1
|
Gladyshev GV, Zharova TV, Kareyeva AV, Grivennikova VG. Proton-translocating NADH:ubiquinone oxidoreductase of Paracoccus denitrificans plasma membranes catalyzes FMN-independent reverse electron transfer to hexaammineruthenium (III). BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2023; 1864:148963. [PMID: 36842539 DOI: 10.1016/j.bbabio.2023.148963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/10/2023] [Accepted: 02/19/2023] [Indexed: 02/27/2023]
Abstract
NADH-OH, the specific inhibitor of NADH-binding site of the mammalian complex I, is shown to completely block FMN-dependent reactions of P. denitrificans enzyme in plasma membrane vesicles: NADH oxidation (in a competitive manner with Ki of 1 nM) as well as reduction of pyridine nucleotides, ferricyanide and oxygen in the reverse electron transfer. In contrast to these activities, the reverse electron transfer to hexaammineruthenium (III) catalyzed by plasma membrane vesicles is insensitive to NADH-OH. To explain these results, we hypothesize the existence of a non-FMN redox group of P. denitrificans complex I that is capable of reducing hexaammineruthenium (III), which is corroborated by the complex kinetics of NADH: hexaammineruthenium (III)-reductase activity, catalyzed by this enzyme. A new assay procedure for measuring succinate-driven reverse electron transfer catalyzed by P. denitrificans complex I to hexaammineruthenium (III) is proposed.
Collapse
Affiliation(s)
- Grigory V Gladyshev
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119991, Russian Federation.
| | - Tatyana V Zharova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119991, Russian Federation
| | - Alexandra V Kareyeva
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119991, Russian Federation
| | - Vera G Grivennikova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119991, Russian Federation
| |
Collapse
|
2
|
Yoval-Sánchez B, Ansari F, James J, Niatsetskaya Z, Sosunov S, Filipenko P, Tikhonova IG, Ten V, Wittig I, Rafikov R, Galkin A. Redox-dependent loss of flavin by mitochondria complex I is different in brain and heart. Redox Biol 2022; 51:102258. [PMID: 35189550 PMCID: PMC8861397 DOI: 10.1016/j.redox.2022.102258] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/26/2022] [Accepted: 01/31/2022] [Indexed: 12/14/2022] Open
Abstract
Pathologies associated with tissue ischemia/reperfusion (I/R) in highly metabolizing organs such as the brain and heart are leading causes of death and disability in humans. Molecular mechanisms underlying mitochondrial dysfunction during acute injury in I/R are tissue-specific, but their details are not completely understood. A metabolic shift and accumulation of substrates of reverse electron transfer (RET) such as succinate are observed in tissue ischemia, making mitochondrial complex I of the respiratory chain (NADH:ubiquinone oxidoreductase) the most vulnerable enzyme to the following reperfusion. It has been shown that brain complex I is predisposed to losing its flavin mononucleotide (FMN) cofactor when maintained in the reduced state in conditions of RET both in vitro and in vivo. Here we investigated the process of redox-dependent dissociation of FMN from mitochondrial complex I in brain and heart mitochondria. In contrast to the brain enzyme, cardiac complex I does not lose FMN when reduced in RET conditions. We proposed that the different kinetics of FMN loss during RET is due to the presence of brain-specific long 50 kDa isoform of the NDUFV3 subunit of complex I, which is absent in the heart where only the canonical 10 kDa short isoform is found. Our simulation studies suggest that the long NDUFV3 isoform can reach toward the FMN binding pocket and affect the nucleotide affinity to the apoenzyme. For the first time, we demonstrated a potential functional role of tissue-specific isoforms of complex I, providing the distinct molecular mechanism of I/R-induced mitochondrial impairment in cardiac and cerebral tissues. By combining functional studies of intact complex I and molecular structure simulations, we defined the critical difference between the brain and heart enzyme and suggested insights into the redox-dependent inactivation mechanisms of complex I during I/R injury in both tissues.
Collapse
Affiliation(s)
- Belem Yoval-Sánchez
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY, 10065, USA
| | - Fariha Ansari
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY, 10065, USA
| | - Joel James
- Division of Endocrinology, Department of Medicine, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Zoya Niatsetskaya
- Department of Pediatrics, Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ, 08901, USA
| | - Sergey Sosunov
- Department of Pediatrics, Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ, 08901, USA
| | - Peter Filipenko
- Department of Biochemistry, Weill Cornell Medical College, Cornell University, New York, NY, 10021, USA
| | - Irina G. Tikhonova
- School of Pharmacy, Medical Biology, Centre, Queen's University Belfast, Belfast, BT9 7BL, United Kingdom
| | - Vadim Ten
- Department of Pediatrics, Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ, 08901, USA
| | - Ilka Wittig
- Functional Proteomics, Cardiovascular Physiology, Goethe University, 60590, Frankfurt am Main, Germany,German Center for Cardiovascular Research (DZHK), Partner site RheinMain, Frankfurt, Germany
| | - Ruslan Rafikov
- Division of Endocrinology, Department of Medicine, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Alexander Galkin
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY, 10065, USA,Corresponding author.
| |
Collapse
|
3
|
Melin F, Hellwig P. Redox Properties of the Membrane Proteins from the Respiratory Chain. Chem Rev 2020; 120:10244-10297. [DOI: 10.1021/acs.chemrev.0c00249] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Frederic Melin
- Chimie de la Matière Complexe UMR 7140, Laboratoire de Bioelectrochimie et Spectroscopie, CNRS-Université de Strasbourg, 1 rue Blaise Pascal, 67070 Strasbourg, France
| | - Petra Hellwig
- Chimie de la Matière Complexe UMR 7140, Laboratoire de Bioelectrochimie et Spectroscopie, CNRS-Université de Strasbourg, 1 rue Blaise Pascal, 67070 Strasbourg, France
| |
Collapse
|
4
|
Santos Seica AF, Schimpf J, Friedrich T, Hellwig P. Visualizing the movement of the amphipathic helix in the respiratory complex I using a nitrile infrared probe and SEIRAS. FEBS Lett 2019; 594:491-496. [PMID: 31556114 DOI: 10.1002/1873-3468.13620] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 09/20/2019] [Accepted: 09/23/2019] [Indexed: 01/22/2023]
Abstract
Conformational movements play an important role in enzyme catalysis. Respiratory complex I, an L-shaped enzyme, connects electron transfer from NADH to ubiquinone in its peripheral arm with proton translocation through its membrane arm by a coupling mechanism still under debate. The amphipathic helix across the membrane arm represents a unique structural feature. Here, we demonstrate a new way to study conformational changes by introducing a small and highly flexible nitrile infrared (IR) label to this helix to visualize movement with surface-enhanced IR absorption spectroscopy. We find that labeled residues K551CL and Y590CL move to a more hydrophobic environment upon NADH reduction of the enzyme, likely as a response to the reorganization of the antiporter-like subunits in the membrane arm.
Collapse
Affiliation(s)
- Ana Filipa Santos Seica
- Laboratoire de Bioélectrochimie et Spectroscopie, UMR 7140, CMC, Université de Strasbourg CNRS, France
| | - Johannes Schimpf
- Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Germany
| | | | - Petra Hellwig
- Laboratoire de Bioélectrochimie et Spectroscopie, UMR 7140, CMC, Université de Strasbourg CNRS, France.,University of Strasbourg Institute for Advanced Studies (USIAS), France
| |
Collapse
|
5
|
Frolova MS, Marchenkov VV, Vekshin NL. Disruption of flavin homeostasis in isolated rat liver mitochondria. Biochem Biophys Res Commun 2019; 516:1211-1215. [PMID: 31300198 DOI: 10.1016/j.bbrc.2019.07.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 07/05/2019] [Indexed: 12/16/2022]
Abstract
It has been shown that spontaneous release of non-covalent flavins (from flavoenzymes) begins after isolation of mitochondria from rat liver, which is hydrolyzed to riboflavin. This process is stopped by 1 mM EDTA in the incubation medium. In the presence of NADH, deflavinization of flavoproteins leads to formation of superoxide by at least of three processes. The first of these occurs in complex I as a result of the spontaneous release of FMN from the active center. This process is inhibited by adenosine and guanosine phosphates, as well as NAD, but amplified by nicotinamide. The second process is associated with enzymatic hydrolysis of FAD and FMN to riboflavin; it is blocked by EDTA, AMP, NA, NAD. The third process is associated with non-enzymatic hydrolysis of FAD by iron ions in matrix; it is blocked by EDTA and AMP.
Collapse
Affiliation(s)
- M S Frolova
- Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Russia.
| | - V V Marchenkov
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Russia
| | - N L Vekshin
- Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Russia
| |
Collapse
|
6
|
Stepanova A, Kahl A, Konrad C, Ten V, Starkov AS, Galkin A. Reverse electron transfer results in a loss of flavin from mitochondrial complex I: Potential mechanism for brain ischemia reperfusion injury. J Cereb Blood Flow Metab 2017; 37:3649-3658. [PMID: 28914132 PMCID: PMC5718331 DOI: 10.1177/0271678x17730242] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Ischemic stroke is one of the most prevalent sources of disability in the world. The major brain tissue damage takes place upon the reperfusion of ischemic tissue. Energy failure due to alterations in mitochondrial metabolism and elevated production of reactive oxygen species (ROS) is one of the main causes of brain ischemia-reperfusion (IR) damage. Ischemia resulted in the accumulation of succinate in tissues, which favors the process of reverse electron transfer (RET) when a fraction of electrons derived from succinate is directed to mitochondrial complex I for the reduction of matrix NAD+. We demonstrate that in intact brain mitochondria oxidizing succinate, complex I became damaged and was not able to contribute to the physiological respiration. This process is associated with a decline in ROS release and a dissociation of the enzyme's flavin. This previously undescribed phenomenon represents the major molecular mechanism of injury in stroke and induction of oxidative stress after reperfusion. We also demonstrate that the origin of ROS during RET is flavin of mitochondrial complex I. Our study highlights a novel target for neuroprotection against IR brain injury and provides a sensitive biochemical marker for this process.
