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Lee YT, Savini M, Chen T, Yang J, Zhao Q, Ding L, Gao SM, Senturk M, Sowa JN, Wang JD, Wang MC. Mitochondrial GTP metabolism controls reproductive aging in C. elegans. Dev Cell 2023; 58:2718-2731.e7. [PMID: 37708895 PMCID: PMC10842941 DOI: 10.1016/j.devcel.2023.08.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 07/17/2023] [Accepted: 08/14/2023] [Indexed: 09/16/2023]
Abstract
Healthy mitochondria are critical for reproduction. During aging, both reproductive fitness and mitochondrial homeostasis decline. Mitochondrial metabolism and dynamics are key factors in supporting mitochondrial homeostasis. However, how they are coupled to control reproductive health remains unclear. We report that mitochondrial GTP (mtGTP) metabolism acts through mitochondrial dynamics factors to regulate reproductive aging. We discovered that germline-only inactivation of GTP- but not ATP-specific succinyl-CoA synthetase (SCS) promotes reproductive longevity in Caenorhabditis elegans. We further identified an age-associated increase in mitochondrial clustering surrounding oocyte nuclei, which is attenuated by GTP-specific SCS inactivation. Germline-only induction of mitochondrial fission factors sufficiently promotes mitochondrial dispersion and reproductive longevity. Moreover, we discovered that bacterial inputs affect mtGTP levels and dynamics factors to modulate reproductive aging. These results demonstrate the significance of mtGTP metabolism in regulating oocyte mitochondrial homeostasis and reproductive longevity and identify mitochondrial fission induction as an effective strategy to improve reproductive health.
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Affiliation(s)
- Yi-Tang Lee
- Integrative Program of Molecular and Biochemical Sciences, Baylor College of Medicine, Houston, TX 77030, USA; Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA
| | - Marzia Savini
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA; Graduate Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Tao Chen
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Jin Yang
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Qian Zhao
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Lang Ding
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA; Graduate Program in Chemical, Physical & Structural Biology, Graduate School of Biomedical Science, Baylor College of Medicine, Houston, TX 77030, USA
| | - Shihong Max Gao
- Graduate Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Mumine Senturk
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jessica N Sowa
- Department of Biology, West Chester University, West Chester, PA 19383, USA
| | - Jue D Wang
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Meng C Wang
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.
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2
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Lancaster MS, Graham BH. Succinyl-CoA Synthetase Dysfunction as a Mechanism of Mitochondrial Encephalomyopathy: More than Just an Oxidative Energy Deficit. Int J Mol Sci 2023; 24:10725. [PMID: 37445899 PMCID: PMC10342173 DOI: 10.3390/ijms241310725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/23/2023] [Accepted: 06/25/2023] [Indexed: 07/15/2023] Open
Abstract
Biallelic pathogenic variants in subunits of succinyl-CoA synthetase (SCS), a tricarboxylic acid (TCA) cycle enzyme, are associated with mitochondrial encephalomyopathy in humans. SCS catalyzes the interconversion of succinyl-CoA to succinate, coupled to substrate-level phosphorylation of either ADP or GDP, within the TCA cycle. SCS-deficient encephalomyopathy typically presents in infancy and early childhood, with many patients succumbing to the disease during childhood. Common symptoms include abnormal brain MRI, basal ganglia lesions and cerebral atrophy, severe hypotonia, dystonia, progressive psychomotor regression, and growth deficits. Although subunits of SCS were first identified as causal genes for progressive metabolic encephalomyopathy in the early 2000s, recent investigations are now beginning to unravel the pathomechanisms underlying this metabolic disorder. This article reviews the current understanding of SCS function within and outside the TCA cycle as it relates to the complex and multifactorial mechanisms underlying SCS-related mitochondrial encephalomyopathy.
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Affiliation(s)
| | - Brett H. Graham
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, 975 W. Walnut St., Room IB257, Indianapolis, IN 46202, USA;
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3
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Lee YT, Savini M, Chen T, Yang J, Zhao Q, Ding L, Gao SM, Senturk M, Sowa J, Wang JD, Wang MC. Mitochondrial GTP Metabolism Regulates Reproductive Aging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.02.535296. [PMID: 37066227 PMCID: PMC10103970 DOI: 10.1101/2023.04.02.535296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Healthy mitochondria are critical for reproduction. During aging, both reproductive fitness and mitochondrial homeostasis decline. Mitochondrial metabolism and dynamics are key factors in supporting mitochondrial homeostasis. However, how they are coupled to control reproductive health remains unclear. We report that mitochondrial GTP metabolism acts through mitochondrial dynamics factors to regulate reproductive aging. We discovered that germline-only inactivation of GTP- but not ATP-specific succinyl-CoA synthetase (SCS), promotes reproductive longevity in Caenorhabditis elegans. We further revealed an age-associated increase in mitochondrial clustering surrounding oocyte nuclei, which is attenuated by the GTP-specific SCS inactivation. Germline-only induction of mitochondrial fission factors sufficiently promotes mitochondrial dispersion and reproductive longevity. Moreover, we discovered that bacterial inputs affect mitochondrial GTP and dynamics factors to modulate reproductive aging. These results demonstrate the significance of mitochondrial GTP metabolism in regulating oocyte mitochondrial homeostasis and reproductive longevity and reveal mitochondrial fission induction as an effective strategy to improve reproductive health.
