitrohexane in the presence of sodium dithionite was demonstrated by the appearance of a characteristic Soret band at 411 nm. The high catalytic efficiency obtained in the case of the new garlic peroxidase (POX(1B)) is suitable for the monitoring of different analytes and biocatalysis.
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Affiliation(s)
- Sarra El Ichi
- Equipe de Chimie Bioorganique et Bioinorganique, Institut de Chimie Moléculaire et Matériaux d'Orsay, UMR 8182, CNRS, Université Paris-Sud, Orsay, France
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11
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Bianchetti CM, Blouin GC, Bitto E, Olson JS, Phillips GN. The structure and NO binding properties of the nitrophorin-like heme-binding protein from Arabidopsis thaliana gene locus At1g79260.1. Proteins 2010; 78:917-31. [PMID: 19938152 PMCID: PMC2811769 DOI: 10.1002/prot.22617] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The protein from Arabidopsis thaliana gene locus At1g79260.1 is comprised of 166-residues and is of previously unknown function. Initial structural studies by the Center for Eukaryotic Structural Genomics (CESG) suggested that this protein might bind heme, and consequently, the crystal structures of apo and heme-bound forms were solved to near atomic resolution of 1.32 A and 1.36 A, respectively. The rate of hemin loss from the protein was measured to be 3.6 x 10(-5) s(-1), demonstrating that it binds heme specifically and with high affinity. The protein forms a compact 10-stranded beta-barrel that is structurally similar to the lipocalins and fatty acid binding proteins (FABPs). One group of lipocalins, the nitrophorins (NP), are heme proteins involved in nitric oxide (NO) transport and show both sequence and structural similarity to the protein from At1g79260.1 and two human homologues, all of which contain a proximal histidine capable of coordinating a heme iron. Rapid-mixing and laser photolysis techniques were used to determine the rate constants for carbon monoxide (CO) binding to the ferrous form of the protein (k'(CO) = 0.23 microM(-1) s(-1), k(CO) = 0.050 s(-1)) and NO binding to the ferric form (k'(NO) = 1.2 microM(-1) s(-1), k(NO) = 73 s(-1)). Based on both structural and functional similarity to the nitrophorins, we have named the protein nitrobindin and hypothesized that it plays a role in NO transport. However, one of the two human homologs of nitrobindin contains a THAP domain, implying a possible role in apoptosis. Proteins 2010. (c) 2009 Wiley-Liss, Inc.
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Affiliation(s)
- Christopher M. Bianchetti
- Departments of Biochemistry, University of Wisconsin, Madison, WI 53706, USA,Centers for Eukaryotic Structural Genomics, University of Wisconsin, Madison, WI 53706, USA
| | - George C. Blouin
- Department of Biochemistry and Cell Biology and the W. M. Keck Center for Computational Biology, Rice University, Houston, Texas 77005
| | - Eduard Bitto
- Department of Chemistry and Biochemistry, Georgian Court University, Lakewood NJ 08701
| | - John S. Olson
- Department of Biochemistry and Cell Biology and the W. M. Keck Center for Computational Biology, Rice University, Houston, Texas 77005
| | - George N. Phillips
- Departments of Biochemistry, University of Wisconsin, Madison, WI 53706, USA,Centers for Eukaryotic Structural Genomics, University of Wisconsin, Madison, WI 53706, USA
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12
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Reactive Simulations for Biochemical Processes. ADVANCES IN THE ATOMIC-SCALE MODELING OF NANOSYSTEMS AND NANOSTRUCTURED MATERIALS 2010. [DOI: 10.1007/978-3-642-04650-6_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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13
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Reedy CJ, Elvekrog MM, Gibney BR. Development of a heme protein structure-electrochemical function database. Nucleic Acids Res 2007; 36:D307-13. [PMID: 17933771 PMCID: PMC2238922 DOI: 10.1093/nar/gkm814] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Proteins containing heme, iron(protoporphyrin IX) and its variants, continue to be one of the most-studied classes of biomolecules due to their diverse range of biological functions. The literature is abundant with reports of structural and functional characterization of individual heme proteins which demonstrate that heme protein reduction potential values, Em, span the range from –550 mV to +450 mV versus SHE. In order to unite these data for the purposes of global analysis, a new web-based resource of heme protein structure–function relationships is presented: the Heme Protein Database (HPD). This database is the first of its kind to combine heme protein structural classifications including protein fold, heme type and heme axial ligands, with heme protein reduction potential values in a web-searchable format. The HPD is located at http://heme.chem.columbia.edu/heme.php. The data illustrate that heme protein Em values are modulated over a 300 mV range by the type of global protein fold, a 600 mV range by the type of porphyrin and an 800 mV range by the axial ligands. Thus, the 1 V range observed in heme protein reduction potential values in biological systems arises from subtle combinations of these various factors.