Collapse
Affiliation(s)
- Anna Stepanova
- 1 School of Biological Sciences, Medical Biology Centre, 1596 Queen's University Belfast , Belfast, UK.,2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Anja Kahl
- 2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Csaba Konrad
- 2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Vadim Ten
- 3 Department of Pediatrics, Columbia University, New York, NY, USA
| | - Anatoly S Starkov
- 2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Alexander Galkin
- 1 School of Biological Sciences, Medical Biology Centre, 1596 Queen's University Belfast , Belfast, UK.,2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| |
Collapse
|
7
|
Papa S, Capitanio G, Papa F. The mechanism of coupling between oxido-reduction and proton translocation in respiratory chain enzymes. Biol Rev Camb Philos Soc 2017. [DOI: 10.1111/brv.12347] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Sergio Papa
- Department of Basic Medical Sciences, Neurosciences and Sense Organs (BMSNSO), Section of Medical Biochemistry; University of Bari ‘Aldo Moro’; Piazza G. Cesare 11 70124 Bari Italy
- Institute of Biomembranes and Bioenergetics; National Research Council at BMSNSO; Piazza G. Cesare 11 70124 Bari Italy
| | - Giuseppe Capitanio
- Department of Basic Medical Sciences, Neurosciences and Sense Organs (BMSNSO), Section of Medical Biochemistry; University of Bari ‘Aldo Moro’; Piazza G. Cesare 11 70124 Bari Italy
| | - Francesco Papa
- Department of Basic Medical Sciences, Neurosciences and Sense Organs (BMSNSO), Section of Medical Biochemistry; University of Bari ‘Aldo Moro’; Piazza G. Cesare 11 70124 Bari Italy
| |
Collapse
|
8
|
Tursun A, Zhu S, Vik SB. Probing the proton channels in subunit N of Complex I from Escherichia coli through intra-subunit cross-linking. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1840-1848. [PMID: 27632419 DOI: 10.1016/j.bbabio.2016.09.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 08/19/2016] [Accepted: 09/09/2016] [Indexed: 10/21/2022]
Abstract
Respiratory Complex I appears to have 4 sites for proton translocation, which are coupled to the oxidation of NADH and reduction of coenzyme Q. The proton pathways are thought to be made of offset half-channels that connect to the membrane surfaces, and are connected by a horizontal path through the center of the membrane. In this study of the enzyme from Escherichia coli, subunit N, containing one of the sites, was targeted. Pairs of cysteine residues were introduced into neighboring α-helices along the proposed proton pathways. In an effort to constrain conformational changes that might occur during proton translocation, we attempted to form disulfide bonds or methanethiosulfonate bridges between two engineered cysteine residues. Cysteine modification was inferred by the inability of PEG-maleimide to shift the electrophoretic mobility of subunit N, which will occur upon reaction with free sulfhydryl groups. After the cross-linking treatment, NADH oxidase and NADH-driven proton translocation were measured. Ten different pairs of cysteine residues showed evidence of cross-linking. The most significant loss of enzyme activity was seen for residues near the essential Lys 395. This residue is positioned between the proposed proton half-channel to the periplasm and the horizontal connection through subunit N, and is also near the essential Glu 144 of subunit M. The results suggest important conformational changes in this region for the delivery of protons to the periplasm, or for coupling the actions of subunit N to subunit M.
Collapse
Affiliation(s)
- Ablat Tursun
- Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275-0376, USA
| | - Shaotong Zhu
- Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275-0376, USA
| | - Steven B Vik
- Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275-0376, USA.
| |
Collapse
|
9
|
Holt PJ, Efremov RG, Nakamaru-Ogiso E, Sazanov LA. Reversible FMN dissociation from Escherichia coli respiratory complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1777-1785. [PMID: 27555334 DOI: 10.1016/j.bbabio.2016.08.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 08/04/2016] [Accepted: 08/17/2016] [Indexed: 12/13/2022]
Abstract
Respiratory complex I transfers electrons from NADH to quinone, utilizing the reaction energy to translocate protons across the membrane. It is a key enzyme of the respiratory chain of many prokaryotic and most eukaryotic organisms. The reversible NADH oxidation reaction is facilitated in complex I by non-covalently bound flavin mononucleotide (FMN). Here we report that the catalytic activity of E. coli complex I with artificial electron acceptors potassium ferricyanide (FeCy) and hexaamineruthenium (HAR) is significantly inhibited in the enzyme pre-reduced by NADH. Further, we demonstrate that the inhibition is caused by reversible dissociation of FMN. The binding constant (Kd) for FMN increases from the femto- or picomolar range in oxidized complex I to the nanomolar range in the NADH reduced enzyme, with an FMN dissociation time constant of ~5s. The oxidation state of complex I, rather than that of FMN, proved critical to the dissociation. Such dissociation is not observed with the T. thermophilus enzyme and our analysis suggests that the difference may be due to the unusually high redox potential of Fe-S cluster N1a in E. coli. It is possible that the enzyme attenuates ROS production in vivo by releasing FMN under highly reducing conditions.
Collapse
Affiliation(s)
- Peter J Holt
- MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | - Rouslan G Efremov
- Structural Biology Research Center, VIB, 1050 Brussels, Belgium; Structural Biology Brussels, Vrije Universiteit Brussel (VUB), 1050 Brussels, Belgium
| | - Eiko Nakamaru-Ogiso
- Johnson Research Foundation, Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6059, United States
| | - Leonid A Sazanov
- Institute of Science and Technology Austria, Am Campus 1, A-3400 Klosterneuburg, Austria.
| |
Collapse
|
10
|
Sulfo-SMCC Prevents Annealing of Taxol-Stabilized Microtubules In Vitro. PLoS One 2016; 11:e0161623. [PMID: 27561096 PMCID: PMC4999061 DOI: 10.1371/journal.pone.0161623] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 08/09/2016] [Indexed: 11/21/2022] Open
Abstract
Microtubule structure and functions have been widely studied in vitro and in cells. Research has shown that cysteines on tubulin play a crucial role in the polymerization of microtubules. Here, we show that blocking sulfhydryl groups of cysteines in taxol-stabilized polymerized microtubules with a commonly used chemical crosslinker prevents temporal end-to-end annealing of microtubules in vitro. This can dramatically affect the length distribution of the microtubules. The crosslinker sulfosuccinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate, sulfo-SMCC, consists of a maleimide and an N-hydroxysuccinimide ester group to bind to sulfhydryl groups and primary amines, respectively. Interestingly, addition of a maleimide dye alone does not show the same interference with annealing in stabilized microtubules. This study shows that the sulfhydryl groups of cysteines of tubulin that are vital for the polymerization are also important for the subsequent annealing of microtubules.
Collapse
|
11
|
Hanazono Y, Takeda K, Miki K. Characterization of the Nqo5 subunit of bacterial complex I in the isolated state. FEBS Open Bio 2016; 6:687-95. [PMID: 27398308 PMCID: PMC4932448 DOI: 10.1002/2211-5463.12070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 04/12/2016] [Accepted: 04/14/2016] [Indexed: 11/09/2022] Open
Abstract
The subunits that comprise bacterial complex I (NADH:ubiquinone oxidoreductase) are also found in more complicated mitochondrial enzymes in eukaryotic organisms. Although the Nqo5 subunit is one of these conserved components and important for the formation of complex, it has been little studied. Here, we report structure analyses of isolated Nqo5 from Thermus thermophilus. Biochemical studies indicated that the C-terminal region following the 30-Kd subunit motif is disordered in the isolated state, while the remaining portion is already folded. Crystallographic studies of a trypsin-resistant fragment revealed detailed structural differences in the folded domain between the isolated and complexed states.
Collapse
Affiliation(s)
- Yuya Hanazono
- Department of Chemistry Graduate School of Science Kyoto University Sakyo-ku Kyoto Japan
| | - Kazuki Takeda
- Department of Chemistry Graduate School of Science Kyoto University Sakyo-ku Kyoto Japan; RIKEN SPring-8 Center at Harima Institute Sayo Hyogo Japan
| | - Kunio Miki
- Department of Chemistry Graduate School of Science Kyoto University Sakyo-ku Kyoto Japan; RIKEN SPring-8 Center at Harima Institute Sayo Hyogo Japan
| |
Collapse
|
12
|
Berrisford JM, Baradaran R, Sazanov LA. Structure of bacterial respiratory complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:892-901. [PMID: 26807915 DOI: 10.1016/j.bbabio.2016.01.012] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 01/18/2016] [Accepted: 01/20/2016] [Indexed: 12/23/2022]
Abstract
Complex I (NADH:ubiquinone oxidoreductase) plays a central role in cellular energy production, coupling electron transfer between NADH and quinone to proton translocation. It is the largest protein assembly of respiratory chains and one of the most elaborate redox membrane proteins known. Bacterial enzyme is about half the size of mitochondrial and thus provides its important "minimal" model. Dysfunction of mitochondrial complex I is implicated in many human neurodegenerative diseases. The L-shaped complex consists of a hydrophilic arm, where electron transfer occurs, and a membrane arm, where proton translocation takes place. We have solved the crystal structures of the hydrophilic domain of complex I from Thermus thermophilus, the membrane domain from Escherichia coli and recently of the intact, entire complex I from T. thermophilus (536 kDa, 16 subunits, 9 iron-sulphur clusters, 64 transmembrane helices). The 95Å long electron transfer pathway through the enzyme proceeds from the primary electron acceptor flavin mononucleotide through seven conserved Fe-S clusters to the unusual elongated quinone-binding site at the interface with the membrane domain. Four putative proton translocation channels are found in the membrane domain, all linked by the central flexible axis containing charged residues. The redox energy of electron transfer is coupled to proton translocation by the as yet undefined mechanism proposed to involve long-range conformational changes. This article is part of a Special Issue entitled Respiratory complex I, edited by Volker Zickermann and Ulrich Brandt.