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4
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Ranjan P, Dubey VK. Krebs cycle enzymes for targeted therapeutics and immunotherapy for anti-leishmanial drug development using: Pathways, potential targets, and future perspectives. Life Sci 2022; 322:121314. [PMID: 36566880 DOI: 10.1016/j.lfs.2022.121314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 12/09/2022] [Accepted: 12/17/2022] [Indexed: 12/24/2022]
Abstract
Leishmaniasis is a parasitic and neglected tropical disease which majorly impacts poor and developing nations. One of the significant factors that impacts the severity of the pathological condition includes the socioeconomic background of the affected region. The rise of drug-resistant Leishmania is a serious concern for the effectiveness of the present treatment. As a result, the drug options need to be relooked immediately. Leishmania employs Krebs cycle intermediates for its needs after infection for establishing various defense mechanisms to escape the host immune responses. Nevertheless, a variety of immunological reactions are also seen during infection, which clear the parasites. One of the more promising strategies in this regard would involve combining targeted therapy and immunotherapy. The targeted treatments work by obstructing vital pathways that are required for Leishmania to grow and survive. The mechanism of action of immunotherapy is the control of the host immune response, which entails the blockage of molecular pathways essential for the growth and maintenance of the parasite. The Krebs cycle intermediates have important biochemical roles. Additionally, in macrophages and dendritic cells, they play roles as signalling molecules for controlling inflammatory responses. The review brings together the available literature about the importance of Krebs cycle metabolites as potential treatment targets for leishmaniasis.
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Affiliation(s)
- Preeti Ranjan
- School of Biochemical Engineering, Indian Institute of Technology BHU, Varanasi, UP 221005, India
| | - Vikash Kumar Dubey
- School of Biochemical Engineering, Indian Institute of Technology BHU, Varanasi, UP 221005, India.
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5
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Huang J, Fraser ME. Second distinct conformation of the phosphohistidine loop in succinyl-CoA synthetase. Acta Crystallogr D Struct Biol 2021; 77:357-368. [PMID: 33645539 PMCID: PMC7919408 DOI: 10.1107/s2059798321000334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 01/11/2021] [Indexed: 11/10/2022] Open
Abstract
Succinyl-CoA synthetase (SCS) catalyzes a reversible reaction that is the only substrate-level phosphorylation in the citric acid cycle. One of the essential steps for the transfer of the phosphoryl group involves the movement of the phosphohistidine loop between active site I, where CoA, succinate and phosphate bind, and active site II, where the nucleotide binds. Here, the first crystal structure of SCS revealing the conformation of the phosphohistidine loop in site II of the porcine GTP-specific enzyme is presented. The phosphoryl transfer bridges a distance of 29 Å between the binding sites for phosphohistidine in site I and site II, so these crystal structures support the proposed mechanism of catalysis by SCS. In addition, a second succinate-binding site was discovered at the interface between the α- and β-subunits of SCS, and another magnesium ion was found that interacts with the side chains of Glu141β and Glu204β via water-mediated interactions. These glutamate residues interact with the active-site histidine residue when it is bound in site II.
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Affiliation(s)
- Ji Huang
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Marie E. Fraser
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
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6
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Alkhater RA, Ahonen S, Minassian BA. SUCLA2 Arg407Trp mutation can cause a nonprogressive movement disorder - deafness syndrome. Ann Clin Transl Neurol 2020; 8:252-258. [PMID: 33231368 PMCID: PMC7818133 DOI: 10.1002/acn3.51247] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 10/04/2020] [Accepted: 10/13/2020] [Indexed: 11/25/2022] Open
Abstract
SUCLA2 is a component of mitochondrial succinate‐CoA ligase and nucleotide diphosphokinase activities. Its absence results in Krebs cycle failure, mitochondrial DNA depletion, and a childhood‐fatal encephalomyopathy. We describe a purely neurologic allelic form of the disease consisting of deafness, putamenal hyperintensity on MRI and a myoclonic‐dystonic movement disorder unchanging from childhood into, so far, the late fourth decade. We show that succinate supplementation circumvents the Krebs cycle block, but does not correct the neurologic disease. Our patients’ Arg407Trp mutation has been reported in children with (yet) no MRI abnormalities. It remains possible that early succinate supplementation could impact the disease.