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Affiliation(s)
- Charles J Reedy
- Department of Chemistry, Columbia University, 3000 Broadway, MC 3121, New York, NY 10027, USA
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Seong J, Oh HJ, Kim J, An JH, Kim W. Identification of proteins that regulate radiation-induced apoptosis in murine tumors with wild type p53. JOURNAL OF RADIATION RESEARCH 2007; 48:435-41. [PMID: 17721044 DOI: 10.1269/jrr.07015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
In this study, we investigated the molecular factors determining the induction of apoptosis by radiation. Two murine tumors syngeneic to C3H/HeJ mice were used: an ovarian carcinoma OCa-I, and a hepatocarcinoma HCa-I. Both have wild type p53, but display distinctly different radiosensitivity in terms of specific growth delay (12.7 d in OCa-I and 0.3 d in HCa-I) and tumor cure dose 50% (52.6 Gy in OCa-I and > 80 Gy in HCa-I). Eight-mm tumors on the thighs of mice were irradiated with 25 Gy and tumor samples were collected at regular time intervals after irradiation. The peak levels of apoptosis were 16.1 +/- 0.6% in OCa-I and 0.2 +/- 0.0% in HCa-I at 4 h after radiation, and this time point was used for subsequent proteomics analysis. Protein spots were identified by peptide mass fingerprinting with a focus on those related to apoptosis. In OCa-I tumors, radiation increased the expression of cytochrome c oxidase and Bcl2/adenovirus E1B-interacting 2 (Nip 2) protein higher than 3-fold. However in HCa-I, these two proteins showed no significant change. The results suggest that radiosensitivity in tumors with wild type p53 is regulated by a complex mechanism. Furthermore, these proteins could be molecular targets for a novel therapeutic strategy involving the regulation of radiosensitivity.
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Affiliation(s)
- Jinsil Seong
- Department of Radiation Oncology, Yonsei University Medical College, Seoul, Korea.
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Coyne HJ, Ciofi-Baffoni S, Banci L, Bertini I, Zhang L, George GN, Winge DR. The Characterization and Role of Zinc Binding in Yeast Cox4. J Biol Chem 2007; 282:8926-34. [PMID: 17215247 DOI: 10.1074/jbc.m610303200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Yeast Cox4 is a zinc binding subunit of cytochrome c oxidase. Cox4 is the only cofactor-containing subunit that is not directly part of the catalytic core of the enzyme located in the mitochondrial inner membrane. The Zn(II) site is shown to be distinct from the bovine ortholog, as it results from the x-ray structure of the entire cytochrome c oxidase in having a single histidyl residue and three conserved cysteines residues in the coordination sphere. Substitutions at the Cys ligand positions result in non-functional Cox4 proteins that fail to lead to cytochrome oxidase assembly. Limited function exists in His-119 mutants when overexpressed. Zn(II) binding in Cox4 is, therefore, important for the stability of the complex. The solution structure of yeast Cox4 elucidated by multidimensional NMR reveals a C-terminal globular domain consisting of two beta sheets analogous to the bovine ortholog except the loop containing the coordinating His in the yeast protein and the fourth Cys in the bovine protein are in different positions in the two structures. The conformation of this loop is dictated by the different sequence position of the fourth coordinating zinc ligand. The Zn(II) ion is buried within the domain, consistent with its role in structural stability. Potential functions of this matrix-facing subunit are discussed.