Collapse
Affiliation(s)
| | - Rozbeh Baradaran
- Memorial Sloan-Kettering Cancer Center, 430 E 67th Street, NY 10065, USA
| | - Leonid A Sazanov
- Institute of Science and Technology Austria (IST Austria), Am Campus 1, 3400 Klosterneuburg, Austria.
| |
Collapse
|
13
|
Sazanov LA. A giant molecular proton pump: structure and mechanism of respiratory complex I. Nat Rev Mol Cell Biol 2015; 16:375-88. [PMID: 25991374 DOI: 10.1038/nrm3997] [Citation(s) in RCA: 314] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mitochondrial respiratory chain, also known as the electron transport chain (ETC), is crucial to life, and energy production in the form of ATP is the main mitochondrial function. Three proton-translocating enzymes of the ETC, namely complexes I, III and IV, generate proton motive force, which in turn drives ATP synthase (complex V). The atomic structures and basic mechanisms of most respiratory complexes have previously been established, with the exception of complex I, the largest complex in the ETC. Recently, the crystal structure of the entire complex I was solved using a bacterial enzyme. The structure provided novel insights into the core architecture of the complex, the electron transfer and proton translocation pathways, as well as the mechanism that couples these two processes.
Collapse
Affiliation(s)
- Leonid A Sazanov
- Institute of Science and Technology Austria, 3400 Klosterneuburg, Austria
| |
Collapse
|
14
|
Murai M, Miyoshi H. Chemical modifications of respiratory complex I for structural and functional studies. J Bioenerg Biomembr 2014; 46:313-21. [DOI: 10.1007/s10863-014-9562-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 06/26/2014] [Indexed: 01/07/2023]
|
15
|
Babot M, Birch A, Labarbuta P, Galkin A. Characterisation of the active/de-active transition of mitochondrial complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1083-92. [PMID: 24569053 PMCID: PMC4331042 DOI: 10.1016/j.bbabio.2014.02.018] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 02/14/2014] [Accepted: 02/17/2014] [Indexed: 12/12/2022]
Abstract
Oxidation of NADH in the mitochondrial matrix of aerobic cells is catalysed by mitochondrial complex I. The regulation of this mitochondrial enzyme is not completely understood. An interesting characteristic of complex I from some organisms is the ability to adopt two distinct states: the so-called catalytically active (A) and the de-active, dormant state (D). The A-form in situ can undergo de-activation when the activity of the respiratory chain is limited (i.e. in the absence of oxygen). The mechanisms and driving force behind the A/D transition of the enzyme are currently unknown, but several subunits are most likely involved in the conformational rearrangements: the accessory subunit 39 kDa (NDUFA9) and the mitochondrially encoded subunits, ND3 and ND1. These three subunits are located in the region of the quinone binding site. The A/D transition could represent an intrinsic mechanism which provides a fast response of the mitochondrial respiratory chain to oxygen deprivation. The physiological role of the accumulation of the D-form in anoxia is most probably to protect mitochondria from ROS generation due to the rapid burst of respiration following reoxygenation. The de-activation rate varies in different tissues and can be modulated by the temperature, the presence of free fatty acids and divalent cations, the NAD+/NADH ratio in the matrix, the presence of nitric oxide and oxygen availability. Cysteine-39 of the ND3 subunit, exposed in the D-form, is susceptible to covalent modification by nitrosothiols, ROS and RNS. The D-form in situ could react with natural effectors in mitochondria or with pharmacological agents. Therefore the modulation of the re-activation rate of complex I could be a way to ameliorate the ischaemia/reperfusion damage. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference. Guest Editors: Manuela Pereira and Miguel Teixeira. The potential mechanism of complex I A/D transition is discussed. An —SH group exposed in the D-form is susceptible to covalent modification. The role of A/D transition in tissue response to ischaemia is proposed.
Collapse
Affiliation(s)
- Marion Babot
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Amanda Birch
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Paola Labarbuta
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Alexander Galkin
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
| |
Collapse
|
16
|
Babot M, Labarbuta P, Birch A, Kee S, Fuszard M, Botting CH, Wittig I, Heide H, Galkin A. ND3, ND1 and 39kDa subunits are more exposed in the de-active form of bovine mitochondrial complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:929-39. [PMID: 24560811 PMCID: PMC4331043 DOI: 10.1016/j.bbabio.2014.02.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 01/20/2014] [Accepted: 02/12/2014] [Indexed: 12/12/2022]
Abstract
An intriguing feature of mitochondrial complex I from several species is the so-called A/D transition, whereby the idle enzyme spontaneously converts from the active (A) form to the de-active (D) form. The A/D transition plays an important role in tissue response to the lack of oxygen and hypoxic deactivation of the enzyme is one of the key regulatory events that occur in mitochondria during ischaemia. We demonstrate for the first time that the A/D conformational change of complex I does not affect the macromolecular organisation of supercomplexes in vitro as revealed by two types of native electrophoresis. Cysteine 39 of the mitochondrially-encoded ND3 subunit is known to become exposed upon de-activation. Here we show that even if complex I is a constituent of the I + III2 + IV (S1) supercomplex, cysteine 39 is accessible for chemical modification in only the D-form. Using lysine-specific fluorescent labelling and a DIGE-like approach we further identified two new subunits involved in structural rearrangements during the A/D transition: ND1 (MT-ND1) and 39 kDa (NDUFA9). These results clearly show that structural rearrangements during de-activation of complex I include several subunits located at the junction between hydrophilic and hydrophobic domains, in the region of the quinone binding site. De-activation of mitochondrial complex I results in concerted structural rearrangement of membrane subunits which leads to the disruption of the sealed quinone chamber required for catalytic turnover. Supercomplex composition is not affected by mitochondrial complex I conformation. The D-form of complex I is selectively inhibited by tyrosine-reactive reagents. ND3, ND1 & 39 kDa subunits become exposed upon deactivation of complex I.
Collapse
Affiliation(s)
- Marion Babot
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Paola Labarbuta
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Amanda Birch
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Sara Kee
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Matthew Fuszard
- School of Chemistry, Biomedical Sciences Research Complex, BMS Annexe, University of St. Andrews, KY16 9ST, UK
| | - Catherine H Botting
- School of Chemistry, Biomedical Sciences Research Complex, BMS Annexe, University of St. Andrews, KY16 9ST, UK
| | - Ilka Wittig
- Functional Proteomics, SFB Core Unit, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Heinrich Heide
- Functional Proteomics, SFB Core Unit, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Alexander Galkin
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
| |
Collapse
|
17
|
Verkhovskaya M, Wikström M. Oxidoreduction properties of bound ubiquinone in Complex I from Escherichia coli. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1837:246-50. [PMID: 24216024 DOI: 10.1016/j.bbabio.2013.11.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 10/31/2013] [Accepted: 11/04/2013] [Indexed: 12/12/2022]
Abstract
The exploration of the redox chemistry of bound ubiquinone during catalysis is a prerequisite for the understanding of the mechanism by which Complex I (nicotinamide adenine dinucleotide (NADH):ubiquinone oxidoreductase) transduces redox energy into an electrochemical proton gradient. Studies of redox dependent changes in the spectrum of Complex I from Escherichia coli in the mid- and near-ultraviolet (UV) and visible areas were performed to identify the spectral contribution, and to determine the redox properties, of the tightly bound ubiquinone. A very low midpoint redox potential (<-300mV) was found for the bound ubiquinone, more than 400mV lower than when dissolved in a phospholipid membrane. This thermodynamic property of bound ubiquinone has important implications for the mechanism by which Complex I catalyzes proton translocation.
Collapse
Affiliation(s)
- Marina Verkhovskaya
- Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, PO Box 65 (Viikinkaari 1), FIN-00014 Helsinki, Finland.
| | - Mårten Wikström
- Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, PO Box 65 (Viikinkaari 1), FIN-00014 Helsinki, Finland
| |
Collapse
|
18
|
Narayanan M, Gabrieli DJ, Leung SA, Elguindy MM, Glaser CA, Saju N, Sinha SC, Nakamaru-Ogiso E. Semiquinone and cluster N6 signals in His-tagged proton-translocating NADH:ubiquinone oxidoreductase (complex I) from Escherichia coli. J Biol Chem 2013; 288:14310-14319. [PMID: 23543743 DOI: 10.1074/jbc.m113.467803] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
NADH:ubiquinone oxidoreductase (complex I) pumps protons across the membrane using downhill redox energy. The Escherichia coli complex I consists of 13 different subunits named NuoA-N coded by the nuo operon. Due to the low abundance of the protein and some difficulty with the genetic manipulation of its large ~15-kb operon, purification of E. coli complex I has been technically challenging. Here, we generated a new strain in which a polyhistidine sequence was inserted upstream of nuoE in the operon. This allowed us to prepare large amounts of highly pure and active complex I by efficient affinity purification. The purified complex I contained 0.94 ± 0.1 mol of FMN, 29.0 ± 0.37 mol of iron, and 1.99 ± 0.07 mol of ubiquinone/1 mol of complex I. The extinction coefficient of isolated complex I was 495 mM(-1) cm(-1) at 274 nm and 50.3 mM(-1) cm(-1) at 410 nm. NADH:ferricyanide activity was 219 ± 9.7 μmol/min/mg by using HEPES-Bis-Tris propane, pH 7.5. Detailed EPR analyses revealed two additional iron-sulfur cluster signals, N6a and N6b, in addition to previously assigned signals. Furthermore, we found small but significant semiquinone signal(s), which have been reported only for bovine complex I. The line width was ~12 G, indicating its neutral semiquinone form. More than 90% of the semiquinone signal originated from the single entity with P½ (half-saturation power level) = 1.85 milliwatts. The semiquinone signal(s) decreased by 60% when with asimicin, a potent complex I inhibitor. The functional role of semiquinone and the EPR assignment of clusters N6a/N6b are discussed.