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Affiliation(s)
- Reem A. Alkhater
- Program in Genetics and Genome BiologyThe Hospital for Sick ChildrenTorontoOntarioCanada
- Institute of Medical SciencesUniversity of TorontoTorontoOntarioCanada
- Johns’ Hopkins Aramco HealthcareDhahranSaudi Arabia
| | - Saija Ahonen
- Program in Genetics and Genome BiologyThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Berge A. Minassian
- Program in Genetics and Genome BiologyThe Hospital for Sick ChildrenTorontoOntarioCanada
- Institute of Medical SciencesUniversity of TorontoTorontoOntarioCanada
- Division of NeurologyDepartment of PediatricsUniversity of Texas SouthwesternDallasTexasUSA
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7
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Huang J, Fraser ME. Tartryl-CoA inhibits succinyl-CoA synthetase. Acta Crystallogr F Struct Biol Commun 2020; 76:302-308. [PMID: 32627745 PMCID: PMC7336359 DOI: 10.1107/s2053230x20008201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 06/20/2020] [Indexed: 11/10/2022] Open
Abstract
Succinyl-CoA synthetase (SCS) catalyzes the only substrate-level phosphorylation step in the tricarboxylic acid cycle. Human GTP-specific SCS (GTPSCS), an αβ-heterodimer, was produced in Escherichia coli. The purified protein crystallized from a solution containing tartrate, CoA and magnesium chloride, and a crystal diffracted to 1.52 Å resolution. Tartryl-CoA was discovered to be bound to GTPSCS. The CoA portion lies in the amino-terminal domain of the α-subunit and the tartryl end extends towards the catalytic histidine residue. The terminal carboxylate binds to the phosphate-binding site of GTPSCS.
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Affiliation(s)
- Ji Huang
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Marie E. Fraser
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
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8
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Abstract
A striking change has happened in the field of immunology whereby specific metabolic processes have been shown to be a critical determinant of immune cell activation. Multiple immune receptor types rewire metabolic pathways as a key part of how they promote effector functions. Perhaps surprisingly for immunologists, the Krebs cycle has emerged as the central immunometabolic hub of the macrophage. During proinflammatory macrophage activation, there is an accumulation of the Krebs cycle intermediates succinate and citrate, and the Krebs cycle–derived metabolite itaconate. These metabolites have distinct nonmetabolic signaling roles that influence inflammatory gene expression. A key bioenergetic target for the Krebs cycle, the electron transport chain, also becomes altered, generating reactive oxygen species from Complexes I and III. Similarly, alternatively activated macrophages require α-ketoglutarate-dependent epigenetic reprogramming to elicit anti-inflammatory gene expression. In this review, we discuss these advances and speculate on the possibility of targeting these events therapeutically for inflammatory diseases.
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Affiliation(s)
- Dylan G. Ryan
- School of Biochemistry and Immunology and Trinity Biomedical Sciences Institute, Trinity College, Dublin 2, Ireland
| | - Luke A.J. O'Neill
- School of Biochemistry and Immunology and Trinity Biomedical Sciences Institute, Trinity College, Dublin 2, Ireland
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Huang J, Nguyen VH, Hamblin KA, Maytum R, van der Giezen M, Fraser ME. ATP-specificity of succinyl-CoA synthetase from Blastocystis hominis. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2019; 75:647-659. [PMID: 31282474 DOI: 10.1107/s2059798319007976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 06/03/2019] [Indexed: 11/10/2022]
Abstract
Succinyl-CoA synthetase (SCS) catalyzes the only step of the tricarboxylic acid cycle that leads to substrate-level phosphorylation. Some forms of SCS are specific for ADP/ATP or for GDP/GTP, while others can bind all of these nucleotides, generally with different affinities. The theory of `gatekeeper' residues has been proposed to explain the nucleotide-specificity. Gatekeeper residues lie outside the binding site and create specific electrostatic interactions with incoming nucleotides to determine whether the nucleotides can enter the binding site. To test this theory, the crystal structure of the nucleotide-binding domain in complex with Mg2+-ADP was determined, as well as the structures of four proteins with single mutations, K46βE, K114βD, V113βL and L227βF, and one with two mutations, K46βE/K114βD. The crystal structures show that the enzyme is specific for ADP/ATP because of interactions between the nucleotide and the binding site. Nucleotide-specificity is provided by hydrogen-bonding interactions between the adenine base and Gln20β, Gly111β and Val113β. The O atom of the side chain of Gln20β interacts with N6 of ADP, while the side-chain N atom interacts with the carbonyl O atom of Gly111β. It is the different conformations of the backbone at Gln20β, of the side chain of Gln20β and of the linker that make the enzyme ATP-specific. This linker connects the two subdomains of the ATP-grasp fold and interacts differently with adenine and guanine bases. The mutant proteins have similar conformations, although the L227βF mutant shows structural changes that disrupt the binding site for the magnesium ion. Although the K46βE/K114βD double mutant of Blastocystis hominis SCS binds GTP better than ATP according to kinetic assays, only the complex with Mg2+-ADP was obtained.