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Affiliation(s)
- H Jerome Coyne
- University of Utah Health Sciences Center, Department of Medicine, Salt Lake City, Utah 84132, USA
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Kobayashi K, Yoshioka S, Kato Y, Asano Y, Aono S. Regulation of Aldoxime Dehydratase Activity by Redox-dependent Change in the Coordination Structure of the Aldoxime-Heme Complex. J Biol Chem 2005; 280:5486-90. [PMID: 15596434 DOI: 10.1074/jbc.m410474200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phenylacetaldoxime dehydratase from Bacillus sp. strain OxB-1 (OxdB) catalyzes the dehydration of Z-phenylacetaldoxime (PAOx) to produce phenylacetonitrile. OxdB contains a protoheme that works as the active center of the dehydration reaction. The enzymatic activity of ferrous OxdB was 1150-fold higher than that of ferric OxdB, indicating that the ferrous heme was the active state in OxdB catalysis. Although ferric OxdB was inactive, the substrate was bound to the ferric heme iron. Electron paramagnetic resonance spectroscopy revealed that the oxygen atom of PAOx was bound to the ferric heme, whereas PAOx was bound to the ferrous heme in OxdB via the nitrogen atom of PAOx. These results show a novel mechanism by which the activity of a heme enzyme is regulated; that is, the oxidation state of the heme controls the coordination structure of a substrate-heme complex, which regulates enzymatic activity. Rapid scanning spectroscopy using stopped-flow apparatus revealed that a reaction intermediate (the PAOx-ferrous OxdB complex) showed Soret, alpha, and beta bands at 415, 555, and 524 nM, respectively. The formation of this intermediate complex was very fast, finishing within the dead time of the stopped-flow mixer (approximately 3 ms). Site-directed mutagenesis revealed that His-306 was the catalytic residue responsible for assisting the elimination of the hydrogen atom of PAOx. The pH dependence of OxdB activity suggested that another amino acid residue that assists the elimination of the OH group of PAOx would work as a catalytic residue along with His-306.
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Affiliation(s)
- Katsuaki Kobayashi
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan
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Affiliation(s)
- Charles J Reedy
- Department of Chemistry, Columbia University, 3000 Broadway, MC 3121, New York, New York 10027, USA
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18
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Affiliation(s)
- Eunsuk Kim
- Department of Chemistry, Johns Hopkins University, Charles and 34th Streets, Baltimore, Maryland 21218, USA
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Kadenbach B, Arnold S, Lee I, Hüttemann M. The possible role of cytochrome c oxidase in stress-induced apoptosis and degenerative diseases. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2004; 1655:400-8. [PMID: 15100056 DOI: 10.1016/j.bbabio.2003.06.005] [Citation(s) in RCA: 169] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2003] [Accepted: 06/25/2003] [Indexed: 10/26/2022]
Abstract
Apoptotic cell death can occur by two different pathways. Type 1 is initiated by the activation of death receptors (Fas, TNF-receptor-family) on the plasma membrane followed by activation of caspase 8. Type 2 involves changes in mitochondrial integrity initiated by various effectors like Ca(2+), reactive oxygen species (ROS), Bax, or ceramide, leading to the release of cytochrome c and activation of caspase 9. The release of cytochrome c is followed by a decrease of the mitochondrial membrane potential DeltaPsi(m). Recent publications have demonstrated, however, that induction of apoptosis by various effectors involves primarily a transient increase of DeltaPsi(m) for unknown reason. Here we propose a new mechanism for the increased DeltaPsi(m) based on experiments on the allosteric ATP-inhibition of cytochrome c oxidase at high matrix ATP/ADP ratios, which was concluded to maintain low levels of DeltaPsi(m) in vivo under relaxed conditions. This regulatory mechanism is based on the potential-dependency of the ATP synthase, which has maximal activity at DeltaPsi(m)=100-120 mV. The mechanism is turned off either through calcium-activated dephosphorylation of cytochrome c oxidase or by 3,5-diiodo-L-thyronine, palmitate, and probably other so far unknown effectors. Consequently, energy metabolism changes to an excited state. We propose that this change causes an increase in DeltaPsi(m), a condition for the formation of ROS and induction of apoptosis.
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Affiliation(s)
- Bernhard Kadenbach
- Fachbereich Chemie, Philipps-Universität, Hans-Meerwein-Strasse, D-35032 Marburg, Germany.
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Abstract
A redox-coupled conformational change in Asp51 of subunit I and a hydrogen-bond network connecting Asp51 with the matrix surface have been deduced from X-ray structures of bovine heart cytochrome c oxidase. This has provided evidence that Asp51 may play a role in the proton pumping process. However, the lack of complete conservation of a residue analogous to Asp51, the inclusion of a peptide bond in the hydrogen-bonding network and the lack of apparent involvement of the O2 reduction site have been used as arguments against the involvement of Asp51 in the mechanism of proton pumping. This minireview re-examines these arguments.
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Affiliation(s)
- Shinya Yoshikawa
- Department of Life Science, Himeji Institute of Technology, Kamighori Ako, Hyogo 678-1297, Japan.
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Gennis RB. Some recent contributions of FTIR difference spectroscopy to the study of cytochrome oxidase1. FEBS Lett 2003; 555:2-7. [PMID: 14630310 DOI: 10.1016/s0014-5793(03)01150-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Robert B Gennis
- Department of Biochemistry, University of Illinois, 600 South Mathews Street, Urbana, IL 61801, USA.
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