Collapse
Affiliation(s)
- Madhavan Narayanan
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - David J Gabrieli
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Steven A Leung
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Mahmoud M Elguindy
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Carl A Glaser
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Nitha Saju
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Subhash C Sinha
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037
| | - Eiko Nakamaru-Ogiso
- Johnson Research Foundation, Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
| |
Collapse
|
19
|
Grivennikova VG, Vinogradov AD. Partitioning of superoxide and hydrogen peroxide production by mitochondrial respiratory complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:446-54. [PMID: 23313413 DOI: 10.1016/j.bbabio.2013.01.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 12/24/2012] [Accepted: 01/02/2013] [Indexed: 10/27/2022]
Abstract
Membrane-bound respiratory complex I in inside-out submitochondrial particles (SMP) catalyzes both superoxide and hydrogen peroxide formation in NADH- and/or succinate-supported reactions. At optimal NADH concentration (50μM), the complex I-mediated process results in a formation of two superoxide anions and H(2)O(2) as the reaction products in approximately 0.7 ratio. Almost the same ratio is found for purified complex I (0.6) and for the aerobic succinate-supported reverse electron transfer reaction. Superoxide production is depressed at high, more physiologically relevant NADH concentrations, whereas hydrogen peroxide formation is insensitive to the elevated level of NADH. The rates of H(2)O(2) formation at variable NAD(+)/NADH ratios satisfactorily fit the Nernst equation for a single reactive two-electron donor component equilibrated with ambient midpoint redox potential of -347mV (0.13 NAD(+)/NADH ratio, pH 8.0). Half-maximal superoxide production rate proceeds at significantly higher NAD(+)/NADH ratio (0.33). Guanidine strongly stimulates NADH-supported hydrogen peroxide and superoxide production at any NADH concentration and activates NADH:ferricyanide and inhibits NADH:hexaammineruthenium (III) reductase activities while showing no effects on NADH oxidase of SMP. In the low range of NADH concentration, superoxide production rate shows a simple hyperbolic dependence on NADH with apparent K(m)(NADH) of 0.5μM, whereas sigmoidal dependence of hydrogen peroxide production is seen with half-maximal rate at 25μM NADH. We interpret the data as to suggest that at least two sites participate in complex I-mediated ROS generation: FMNH(-) that produces hydrogen peroxide, and an iron-sulfur center (likely N-2) that produces superoxide anion.
Collapse
Affiliation(s)
- Vera G Grivennikova
- Department of Biochemistry, Moscow State University, Moscow, Russian Federation
| | | |
Collapse
|
20
|
Batista AP, Marreiros BC, Pereira MM. The role of proton and sodium ions in energy transduction by respiratory complex I. IUBMB Life 2012; 64:492-8. [PMID: 22576956 DOI: 10.1002/iub.1050] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 04/17/2012] [Indexed: 11/08/2022]
Abstract
Respiratory complex I plays a central role in energy transduction. It catalyzes the oxidation of NADH and the reduction of quinone, coupled to cation translocation across the membrane, thereby establishing an electrochemical potential. For more than half a century, data on complex I has been gathered, including recently determined crystal structures, yet complex I is the least understood complex of the respiratory chain. The mechanisms of quinone reduction, charge translocation and their coupling are still unknown. The H(+) is accepted to be the coupling ion of the system; however, Na(+) has also been suggested to perform such a role. In this article, we address the relation of those two ions with complex I and refer ion pump and Na(+)/H(+) antiporter as possible transport mechanisms of the system. We put forward a hypothesis to explain some apparently contradictory data on the nature of the coupling ion, and we revisit the role of H(+) and Na(+) cycles in the overall bioenergetics of the cell.
Collapse
Affiliation(s)
- Ana P Batista
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da Republica EAN, 2780-157 Oeiras, Portugal
| | | | | |
Collapse
|
21
|
Torres-Bacete J, Sinha PK, Matsuno-Yagi A, Yagi T. Structural contribution of C-terminal segments of NuoL (ND5) and NuoM (ND4) subunits of complex I from Escherichia coli. J Biol Chem 2011; 286:34007-14. [PMID: 21835926 DOI: 10.1074/jbc.m111.260968] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The proton-translocating NADH-quinone oxidoreductase (complex I/NDH-1) is a multisubunit enzymatic complex. It has a characteristic L-shaped form with two domains, a hydrophilic peripheral domain and a hydrophobic membrane domain. The membrane domain contains three antiporter-like subunits (NuoL, NuoM, and NuoN, Escherichia coli naming) that are considered to be involved in the proton translocation. Deletion of either NuoL or NuoM resulted in an incomplete assembly of NDH-1 and a total loss of the NADH-quinone oxidoreductase activity. We have truncated the C terminus segments of NuoM and NuoL by introducing STOP codons at different locations using site-directed mutagenesis of chromosomal DNA. Our results suggest an important structural role for the C-terminal segments of both subunits. The data further advocate that the elimination of the last transmembrane helix (TM14) of NuoM and the TM16 (at least C-terminal seven residues) or together with the HL helix and the TM15 of the NuoL subunit lead to reduced stability of the membrane arm and therefore of the whole NDH-1 complex. A region of NuoL critical for stability of NDH-1 architecture has been discussed.
Collapse
Affiliation(s)
- Jesus Torres-Bacete
- Department of Molecular and Experimental Medicine, MEM-256, The Scripps Research Institute, La Jolla, California 92037, USA
| | | | | | | |
Collapse
|
22
|
Morina K, Schulte M, Hubrich F, Dörner K, Steimle S, Stolpe S, Friedrich T. Engineering the respiratory complex I to energy-converting NADPH:ubiquinone oxidoreductase. J Biol Chem 2011; 286:34627-34. [PMID: 21832062 DOI: 10.1074/jbc.m111.274571] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The respiratory complex I couples the electron transfer from NADH to ubiquinone with a translocation of protons across the membrane. Its nucleotide-binding site is made up of a unique Rossmann fold to accommodate the binding of the substrate NADH and of the primary electron acceptor flavin mononucleotide. Binding of NADH includes interactions of the hydroxyl groups of the adenosine ribose with a conserved glutamic acid residue. Structural analysis revealed that due to steric hindrance and electrostatic repulsion, this residue most likely prevents the binding of NADPH, which is a poor substrate of the complex. We produced several variants with mutations at this position exhibiting up to 200-fold enhanced catalytic efficiency with NADPH. The reaction of the variants with NAD(P)H is coupled with proton translocation in an inhibitor-sensitive manner. Thus, we have created an energy-converting NADPH:ubiquinone oxidoreductase, an activity so far not found in nature. Remarkably, the oxidation of NAD(P)H by the variants leads to an enhanced production of reactive oxygen species.
Collapse
Affiliation(s)
- Klaudia Morina
- Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität, 79104 Freiburg, Germany
| | | | | | | | | | | | | |
Collapse
|
23
|
Efremov RG, Sazanov LA. Respiratory complex I: 'steam engine' of the cell? Curr Opin Struct Biol 2011; 21:532-40. [PMID: 21831629 DOI: 10.1016/j.sbi.2011.07.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 06/01/2011] [Accepted: 07/07/2011] [Indexed: 12/19/2022]
Abstract
Complex I is the first enzyme of the respiratory chain and plays a central role in cellular energy production. It has been implicated in many human neurodegenerative diseases, as well as in ageing. One of the biggest membrane protein complexes, it is an L-shaped assembly consisting of hydrophilic and membrane domains. Previously, we have determined structures of the hydrophilic domain in several redox states. Last year was marked by fascinating breakthroughs in the understanding of the complete structure. We described the architecture of the membrane domain and of the entire bacterial complex I. X-ray analysis of the larger mitochondrial enzyme has also been published. The core subunits of the bacterial and mitochondrial enzymes have remarkably similar structures. The proposed mechanism of coupling between electron transfer and proton translocation involves long-range conformational changes, coordinated in part by a long α-helix, akin to the coupling rod of a steam engine.
Collapse
Affiliation(s)
- Rouslan G Efremov
- Medical Research Council Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | | |
Collapse
|
24
|
Murai M, Mashimo Y, Hirst J, Miyoshi H. Exploring interactions between the 49 kDa and ND1 subunits in mitochondrial NADH-ubiquinone oxidoreductase (complex I) by photoaffinity labeling. Biochemistry 2011; 50:6901-8. [PMID: 21721533 DOI: 10.1021/bi200883c] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quinazolines are strong inhibitors of NADH-ubiquinone oxidoreductase (complex I) from bovine heart mitochondria. Using a photoreactive quinazoline, [(125)I]AzQ, and bovine heart submitochondrial particles (SMPs), we demonstrated previously that [(125)I]AzQ binds at the interface of the 49 kDa and ND1 subunits in complex I; it labeled a site in the N-terminal (Asp41-Arg63) region of the 49 kDa subunit, suggesting that this region contacts the ND1 subunit [Murai, M., et al. (2009) Biochemistry 48, 688-698]. The labeled region of ND1 could not be identified because it is highly hydrophobic, and the SMPs did not yield sufficient amounts of labeled protein. Here, we describe how photoaffinity labeling of isolated complex I by [(125)I]AzQ yielded sufficient material for identification of the labeled region of the ND1 subunit. The inhibition of the isolated enzyme by AzQ is comparable to that of SMPs. Our results reveal that the labeled site in ND1 is between Asp199 and Lys262, mostly likely in the third matrix loop that connects the fifth and sixth transmembrane helices. Thus, our results reveal new information about the interface between the hydrophilic and hydrophobic domains of complex I, a region that is thought to be important for ubiquinone reduction and energy transduction.