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Affiliation(s)
- Ji Huang
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Vinh H Nguyen
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Karleigh A Hamblin
- Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, England
| | - Robin Maytum
- School of Life Sciences, University of Bedfordshire, University Square, Luton LU1 3JU, England
| | | | - Marie E Fraser
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
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10
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Demirbas D, Harris DJ, Arn PH, Huang X, Waisbren SE, Anselm I, Lerner‐Ellis JP, Wong L, Levy HL, Berry GT. Phenotypic variability in deficiency of the α subunit of succinate-CoA ligase. JIMD Rep 2019; 46:63-69. [PMID: 31240156 PMCID: PMC6498818 DOI: 10.1002/jmd2.12018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 12/31/2018] [Indexed: 12/30/2022] Open
Abstract
Succinyl-CoA synthetase or succinate-CoA ligase deficiency can result from biallelic mutations in SUCLG1 gene that encodes for the alpha subunit of the succinyl-CoA synthetase. Mutations in this gene were initially associated with fatal infantile lactic acidosis. We describe an individual with a novel biallelic pathogenic mutation in SUCLG1 with a less severe phenotype dominated by behavioral problems. The mutation was identified to be c.512A>G corresponding to a p.Asn171Ser change in the protein. The liquid chromatography tandem mass spectrometry-based enzyme activity assay on cultured fibroblasts revealed a markedly reduced activity of succinyl-CoA synthetase enzyme when both ATP and GTP were substrates, affecting both ADP-forming and GDP-forming functions of the enzyme.
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Affiliation(s)
- Didem Demirbas
- Division of Genetics and Genomics, Manton Center for Orphan Disease ResearchBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - David J. Harris
- Division of Genetics and Genomics, Manton Center for Orphan Disease ResearchBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - Pamela H. Arn
- Department of PediatricsNemours Children's Health SystemJacksonvilleFlorida
| | - Xiaoping Huang
- Division of Genetics and Genomics, Manton Center for Orphan Disease ResearchBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - Susan E. Waisbren
- Division of Genetics and Genomics, Manton Center for Orphan Disease ResearchBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - Irina Anselm
- Department of NeurologyBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - Jordan P. Lerner‐Ellis
- Division of Genetics and Genomics, Manton Center for Orphan Disease ResearchBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | | | - Harvey L. Levy
- Division of Genetics and Genomics, Manton Center for Orphan Disease ResearchBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
| | - Gerard T. Berry
- Division of Genetics and Genomics, Manton Center for Orphan Disease ResearchBoston Children's Hospital, Harvard Medical SchoolBostonMassachusetts
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Abstract
The heart failure accounts for the highest mortality rate all over the world. The development of preventive therapeutic approaches is still in their infancy. Owing to the extremely high energy demand of the heart, the bioenergetics pathways need to respond efficiently based on substrate availability. The metabolic regulation of such heart bioenergetics is mediated by various rate limiting enzymes involved in energy metabolism. Although all the pertinent mechanisms are not clearly understood, the progressive decline in the activity of metabolic enzymes leading to diminished ATP production is known to cause progression of the heart failure. Therefore, metabolic therapy that can maintain the appropriate activities of metabolic enzymes can be a promising approach for the prevention and treatment of the heart failure. The flavonoids that constitute various human dietary ingredients also effectively offer a variety of health benefits. The flavonoids target a variety of metabolic enzymes and facilitate effective management of the equilibrium between production and utilization of energy in the heart. This review discusses the broad impact of metabolic enzymes in the heart functions and explains how the dysregulated enzyme activity causes the heart failure. In addition, the prospects of targeting dysregulated metabolic enzymes by developing flavonoid-based metabolic approaches are discussed.
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12
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Korge P, Calmettes G, John SA, Weiss JN. Reactive oxygen species production induced by pore opening in cardiac mitochondria: The role of complex III. J Biol Chem 2017; 292:9882-9895. [PMID: 28450391 DOI: 10.1074/jbc.m116.768317] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 04/14/2017] [Indexed: 01/02/2023] Open
Abstract
Recent evidence has implicated succinate-driven reverse electron transport (RET) through complex I as a major source of damaging reactive oxygen species (ROS) underlying reperfusion injury after prolonged cardiac ischemia. However, this explanation may be incomplete, because RET on reperfusion is self-limiting and therefore transient. RET can only generate ROS when mitochondria are well polarized, and it ceases when permeability transition pores (PTP) open during reperfusion. Because prolonged ischemia/reperfusion also damages electron transport complexes, we investigated whether such damage could lead to ROS production after PTP opening has occurred. Using isolated cardiac mitochondria, we demonstrate a novel mechanism by which antimycin-inhibited complex III generates significant amounts of ROS in the presence of Mg2+ and NAD+ and the absence of exogenous substrates upon inner membrane pore formation by alamethicin or Ca2+-induced PTP opening. We show that H2O2 production under these conditions is related to Mg2+-dependent NADH generation by malic enzyme. H2O2 production is blocked by stigmatellin, indicating its origin from complex III, and by piericidin, demonstrating the importance of NADH-related ubiquinone reduction for ROS production under these conditions. For maximal ROS production, the rate of NADH generation has to be equal or below that of NADH oxidation, as further increases in [NADH] elevate ubiquinol-related complex III reduction beyond the optimal range for ROS generation. These results suggest that if complex III is damaged during ischemia, PTP opening may result in succinate/malate-fueled ROS production from complex III due to activation of malic enzyme by increases in matrix [Mg2+], [NAD+], and [ADP].