Collapse
Affiliation(s)
- Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | | | | | | |
Collapse
|
25
|
Bhave DP, Han WG, Pazicni S, Penner-Hahn JE, Carroll KS, Noodleman L. Geometric and electrostatic study of the [4Fe-4S] cluster of adenosine-5'-phosphosulfate reductase from broken symmetry density functional calculations and extended X-ray absorption fine structure spectroscopy. Inorg Chem 2011; 50:6610-25. [PMID: 21678934 DOI: 10.1021/ic200446c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Adenosine-5'-phosphosulfate reductase (APSR) is an iron-sulfur protein that catalyzes the reduction of adenosine-5'-phosphosulfate (APS) to sulfite. APSR coordinates to a [4Fe-4S] cluster via a conserved CC-X(~80)-CXXC motif, and the cluster is essential for catalysis. Despite extensive functional, structural, and spectroscopic studies, the exact role of the iron-sulfur cluster in APS reduction remains unknown. To gain an understanding into the role of the cluster, density functional theory (DFT) analysis and extended X-ray fine structure spectroscopy (EXAFS) have been performed to reveal insights into the coordination, geometry, and electrostatics of the [4Fe-4S] cluster. X-ray absorption near-edge structure (XANES) data confirms that the cluster is in the [4Fe-4S](2+) state in both native and substrate-bound APSR while EXAFS data recorded at ~0.1 Å resolution indicates that there is no significant change in the structure of the [4Fe-4S] cluster between the native and substrate-bound forms of the protein. On the other hand, DFT calculations provide an insight into the subtle differences between the geometry of the cluster in the native and APS-bound forms of APSR. A comparison between models with and without the tandem cysteine pair coordination of the cluster suggests a role for the unique coordination in facilitating a compact geometric structure and "fine-tuning" the electronic structure to prevent reduction of the cluster. Further, calculations using models in which residue Lys144 is mutated to Ala confirm the finding that Lys144 serves as a crucial link in the interactions involving the [4Fe-4S] cluster and APS.
Collapse
Affiliation(s)
- Devayani P Bhave
- Chemical Biology Graduate Program, University of Michigan, Ann Arbor, Michigan 48109-2216, USA
| | | | | | | | | | | |
Collapse
|
26
|
Kinetics and regulation of mammalian NADH-ubiquinone oxidoreductase (Complex I). Biophys J 2010; 99:1426-36. [PMID: 20816054 DOI: 10.1016/j.bpj.2010.06.063] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 06/14/2010] [Accepted: 06/22/2010] [Indexed: 11/22/2022] Open
Abstract
NADH-ubiquinone oxidoreductase (Complex I, European Commission No. 1.6.5.3) is one of the respiratory complexes that generate the proton-motive force required for the synthesis of ATP in mitochondria. The catalytic mechanism of Complex I has not been well understood, due to the complicated structure of this enzyme. Here, we develop a kinetic model for Complex I that accounts for electron transfer from NADH to ubiquinone through protein-bound prosthetic groups, which is coupled to the translocation of protons across the inner mitochondrial membrane. The model is derived based on the tri-bi enzyme mechanism combined with a simple model of the conformational changes associated with proton transport. To study the catalytic mechanism, parameter values are estimated by analyzing kinetic data. The model is further validated by independent data sets from additional experiments, effectively explaining the effect of pH on enzyme activity. Results imply that matrix pH significantly affects the enzyme turnover processes. The overall kinetic analysis demonstrates a hybrid ping-pong rapid-equilibrium random bi-bi mechanism, consolidating the characteristics from previously reported kinetic mechanisms and data.
Collapse
|
27
|
Hielscher R, Friedrich T, Hellwig P. Far- and Mid-Infrared Spectroscopic Analysis of the Substrate-Induced Structural Dynamics of Respiratory Complex I. Chemphyschem 2010; 12:217-24. [DOI: 10.1002/cphc.201000688] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2010] [Revised: 10/22/2010] [Indexed: 11/07/2022]
|
28
|
Yip CY, Harbour ME, Jayawardena K, Fearnley IM, Sazanov LA. Evolution of respiratory complex I: "supernumerary" subunits are present in the alpha-proteobacterial enzyme. J Biol Chem 2010; 286:5023-33. [PMID: 21115482 DOI: 10.1074/jbc.m110.194993] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Modern α-proteobacteria are thought to be closely related to the ancient symbiont of eukaryotes, an ancestor of mitochondria. Respiratory complex I from α-proteobacteria and mitochondria is well conserved at the level of the 14 "core" subunits, consistent with that notion. Mitochondrial complex I contains the core subunits, present in all species, and up to 31 "supernumerary" subunits, generally thought to have originated only within eukaryotic lineages. However, the full protein composition of an α-proteobacterial complex I has not been established previously. Here, we report the first purification and characterization of complex I from the α-proteobacterium Paracoccus denitrificans. Single particle electron microscopy shows that the complex has a well defined L-shape. Unexpectedly, in addition to the 14 core subunits, the enzyme also contains homologues of three supernumerary mitochondrial subunits as follows: B17.2, AQDQ/18, and 13 kDa (bovine nomenclature). This finding suggests that evolution of complex I via addition of supernumerary or "accessory" subunits started before the original endosymbiotic event that led to the creation of the eukaryotic cell. It also provides further confirmation that α-proteobacteria are the closest extant relatives of mitochondria.
Collapse
Affiliation(s)
- Chui-ying Yip
- Medical Research Council Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, United Kingdom
| | | | | | | | | |
Collapse
|
29
|
Gustavsson T, Trane M, Moparthi VK, Miklovyte E, Moparthi L, Górecki K, Leiding T, Arsköld SP, Hägerhäll C. A cytochrome c fusion protein domain for convenient detection, quantification, and enhanced production of membrane proteins in Escherichia coli--expression and characterization of cytochrome-tagged Complex I subunits. Protein Sci 2010; 19:1445-60. [PMID: 20509166 DOI: 10.1002/pro.424] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Overproduction of membrane proteins can be a cumbersome task, particularly if high yields are desirable. NADH:quinone oxidoreductase (Complex I) contains several very large membrane-spanning protein subunits that hitherto have been impossible to express individually in any appreciable amounts in Escherichia coli. The polypeptides contain no prosthetic groups and are poorly antigenic, making optimization of protein production a challenging task. In this work, the C-terminal ends of the Complex I subunits NuoH, NuoL, NuoM, and NuoN from E. coli Complex I and the bona fide antiporters MrpA and MrpD were genetically fused to the cytochrome c domain of Bacillus subtilis cytochrome c(550). Compared with other available fusion-protein tagging systems, the cytochrome c has several advantages. The heme is covalently bound, renders the proteins visible by optical spectroscopy, and can be used to monitor, quantify, and determine the orientation of the polypeptides in a plethora of experiments. For the antiporter-like subunits NuoL, NuoM, and NuoN and the real antiporters MrpA and MrpD, unprecedented amounts of holo-cytochrome fusion proteins could be obtained in E. coli. The NuoHcyt polypeptide was also efficiently produced, but heme insertion was less effective in this construct. The cytochrome c(550) domain in all the fusion proteins exhibited normal spectra and redox properties, with an E(m) of about +170 mV. The MrpA and MrpD antiporters remained functional after being fused to the cytochrome c-tag. Finally, a his-tag could be added to the cytochrome domain, without any perturbations to the cytochrome properties, allowing efficient purification of the overexpressed fusion proteins.
Collapse
Affiliation(s)
- Tobias Gustavsson
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, 22100 Lund, Sweden
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Spin labeling of the Escherichia coli NADH ubiquinone oxidoreductase (complex I). BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1894-900. [PMID: 20959113 DOI: 10.1016/j.bbabio.2010.10.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2009] [Revised: 09/29/2010] [Accepted: 10/13/2010] [Indexed: 11/20/2022]
Abstract
The proton-pumping NADH:ubiquinone oxidoreductase, the respiratory complex I, couples the transfer of electrons from NADH to ubiquinone with the translocation of protons across the membrane. Electron microscopy revealed the two-part structure of the complex with a peripheral arm involved in electron transfer and a membrane arm most likely involved in proton translocation. It was proposed that the quinone binding site is located at the joint of the two arms. Most likely, proton translocation in the membrane arm is enabled by the energy of the electron transfer reaction in the peripheral arm transmitted by conformational changes. For the detection of the conformational changes and the localization of the quinone binding site, we set up a combination of site-directed spin labeling and EPR spectroscopy. Cysteine residues were introduced to the surface of the Escherichia coli complex I. The spin label (1-oxyl-2,2,5,5-tetramethyl-Δ3-pyrroline-3-methyl)-methanethiosulfonate (MTSL) was exclusively bound to the engineered positions. Neither the mutation nor the labeling had an effect on the NADH:decyl-ubiquinone oxidoreductase activity. The characteristic signals of the spin label were detected by EPR spectroscopy, which did not change by reducing the preparation with NADH. A decyl-ubiquinone derivative with the spin label covalently attached to the alkyl chain was synthesized in order to localize the quinone binding site. The distance between a MTSL labeled complex I variant and the bound quinone was determined by continuous-wave (cw) EPR allowing an inference on the location of the quinone binding site. The distances between the labeled quinone and other complex I variants will be determined in future experiments to receive further geometry information by triangulation.
Collapse
|
31
|
Kakutani N, Murai M, Sakiyama N, Miyoshi H. Exploring the binding site of delta(lac)-acetogenin in bovine heart mitochondrial NADH-ubiquinone oxidoreductase. Biochemistry 2010; 49:4794-803. [PMID: 20459120 DOI: 10.1021/bi100454b] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Biochemical characterization of the inhibition mechanism of Deltalac-acetogenins synthesized in our laboratory indicated that they are a new type of inhibitor of bovine heart mitochondrial NADH-ubiquinone oxidoreductase (complex I) [Murai, M., et al. (2006) Biochemistry 45, 9778-9787]. To identify the binding site of Deltalac-acetogenins with a photoaffinity labeling technique, we synthesized a photoreactive Deltalac-acetogenin ([(125)I]diazinylated Deltalac-acetogenin, [(125)I]DAA) which has a small photoreactive diazirine group attached to a pharmacophore, the bis-THF ring moiety. Characterization of the inhibitory effects of DAA on bovine complex I revealed unique features specific to, though not completely the same as those of, the original Deltalac-acetogenin. Using [(125)I]DAA, we carried out photoaffinity labeling with bovine heart submitochondrial particles. Analysis of the photo-cross-linked protein by Western blotting and immunoprecipitation revealed that [(125)I]DAA binds to the membrane subunit ND1 with high specificity. The photo-cross-linking to the ND1 subunit was suppressed by an exogenous short-chain ubiquinone (Q(2)) in a concentration-dependent manner. Careful examination of the fragmentation patterns of the cross-linked ND1 generated by limited proteolysis using lysylendopeptidase, endoprotease Asp-N, or trypsin and their changes in the presence of the original Deltalac-acetogenin strongly suggested that the cross-linked residues are located at two different sites in the third matrix-side loop connecting the fifth and sixth transmembrane helices.
Collapse
Affiliation(s)
- Nobuyuki Kakutani
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | | | | | | |
Collapse
|
32
|
Efremov RG, Baradaran R, Sazanov LA. The architecture of respiratory complex I. Nature 2010; 465:441-5. [PMID: 20505720 DOI: 10.1038/nature09066] [Citation(s) in RCA: 455] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Accepted: 03/31/2010] [Indexed: 12/12/2022]
Abstract
Complex I is the first enzyme of the respiratory chain and has a central role in cellular energy production, coupling electron transfer between NADH and quinone to proton translocation by an unknown mechanism. Dysfunction of complex I has been implicated in many human neurodegenerative diseases. We have determined the structure of its hydrophilic domain previously. Here, we report the alpha-helical structure of the membrane domain of complex I from Escherichia coli at 3.9 A resolution. The antiporter-like subunits NuoL/M/N each contain 14 conserved transmembrane (TM) helices. Two of them are discontinuous, as in some transporters. Unexpectedly, subunit NuoL also contains a 110-A long amphipathic alpha-helix, spanning almost the entire length of the domain. Furthermore, we have determined the structure of the entire complex I from Thermus thermophilus at 4.5 A resolution. The L-shaped assembly consists of the alpha-helical model for the membrane domain, with 63 TM helices, and the known structure of the hydrophilic domain. The architecture of the complex provides strong clues about the coupling mechanism: the conformational changes at the interface of the two main domains may drive the long amphipathic alpha-helix of NuoL in a piston-like motion, tilting nearby discontinuous TM helices, resulting in proton translocation.
Collapse
Affiliation(s)
- Rouslan G Efremov
- Medical Research Council Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK
| | | | | |
Collapse
|
33
|
Redox-induced conformational changes within the Escherichia coli NADH ubiquinone oxidoreductase (complex I): an analysis by mutagenesis and FT-IR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:659-63. [PMID: 20214873 DOI: 10.1016/j.bbabio.2010.03.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Revised: 02/11/2010] [Accepted: 03/02/2010] [Indexed: 01/24/2023]
Abstract
The proton-pumping NADH:ubiquinone oxidoreductase couples the transfer of electrons from NADH to ubiquinone with the translocation of protons across the membrane. This process is suggested to be accompanied by conformational changes of the enzyme that may be monitored by redox-induced FT-IR difference spectroscopy. Signals observed in the amide I range are partially attributed to local rearrangements that occur as an electrostatic response to the redox reactions of the FeS clusters. In addition, conformational changes can be reported that depend on pH and at the same time can be perturbed by site-directed mutagenesis of residue E67 on subunit B (the bacterial homologue of the mitochondrial PSST subunit). This residue is located in the vicinity of the cluster N2. Re-evaluating these previous data we here discuss a mechanism, by which the redox reaction of N2 induces conformational changes possibly leading to proton translocation.
Collapse
|
34
|
Abstract
Complex I (NADH:quinone oxidoreductase) is crucial to respiration in many aerobic organisms. In mitochondria, it oxidizes NADH (to regenerate NAD+ for the tricarboxylic acid cycle and fatty-acid oxidation), reduces ubiquinone (the electrons are ultimately used to reduce oxygen to water) and transports protons across the mitochondrial inner membrane (to produce and sustain the protonmotive force that supports ATP synthesis and transport processes). Complex I is also a major contributor to reactive oxygen species production in the cell. Understanding the mechanisms of energy transduction and reactive oxygen species production by complex I is not only a significant intellectual challenge, but also a prerequisite for understanding the roles of complex I in disease, and for the development of effective therapies. One approach to defining a complicated reaction mechanism is to break it down into manageable parts that can be tackled individually, before being recombined and integrated to produce the complete picture. Thus energy transduction by complex I comprises NADH oxidation by a flavin mononucleotide, intramolecular electron transfer from the flavin to bound quinone along a chain of iron–sulfur clusters, quinone reduction and proton translocation. More simply, molecular oxygen is reduced by the flavin, to form the reactive oxygen species superoxide and hydrogen peroxide. The present review summarizes and evaluates experimental data that pertain to the reaction mechanisms of complex I, and describes and discusses contemporary mechanistic hypotheses, proposals and models.
Collapse
|
35
|
Berrisford JM, Sazanov LA. Structural basis for the mechanism of respiratory complex I. J Biol Chem 2009; 284:29773-83. [PMID: 19635800 PMCID: PMC2785608 DOI: 10.1074/jbc.m109.032144] [Citation(s) in RCA: 206] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 07/15/2009] [Indexed: 11/06/2022] Open
Abstract
Complex I plays a central role in cellular energy production, coupling electron transfer between NADH and quinone to proton translocation. The mechanism of this highly efficient enzyme is currently unknown. Mitochondrial complex I is a major source of reactive oxygen species, which may be one of the causes of aging. Dysfunction of complex I is implicated in many human neurodegenerative diseases. We have determined several x-ray structures of the oxidized and reduced hydrophilic domain of complex I from Thermus thermophilus at up to 3.1 A resolution. The structures reveal the mode of interaction of complex I with NADH, explaining known kinetic data and providing implications for the mechanism of reactive oxygen species production at the flavin site of complex I. Bound metals were identified in the channel at the interface with the frataxin-like subunit Nqo15, indicating possible iron-binding sites. Conformational changes upon reduction of the complex involve adjustments in the nucleotide-binding pocket, as well as small but significant shifts of several alpha-helices at the interface with the membrane domain. These shifts are likely to be driven by the reduction of nearby iron-sulfur clusters N2 and N6a/b. Cluster N2 is the electron donor to quinone and is coordinated by unique motif involving two consecutive (tandem) cysteines. An unprecedented "on/off switch" (disconnection) of coordinating bonds between the tandem cysteines and this cluster was observed upon reduction. Comparison of the structures suggests a novel mechanism of coupling between electron transfer and proton translocation, combining conformational changes and protonation/deprotonation of tandem cysteines.
Collapse
Affiliation(s)
- John M. Berrisford
- From the Medical Research Council Mitochondrial Biology Unit, Cambridge CB2 0XY, United Kingdom
| | - Leonid A. Sazanov
- From the Medical Research Council Mitochondrial Biology Unit, Cambridge CB2 0XY, United Kingdom
| |
Collapse
|
36
|
Sharma LK, Lu J, Bai Y. Mitochondrial respiratory complex I: structure, function and implication in human diseases. Curr Med Chem 2009; 16:1266-77. [PMID: 19355884 DOI: 10.2174/092986709787846578] [Citation(s) in RCA: 231] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mitochondria are ubiquitous organelles in eukaryotic cells whose primary function is to generate energy supplies in the form of ATP through oxidative phosphorylation. As the entry point for most electrons into the respiratory chain, NADH:ubiquinone oxidoreductase, or complex I, is the largest and least understood component of the mitochondrial oxidative phosphorylation system. Substantial progress has been made in recent years in understanding its subunit composition, its assembly, the interaction among complex I and other respiratory components, and its role in oxidative stress and apoptosis. This review provides an updated overview of the structure of complex I, as well as its cellular functions, and discusses the implication of complex I dysfunction in various human diseases.
Collapse
Affiliation(s)
- Lokendra K Sharma
- Department of Cellular and Structural Biology, University of Texas Health Sciences Center at San Antonio, San Antonio, TX 78229, USA
| | | | | |
Collapse
|
37
|
Couch VA, Medvedev ES, Stuchebrukhov AA. Electrostatics of the FeS clusters in respiratory complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:1266-71. [PMID: 19445896 DOI: 10.1016/j.bbabio.2009.05.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Revised: 04/29/2009] [Accepted: 05/07/2009] [Indexed: 10/20/2022]
Abstract
Respiratory complex I couples the transfer of electrons from NADH to ubiquinone and the translocation of protons across the mitochondrial membrane. A detailed understanding of the midpoint reduction potentials (E(m)) of each redox center and the factors which influence those potentials are critical in the elucidation of the mechanism of electron transfer in this enzyme. We present accurate electrostatic interaction energies for the iron-sulfur (FeS) clusters of complex I to facilitate the development of models and the interpretation of experiments in connection to electron transfer (ET) in this enzyme. To calculate redox titration curves for the FeS clusters it is necessary to include interactions between clusters, which in turn can be used to refine E(m) values and validate spectroscopic assignments of each cluster. Calculated titration curves for clusters N4, N5, and N6a are discussed. Furthermore, we present some initial findings on the electrostatics of the redox centers of complex I under the influence of externally applied membrane potentials. A means of determining the location of the FeS cofactors within the holo-complex based on electrostatic arguments is proposed. A simple electrostatic model of the protein/membrane system is examined to illustrate the viability of our hypothesis.