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Affiliation(s)
- Paavo Korge
- From the UCLA Cardiovascular Research Laboratory and the Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| | - Guillaume Calmettes
- From the UCLA Cardiovascular Research Laboratory and the Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| | - Scott A John
- From the UCLA Cardiovascular Research Laboratory and the Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| | - James N Weiss
- From the UCLA Cardiovascular Research Laboratory and the Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
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13
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Huang J, Fraser ME. Structural basis for the binding of succinate to succinyl-CoA synthetase. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2016; 72:912-21. [PMID: 27487822 DOI: 10.1107/s2059798316010044] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 06/20/2016] [Indexed: 01/19/2023]
Abstract
Succinyl-CoA synthetase catalyzes the only step in the citric acid cycle that provides substrate-level phosphorylation. Although the binding sites for the substrates CoA, phosphate, and the nucleotides ADP and ATP or GDP and GTP have been identified, the binding site for succinate has not. To determine this binding site, pig GTP-specific succinyl-CoA synthetase was crystallized in the presence of succinate, magnesium ions and CoA, and the structure of the complex was determined by X-ray crystallography to 2.2 Å resolution. Succinate binds in the carboxy-terminal domain of the β-subunit. The succinate-binding site is near both the active-site histidine residue that is phosphorylated in the reaction and the free thiol of CoA. The carboxy-terminal domain rearranges when succinate binds, burying this active site. However, succinate is not in position for transfer of the phosphoryl group from phosphohistidine. Here, it is proposed that when the active-site histidine residue has been phosphorylated by GTP, the phosphohistidine displaces phosphate and triggers the movement of the carboxylate of succinate into position to be phosphorylated. The structure shows why succinyl-CoA synthetase is specific for succinate and does not react appreciably with citrate nor with the other C4-dicarboxylic acids of the citric acid cycle, fumarate and oxaloacetate, but shows some activity with L-malate.
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Affiliation(s)
- Ji Huang
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Marie E Fraser
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
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14
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Fratz EJ, Clayton J, Hunter GA, Ducamp S, Breydo L, Uversky VN, Deybach JC, Gouya L, Puy H, Ferreira GC. Human Erythroid 5-Aminolevulinate Synthase Mutations Associated with X-Linked Protoporphyria Disrupt the Conformational Equilibrium and Enhance Product Release. Biochemistry 2015; 54:5617-31. [PMID: 26300302 PMCID: PMC4573335 DOI: 10.1021/acs.biochem.5b00407] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Regulation of 5-aminolevulinate synthase (ALAS) is at the origin of balanced heme production in mammals. Mutations in the C-terminal region of human erythroid-specific ALAS (hALAS2) are associated with X-linked protoporphyria (XLPP), a disease characterized by extreme photosensitivity, with elevated blood concentrations of free protoporphyrin IX and zinc protoporphyrin. To investigate the molecular basis for this disease, recombinant hALAS2 and variants of the enzyme harboring the gain-of-function XLPP mutations were constructed, purified, and analyzed kinetically, spectroscopically, and thermodynamically. Enhanced activities of the XLPP variants resulted from increases in the rate at which the product 5-aminolevulinate (ALA) was released from the enzyme. Circular dichroism spectroscopy revealed that the XLPP mutations altered the microenvironment of the pyridoxal 5'-phosphate cofactor, which underwent further and specific alterations upon succinyl-CoA binding. Transient kinetic analyses of the variant-catalyzed reactions and protein fluorescence quenching upon binding of ALA to the XLPP variants demonstrated that the protein conformational transition step associated with product release was predominantly affected. Of relevance is the fact that XLPP could also be modeled in cell culture. We propose that (1) the XLPP mutations destabilize the succinyl-CoA-induced hALAS2 closed conformation and thus accelerate ALA release, (2) the extended C-terminus of wild-type mammalian ALAS2 provides a regulatory role that allows for allosteric modulation of activity, thereby controlling the rate of erythroid heme biosynthesis, and (3) this control is disrupted in XLPP, resulting in porphyrin accumulation.