Collapse
Affiliation(s)
- Vernon A Couch
- Department of Chemistry, University of California, Davis, CA 95616, USA
| | | | | |
Collapse
|
38
|
Zickermann V, Kerscher S, Zwicker K, Tocilescu MA, Radermacher M, Brandt U. Architecture of complex I and its implications for electron transfer and proton pumping. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:574-83. [PMID: 19366614 DOI: 10.1016/j.bbabio.2009.01.012] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Revised: 01/15/2009] [Accepted: 01/15/2009] [Indexed: 11/27/2022]
Abstract
Proton pumping NADH:ubiquinone oxidoreductase (complex I) is the largest and remains by far the least understood enzyme complex of the respiratory chain. It consists of a peripheral arm harbouring all known redox active prosthetic groups and a membrane arm with a yet unknown number of proton translocation sites. The ubiquinone reduction site close to iron-sulfur cluster N2 at the interface of the 49-kDa and PSST subunits has been mapped by extensive site directed mutagenesis. Independent lines of evidence identified electron transfer events during reduction of ubiquinone to be associated with the potential drop that generates the full driving force for proton translocation with a 4H(+)/2e(-) stoichiometry. Electron microscopic analysis of immuno-labelled native enzyme and of a subcomplex lacking the electron input module indicated a distance of 35-60 A of cluster N2 to the membrane surface. Resolution of the membrane arm into subcomplexes showed that even the distal part harbours subunits that are prime candidates to participate in proton translocation because they are homologous to sodium/proton antiporters and contain conserved charged residues in predicted transmembrane helices. The mechanism of redox linked proton translocation by complex I is largely unknown but has to include steps where energy is transmitted over extremely long distances. In this review we compile the available structural information on complex I and discuss implications for complex I function.
Collapse
Affiliation(s)
- Volker Zickermann
- Goethe-Universität, Fachbereich Medizin, Molekulare Bioenergetik, ZBC, Theodor-Stern-Kai 7, Haus 26, D-60590 Frankfurt am Main, Germany
| | | | | | | | | | | |
Collapse
|
39
|
|
40
|
Nucleotide-induced conformational changes in the Escherichia coli NADH:ubiquinone oxidoreductase (complex I). Biochem Soc Trans 2008; 36:971-5. [PMID: 18793172 DOI: 10.1042/bst0360971] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The energy-converting NADH:ubiquinone oxidoreductase, also known as respiratory complex I, couples the transfer of electrons from NADH to ubiquinone with the translocation of protons across the membrane. Electron microscopy revealed the two-part structure of the complex consisting of a peripheral and a membrane arm. The peripheral arm contains all known cofactors and the NADH-binding site, whereas the membrane arm has to be involved in proton translocation. Owing to this, a conformation-linked mechanism for redox-driven proton translocation is discussed. By means of electron microscopy, we show that both arms of the Escherichia coli complex I are widened after the addition of NADH but not of NADPH. NADH-induced conformational changes were also detected in solution: ATR-FTIR (attenuated total reflection Fourier-transform infrared) of the soluble NADH dehydrogenase fragment of the complex indicates protein re-arrangements induced by the addition of NADH. EPR spectroscopy of surface mutants of the complex containing a covalently bound spin label at distinct positions demonstrates NADH-dependent conformational changes in both arms of the complex.
Collapse
|
41
|
Challenges in elucidating structure and mechanism of proton pumping NADH:ubiquinone oxidoreductase (complex I). J Bioenerg Biomembr 2008; 40:475-83. [PMID: 18982432 DOI: 10.1007/s10863-008-9171-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2008] [Accepted: 08/01/2008] [Indexed: 12/11/2022]
Abstract
Proton pumping NADH:ubiquinone oxidoreductase (complex I) is the most complicated and least understood enzyme of the respiratory chain. All redox prosthetic groups reside in the peripheral arm of the L-shaped structure. The NADH oxidation domain harbouring the FMN cofactor is connected via a chain of iron-sulfur clusters to the ubiquinone reduction site that is located in a large pocket formed by the PSST- and 49-kDa subunits of complex I. An access path for ubiquinone and different partially overlapping inhibitor binding regions were defined within this pocket by site directed mutagenesis. A combination of biochemical and single particle analysis studies suggests that the ubiquinone reduction site is located well above the membrane domain. Therefore, direct coupling mechanisms seem unlikely and the redox energy must be converted into a conformational change that drives proton pumping across the membrane arm. It is not known which of the subunits and how many are involved in proton translocation. Complex I is a major source of reactive oxygen species (ROS) that are predominantly formed by electron transfer from FMNH(2). Mitochondrial complex I can cycle between active and deactive forms that can be distinguished by the reactivity towards divalent cations and thiol-reactive agents. The physiological role of this phenomenon is yet unclear but it could contribute to the regulation of complex I activity in-vivo.
Collapse
|
42
|
Ichimaru N, Murai M, Kakutani N, Kako J, Ishihara A, Nakagawa Y, Nishioka T, Yagi T, Miyoshi H. Synthesis and characterization of new piperazine-type inhibitors for mitochondrial NADH-ubiquinone oxidoreductase (complex I). Biochemistry 2008; 47:10816-26. [PMID: 18781777 DOI: 10.1021/bi8010362] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mode of action of Deltalac-acetogenins, strong inhibitors of bovine heart mitochondrial complex I, is different from that of traditional inhibitors such as rotenone and piericidin A [Murai, M., et al. (2007) Biochemistry 46 , 6409-6416]. As further exploration of these unique inhibitors might provide new insights into the terminal electron transfer step of complex I, we drastically modified the structure of Deltalac-acetogenins and characterized their inhibitory action. In particular, on the basis of structural similarity between the bis-THF and the piperazine rings, we here synthesized a series of piperazine derivatives. Some of the derivatives exhibited very potent inhibition at nanomolar levels. The hydrophobicity of the side chains and their balance were important structural factors for the inhibition, as is the case for the original Deltalac-acetogenins. However, unlike in the case of the original Deltalac-acetogenins, (i) the presence of two hydroxy groups is not crucial for the activity, (ii) the level of superoxide production induced by the piperazines is relatively high, (iii) the inhibitory potency for the reverse electron transfer is remarkably weaker than that for the forward event, and (iv) the piperazines efficiently suppressed the specific binding of a photoaffinity probe of natural-type acetogenins ([ (125)I]TDA) to the ND1 subunit. We therefore conclude that the action mechanism of the piperazine series differs from that of the original Deltalac-acetogenins. The photoaffinity labeling study using a newly synthesized photoreactive piperazine ([ (125)I]AFP) revealed that this compound binds to the 49 kDa subunit and an unidentified subunit, not ND1, with a frequency of approximately 1:3. A variety of traditional complex I inhibitors as well as Deltalac-acetogenins suppressed the specific binding of [ (125)I]AFP to the subunits. The apparent competitive behavior of inhibitors that seem to bind to different sites may be due to structural changes at the binding site, rather than occupying the same site. The meaning of the occurrence of diverse inhibitors exhibiting different mechanisms of action is discussed in light of the functionality of the membrane arm of complex I.
Collapse
Affiliation(s)
- Naoya Ichimaru
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Berrisford JM, Thompson CJ, Sazanov LA. Chemical and NADH-induced, ROS-dependent, cross-linking between subunits of complex I from Escherichia coli and Thermus thermophilus. Biochemistry 2008; 47:10262-70. [PMID: 18771280 DOI: 10.1021/bi801160u] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Complex I of respiratory chains transfers electrons from NADH to ubiquinone, coupled to the translocation of protons across the membrane. Two alternative coupling mechanisms are being discussed, redox-driven or conformation-driven. Using "zero-length" cross-linking reagent and isolated hydrophilic domains of complex I from Escherichia coli and Thermus thermophilus, we show that the pattern of cross-links between subunits changes significantly in the presence of NADH. Similar observations were made previously with intact purified E. coli and bovine complex I. This indicates that, upon reduction with NADH, similar conformational changes are likely to occur in the intact enzyme and in the isolated hydrophilic domain (which can be used for crystallographic studies). Within intact E. coli complex I, the cross-link between the hydrophobic subunits NuoA and NuoJ was abolished in the presence of NADH, indicating that conformational changes extend into the membrane domain, possibly as part of a coupling mechanism. Unexpectedly, in the absence of any chemical cross-linker, incubation of complex I with NADH resulted in covalent cross-links between subunits Nqo4 (NuoCD) and Nqo6 (NuoB), as well as between Nqo6 and Nqo9. Their formation depends on the presence of oxygen and so is likely a result of oxidative damage via reactive oxygen species (ROS) induced cross-linking. In addition, ROS- and metal ion-dependent proteolysis of these subunits (as well as Nqo3) is observed. Fe-S cluster N2 is coordinated between subunits Nqo4 and Nqo6 and could be involved in these processes. Our observations suggest that oxidative damage to complex I in vivo may include not only side-chain modifications but also protein cross-linking and degradation.
Collapse
Affiliation(s)
- John M Berrisford
- Medical Research Council Dunn Human Nutrition Unit, Wellcome Trust/MRC building, Hills Road, Cambridge CB2 0XY, UK
| | | | | |
Collapse
|
44
|
Vinogradov AD. NADH/NAD+ interaction with NADH: ubiquinone oxidoreductase (complex I). BIOCHIMICA ET BIOPHYSICA ACTA 2008; 1777:729-34. [PMID: 18471432 PMCID: PMC2494570 DOI: 10.1016/j.bbabio.2008.04.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 03/20/2008] [Accepted: 04/13/2008] [Indexed: 10/22/2022]
Abstract
The quantitative data on the binding affinity of NADH, NAD(+), and their analogues for complex I as emerged from the steady-state kinetics data and from more direct studies under equilibrium conditions are summarized and discussed. The redox-dependency of the nucleotide binding and the reductant-induced change of FMN affinity to its tight non-covalent binding site indicate that binding (dissociation) of the substrate (product) may energetically contribute to the proton-translocating activity of complex I.
Collapse
Affiliation(s)
- Andrei D Vinogradov
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119992, Russian Federation.
| |
Collapse
|
45
|
Papa S, De Rasmo D, Scacco S, Signorile A, Technikova-Dobrova Z, Palmisano G, Sardanelli AM, Papa F, Panelli D, Scaringi R, Santeramo A. Mammalian complex I: a regulable and vulnerable pacemaker in mitochondrial respiratory function. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:719-28. [PMID: 18455500 DOI: 10.1016/j.bbabio.2008.04.005] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Revised: 03/12/2008] [Accepted: 04/05/2008] [Indexed: 10/22/2022]
Abstract
In this paper the regulatory features of complex I of mammalian and human mitochondria are reviewed. In a variety of mitotic cell-line cultures, activation in vivo of the cAMP cascade, or direct addition of cAMP, promotes the NADH-ubiquinone oxidoreductase activity of complex I and lower the cellular level of ROS. These effects of cAMP are found to be associated with PKA-mediated serine phosphorylation in the conserved C-terminus of the subunit of complex I encoded by the nuclear gene NDUFS4. PKA mediated phosphorylation of this Ser in the C-terminus of the protein promotes its mitochondrial import and maturation. Mass-spectrometry analysis of the phosphorylation pattern of complex I subunits is also reviewed.
Collapse
Affiliation(s)
- Sergio Papa
- Department of Medical Biochemistry, Biology and Physics (DIBIFIM), University of Bari, Italy.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Morgan DJ, Sazanov LA. Three-dimensional structure of respiratory complex I from Escherichia coli in ice in the presence of nucleotides. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:711-8. [PMID: 18433710 DOI: 10.1016/j.bbabio.2008.03.023] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Revised: 03/07/2008] [Accepted: 03/25/2008] [Indexed: 11/24/2022]
Abstract
Complex I (NADH:ubiquinone oxidoreductase) is the largest protein complex of bacterial and mitochondrial respiratory chains. The first three-dimensional structure of bacterial complex I in vitrified ice was determined by electron cryo-microscopy and single particle analysis. The structure of the Escherichia coli enzyme incubated with either NAD(+) (as a reference) or NADH was calculated to 35 and 39 A resolution, respectively. The X-ray structure of the peripheral arm of Thermus thermophilus complex I was docked into the reference EM structure. The model obtained indicates that Fe-S cluster N2 is close to the membrane domain interface, allowing for effective electron transfer to membrane-embedded quinone. At the current resolution, the structures in the presence of NAD(+) or NADH are similar. Additionally, side-view class averages were calculated for the negatively stained bovine enzyme. The structures of bovine complex I in the presence of either NAD(+) or NADH also appeared to be similar. These observations indicate that conformational changes upon reduction with NADH, suggested to occur by a range of studies, are smaller than had been thought previously. The model of the entire bacterial complex I could be built from the crystal structures of subcomplexes using the EM envelope described here.
Collapse
Affiliation(s)
- David J Morgan
- Medical Research Council, Dunn Human Nutrition Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 2XY, UK
| | | |
Collapse
|
47
|
Vogel RO, Smeitink JAM, Nijtmans LGJ. Human mitochondrial complex I assembly: A dynamic and versatile process. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:1215-27. [PMID: 17854760 DOI: 10.1016/j.bbabio.2007.07.008] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Revised: 07/24/2007] [Accepted: 07/26/2007] [Indexed: 12/12/2022]
Abstract
One can but admire the intricate way in which biomolecular structures are formed and cooperate to allow proper cellular function. A prominent example of such intricacy is the assembly of the five inner membrane embedded enzymatic complexes of the mitochondrial oxidative phosphorylation (OXPHOS) system, which involves the stepwise combination of >80 subunits and prosthetic groups encoded by both the mitochondrial and nuclear genomes. This review will focus on the assembly of the most complicated OXPHOS structure: complex I (NADH:ubiquinone oxidoreductase, EC 1.6.5.3). Recent studies into complex I assembly in human cells have resulted in several models elucidating a thus far enigmatic process. In this review, special attention will be given to the overlap between the various assembly models proposed in different organisms. Complex I being a complicated structure, its assembly must be prone to some form of coordination. This is where chaperone proteins come into play, some of which may relate complex I assembly to processes such as apoptosis and even immunity.
Collapse
Affiliation(s)
- Rutger O Vogel
- Nijmegen Centre for Mitochondrial Disorders, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Geert Grooteplein 10, 6500 HB Nijmegen, The Netherlands
| | | | | |
Collapse
|
48
|
Grivennikova VG, Kotlyar AB, Karliner JS, Cecchini G, Vinogradov AD. Redox-dependent change of nucleotide affinity to the active site of the mammalian complex I. Biochemistry 2007; 46:10971-8. [PMID: 17760425 PMCID: PMC2258335 DOI: 10.1021/bi7009822] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A very potent and specific inhibitor of mitochondrial NADH:ubiquinone oxidoreductase (complex I), a derivative of NADH (NADH-OH) has recently been discovered (Kotlyar, A. B., Karliner, J. S., and Cecchini, G. (2005) FEBS Lett. 579, 4861-4866). Here we present a quantitative analysis of the interaction of NADH-OH and other nucleotides with oxidized and reduced complex I in tightly coupled submitochondrial particles. Both the rate of the NADH-OH binding and its affinity to complex I are strongly decreased in the presence of succinate. The effect of succinate is completely reversed by rotenone, antimycin A, and uncoupler. The relative affinity of ADP-ribose, a competitive inhibitor of NADH oxidation, is also shown to be significantly affected by enzyme reduction (KD of 30 and 500 microM for oxidized and the succinate-reduced enzyme, respectively). Binding of NADH-OH is shown to abolish the succinate-supported superoxide generation by complex I. Gradual inhibition of the rotenone-sensitive uncoupled NADH oxidase and the reverse electron transfer activities by NADH-OH yield the same final titration point (approximately 0.1 nmol/mg of protein). The titration of NADH oxidase appears as a straight line, whereas the titration of the reverse reaction appears as a convex curve. Possible models to explain the different titration patterns for the forward and reverse reactions are briefly discussed.
Collapse
Affiliation(s)
| | - Alexander B. Kotlyar
- * To whom correspondence should be addressed. (A.D.V.) Phone/fax: 7 495 939 1376. E-mail: . (A.B.K.) Phone: (415) 221-4810 ext. 3416. Fax: (415) 750-6959. E-mail:
| | | | | | - Andrei D. Vinogradov
- * To whom correspondence should be addressed. (A.D.V.) Phone/fax: 7 495 939 1376. E-mail: . (A.B.K.) Phone: (415) 221-4810 ext. 3416. Fax: (415) 750-6959. E-mail:
| |
Collapse
|
49
|
Abstract
The number of NADH dehydrogenases and their role in energy transduction in
Escherchia coli
have been under debate for a long time. Now it is evident that
E. coli
possesses two respiratory NADH dehydrogenases, or NADH:ubiquinone oxidoreductases, that have traditionally been called NDH-I and NDH-II. This review describes the properties of these two NADH dehydrogenases, focusing on the mechanism of the energy converting NADH dehydrogenase as derived from the high resolution structure of the soluble part of the enzyme. In
E. coli
, complex I operates in aerobic and anaerobic respiration, while NDH-II is repressed under anaerobic growth conditions. The insufficient recycling of NADH most likely resulted in excess NADH inhibiting tricarboxylic acid cycle enzymes and the glyoxylate shunt.
Salmonella enterica
serovar Typhimurium complex I mutants are unable to activate ATP-dependent proteolysis under starvation conditions. NDH-II is a single subunit enzyme with a molecular mass of 47 kDa facing the cytosol. Despite the absence of any predicted transmembrane segment it has to be purified in the presence of detergents, and the activity of the preparation is stimulated by an addition of lipids.
Collapse
|
50
|
Kerscher S, Dröse S, Zickermann V, Brandt U. The three families of respiratory NADH dehydrogenases. Results Probl Cell Differ 2007; 45:185-222. [PMID: 17514372 DOI: 10.1007/400_2007_028] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Most reducing equivalents extracted from foodstuffs during oxidative metabolism are fed into the respiratory chains of aerobic bacteria and mitochondria by NADH:quinone oxidoreductases. Three families of enzymes can perform this task and differ remarkably in their complexity and role in energy conversion. Alternative or NDH-2-type NADH dehydrogenases are simple one subunit flavoenzymes that completely dissipate the redox energy of the NADH/quinone couple. Sodium-pumping NADH dehydrogenases (Nqr) that are only found in procaryotes contain several flavins and are integral membrane protein complexes composed of six different subunits. Proton-pumping NADH dehydrogenases (NDH-1 or complex I) are highly complicated membrane protein complexes, composed of up to 45 different subunits, that are found in bacteria and mitochondria. This review gives an overview of the origin, structural and functional properties and physiological significance of these three types of NADH dehydrogenase.
Collapse
Affiliation(s)
- Stefan Kerscher
- Molecular Bioenergetics Group, Centre of Excellence Macromolecular Complexes, Johann Wolfgang Goethe-Universität, 60590, Frankfurt am Main, Germany
| | | | | | | |
Collapse
|