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Affiliation(s)
- Erica J. Fratz
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, 33612, USA
| | - Jerome Clayton
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, 33612, USA
| | - Gregory A. Hunter
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, 33612, USA
| | - Sarah Ducamp
- Assistance Publique-Hôpitaux de Paris, Centre Français des Porphyries, Hôpital Louis Mourier, 178 rue des Renouillers, 92701 Colombes CEDEX, France
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l’inflammation, 16 rue Henri Huchard, 75018, Université Paris Diderot, Site Bichat, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France
| | - Leonid Breydo
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, 33612, USA
| | - Vladimir N. Uversky
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, 33612, USA
| | - Jean-Charles Deybach
- Assistance Publique-Hôpitaux de Paris, Centre Français des Porphyries, Hôpital Louis Mourier, 178 rue des Renouillers, 92701 Colombes CEDEX, France
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l’inflammation, 16 rue Henri Huchard, 75018, Université Paris Diderot, Site Bichat, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France
| | - Laurent Gouya
- Assistance Publique-Hôpitaux de Paris, Centre Français des Porphyries, Hôpital Louis Mourier, 178 rue des Renouillers, 92701 Colombes CEDEX, France
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l’inflammation, 16 rue Henri Huchard, 75018, Université Paris Diderot, Site Bichat, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France
| | - Hervé Puy
- Assistance Publique-Hôpitaux de Paris, Centre Français des Porphyries, Hôpital Louis Mourier, 178 rue des Renouillers, 92701 Colombes CEDEX, France
- INSERM U1149, CNRS ERL 8252, Centre de Recherche sur l’inflammation, 16 rue Henri Huchard, 75018, Université Paris Diderot, Site Bichat, 75018 Paris, France; Laboratory of Excellence, GR-Ex, Paris, France
| | - Gloria C. Ferreira
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, 33612, USA
- Department of Chemistry, University of South Florida, Tampa, Florida, 33612, USA
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15
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Huang J, Malhi M, Deneke J, Fraser ME. Structure of GTP-specific succinyl-CoA synthetase in complex with CoA. Acta Crystallogr F Struct Biol Commun 2015; 71:1067-71. [PMID: 26249701 PMCID: PMC4528943 DOI: 10.1107/s2053230x15011188] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 06/09/2015] [Indexed: 11/10/2022] Open
Abstract
Pig GTP-specific succinyl-CoA synthetase is an αβ-heterodimer. The crystal structure of the complex with the substrate CoA was determined at 2.1 Å resolution. The structure shows CoA bound to the amino-terminal domain of the α-subunit, with the free thiol extending from the adenine portion into the site where the catalytic histidine residue resides.
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Affiliation(s)
- Ji Huang
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Manpreet Malhi
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Jan Deneke
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Marie Elizabeth Fraser
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
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16
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Pandey A, Pain J, Ghosh AK, Dancis A, Pain D. Fe-S cluster biogenesis in isolated mammalian mitochondria: coordinated use of persulfide sulfur and iron and requirements for GTP, NADH, and ATP. J Biol Chem 2014; 290:640-57. [PMID: 25398879 DOI: 10.1074/jbc.m114.610402] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Iron-sulfur (Fe-S) clusters are essential cofactors, and mitochondria contain several Fe-S proteins, including the [4Fe-4S] protein aconitase and the [2Fe-2S] protein ferredoxin. Fe-S cluster assembly of these proteins occurs within mitochondria. Although considerable data exist for yeast mitochondria, this biosynthetic process has never been directly demonstrated in mammalian mitochondria. Using [(35)S]cysteine as the source of sulfur, here we show that mitochondria isolated from Cath.A-derived cells, a murine neuronal cell line, can synthesize and insert new Fe-(35)S clusters into aconitase and ferredoxins. The process requires GTP, NADH, ATP, and iron, and hydrolysis of both GTP and ATP is necessary. Importantly, we have identified the (35)S-labeled persulfide on the NFS1 cysteine desulfurase as a genuine intermediate en route to Fe-S cluster synthesis. In physiological settings, the persulfide sulfur is released from NFS1 and transferred to a scaffold protein, where it combines with iron to form an Fe-S cluster intermediate. We found that the release of persulfide sulfur from NFS1 requires iron, showing that the use of iron and sulfur for the synthesis of Fe-S cluster intermediates is a highly coordinated process. The release of persulfide sulfur also requires GTP and NADH, probably mediated by a GTPase and a reductase, respectively. ATP, a cofactor for a multifunctional Hsp70 chaperone, is not required at this step. The experimental system described here may help to define the biochemical basis of diseases that are associated with impaired Fe-S cluster biogenesis in mitochondria, such as Friedreich ataxia.
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Affiliation(s)
- Alok Pandey
- From the Department of Pharmacology and Physiology, New Jersey Medical School, Rutgers University, Newark, New Jersey 07101 and
| | - Jayashree Pain
- From the Department of Pharmacology and Physiology, New Jersey Medical School, Rutgers University, Newark, New Jersey 07101 and
| | - Arnab K Ghosh
- From the Department of Pharmacology and Physiology, New Jersey Medical School, Rutgers University, Newark, New Jersey 07101 and
| | - Andrew Dancis
- the Department of Medicine, Division of Hematology-Oncology, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Debkumar Pain
- From the Department of Pharmacology and Physiology, New Jersey Medical School, Rutgers University, Newark, New Jersey 07101 and
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17
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Localization of SUCLA2 and SUCLG2 subunits of succinyl CoA ligase within the cerebral cortex suggests the absence of matrix substrate-level phosphorylation in glial cells of the human brain. J Bioenerg Biomembr 2014; 47:33-41. [PMID: 25370487 DOI: 10.1007/s10863-014-9586-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 09/21/2014] [Indexed: 10/24/2022]
Abstract
We have recently shown that the ATP-forming SUCLA2 subunit of succinyl-CoA ligase, an enzyme of the citric acid cycle, is exclusively expressed in neurons of the human cerebral cortex; GFAP- and S100-positive astroglial cells did not exhibit immunohistoreactivity or in situ hybridization reactivity for either SUCLA2 or the GTP-forming SUCLG2. However, Western blotting of post mortem samples revealed a minor SUCLG2 immunoreactivity. In the present work we sought to identify the cell type(s) harboring SUCLG2 in paraformaldehyde-fixed, free-floating surgical human cortical tissue samples. Specificity of SUCLG2 antiserum was supported by co-localization with mitotracker orange staining of paraformaldehyde-fixed human fibroblast cultures, delineating the mitochondrial network. In human cortical tissue samples, microglia and oligodendroglia were identified by antibodies directed against Iba1 and myelin basic protein, respectively. Double immunofluorescence for SUCLG2 and Iba1 or myelin basic protein exhibited no co-staining; instead, SUCLG2 appeared to outline the cerebral microvasculature. In accordance to our previous work there was no co-localization of SUCLA2 immunoreactivity with either Iba1 or myelin basic protein. We conclude that SUCLG2 exist only in cells forming the vasculature or its contents in the human brain. The absence of SUCLA2 and SUCLG2 in human glia is in compliance with the presence of alternative pathways occurring in these cells, namely the GABA shunt and ketone body metabolism which do not require succinyl CoA ligase activity, and glutamate dehydrogenase 1, an enzyme exhibiting exquisite sensitivity to inhibition by GTP.
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18
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Characterization of ten heterotetrameric NDP-dependent acyl-CoA synthetases of the hyperthermophilic archaeon Pyrococcus furiosus. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2014; 2014:176863. [PMID: 24669200 PMCID: PMC3942289 DOI: 10.1155/2014/176863] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 12/09/2013] [Indexed: 12/03/2022]
Abstract
The hyperthermophilic archaeon Pyrococcus furiosus grows by fermenting peptides and carbohydrates to organic acids. In the terminal step, acyl-CoA synthetase (ACS) isoenzymes convert acyl-CoA derivatives to the corresponding acid and conserve energy in the form of ATP. ACS1 and ACS2 were previously purified from P. furiosus and have α2β2 structures but the genome contains genes encoding three additional α-subunits. The ten possible combinations of α and β genes were expressed in E. coli and each resulted in stable and active α2β2 isoenzymes. The α-subunit of each isoenzyme determined CoA-based substrate specificity and between them they accounted for the CoA derivatives of fourteen amino acids. The β-subunit determined preference for adenine or guanine nucleotides. The GTP-generating isoenzymes are proposed to play a role in gluconeogenesis by producing GTP for GTP-dependent phosphoenolpyruvate carboxykinase and for other GTP-dependent processes. Transcriptional and proteomic data showed that all ten isoenzymes are constitutively expressed indicating that both ATP and GTP are generated from the metabolism of most of the amino acids. A phylogenetic analysis showed that the ACSs of P. furiosus and other members of the Thermococcales are evolutionarily distinct from those found throughout the rest of biology, including those of other hyperthermophilic archaea.
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19
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Joyce MA, Hayakawa K, Wolodko WT, Fraser ME. Biochemical and structural characterization of the GTP-preferring succinyl-CoA synthetase from Thermus aquaticus. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2012; 68:751-62. [PMID: 22751660 PMCID: PMC3388811 DOI: 10.1107/s0907444912010852] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 03/12/2012] [Indexed: 11/11/2022]
Abstract
Succinyl-CoA synthetase (SCS) from Thermus aquaticus was characterized biochemically via measurements of the activity of the enzyme and determination of its quaternary structure as well as its stability and refolding properties. The enzyme is most active between pH 8.0 and 8.4 and its activity increases with temperature to about 339 K. Gel-filtration chromatography and sedimentation equilibrium under native conditions demonstrated that the enzyme is a heterotetramer of two α-subunits and two β-subunits. The activity assays showed that the enzyme uses either ADP/ATP or GDP/GTP, but prefers GDP/GTP. This contrasts with Escherichia coli SCS, which uses GDP/GTP but prefers ADP/ATP. To understand the nucleotide preference, T. aquaticus SCS was crystallized in the presence of GDP, leading to the determination of the structure in complex with GDP-Mn(2+). A water molecule and Pro20β in T. aquaticus take the place of Gln20β in pig GTP-specific SCS, interacting well with the guanine base and other residues of the nucleotide-binding site. This leads to the preference for GDP/GTP, but does not hinder the binding of ADP/ATP.
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Affiliation(s)
- Michael A. Joyce
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Koto Hayakawa
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - William T. Wolodko
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Marie E. Fraser
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
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20
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Gaster M, Nehlin JO, Minet AD. Impaired TCA cycle flux in mitochondria in skeletal muscle from type 2 diabetic subjects: marker or maker of the diabetic phenotype? Arch Physiol Biochem 2012; 118:156-89. [PMID: 22385297 DOI: 10.3109/13813455.2012.656653] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The diabetic phenotype is complex, requiring elucidation of key initiating defects. Recent research has shown that diabetic myotubes express a primary reduced tricarboxylic acid (TCA) cycle flux. A reduced TCA cycle flux has also been shown both in insulin resistant offspring of T2D patients and exercising T2D patients in vivo. This review will discuss the latest advances in the understanding of the molecular mechanisms regulating the TCA cycle with focus on possible underlying mechanism which could explain the impaired TCA flux in insulin resistant human skeletal muscle in type 2 diabetes. A reduced TCA is both a marker and a maker of the diabetic phenotype.
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Affiliation(s)
- Michael Gaster
- Laboratory of Molecular Physiology, Department of Pathology, Odense University Hospital, Denmark.
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21
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Stobbe MD, Houten SM, Kampen AHC, Wanders RJA, Moerland PD. Improving the description of metabolic networks: the TCA cycle as example. FASEB J 2012; 26:3625-36. [DOI: 10.1096/fj.11-203091] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Miranda D. Stobbe
- Bioinformatics LaboratoryUniversity of AmsterdamAmsterdamThe Netherlands
- Netherlands Bioinformatics CentreNijmegenThe Netherlands
| | - Sander M. Houten
- Laboratory Genetic Metabolic DiseasesAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Antoine H. C. Kampen
- Bioinformatics LaboratoryUniversity of AmsterdamAmsterdamThe Netherlands
- Biosystems Data AnalysisSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamThe Netherlands
- Netherlands Consortium for Systems BiologyUniversity of AmsterdamAmsterdamThe Netherlands
- Netherlands Bioinformatics CentreNijmegenThe Netherlands
| | - Ronald J. A. Wanders
- Laboratory Genetic Metabolic DiseasesAcademic Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands
| | - Perry D. Moerland
- Bioinformatics LaboratoryUniversity of AmsterdamAmsterdamThe Netherlands
- Netherlands Bioinformatics CentreNijmegenThe Netherlands
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22
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Van Hove JLK, Saenz MS, Thomas JA, Gallagher RC, Lovell MA, Fenton LZ, Shanske S, Myers SM, Wanders RJA, Ruiter J, Turkenburg M, Waterham HR. Succinyl-CoA ligase deficiency: a mitochondrial hepatoencephalomyopathy. Pediatr Res 2010; 68:159-64. [PMID: 20453710 PMCID: PMC2928220 DOI: 10.1203/pdr.0b013e3181e5c3a4] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This patient presented on the first day of life with pronounced lactic acidosis with an elevated lactate/pyruvate ratio. Urine organic acids showed Krebs cycle metabolites and mildly elevated methylmalonate and methylcitrate. The acylcarnitine profile showed elevated propionylcarnitine and succinylcarnitine. Amino acids showed elevated glutamic acid, glutamine, proline, and alanine. From the age 2 of mo on, she had elevated transaminases and intermittent episodes of liver failure. Liver biopsy showed steatosis and a decrease of mitochondrial DNA to 50% of control. She had bilateral sensorineural hearing loss. Over the course of the first 2 y of life, she developed a progressively severe myopathy with pronounced muscle weakness eventually leading to respiratory failure, Leigh disease, and recurrent hepatic failure. The hepatic symptoms and the metabolic parameters temporarily improved on treatment with aspartate, but neither muscle symptoms nor brain lesions improved. Laboratory testing revealed a deficiency of succinyl-CoA ligase enzyme activity and protein in fibroblasts because of a novel homozygous mutation in the SUCLG1 gene: c.40A>T (p.M14L). Functional analysis suggests that this methionine is more likely to function as the translation initiator methionine, explaining the pathogenic nature of the mutation. Succinyl-CoA ligase deficiency due to an SUCLG1 mutation is a new cause for mitochondrial hepatoencephalomyopathy.
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Affiliation(s)
- Johan L K Van Hove
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado 80045, USA.
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23
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Valayannopoulos V, Haudry C, Serre V, Barth M, Boddaert N, Arnoux JB, Cormier-Daire V, Rio M, Rabier D, Vassault A, Munnich A, Bonnefont JP, de Lonlay P, Rötig A, Lebre AS. New SUCLG1 patients expanding the phenotypic spectrum of this rare cause of mild methylmalonic aciduria. Mitochondrion 2010; 10:335-41. [PMID: 20197121 DOI: 10.1016/j.mito.2010.02.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 01/20/2010] [Accepted: 02/22/2010] [Indexed: 10/19/2022]
Abstract
Deficiencies in two subunits of the succinyl-coenzyme A synthetase (SCS) have been involved in patients with encephalomyopathy and mild methylmalonic aciduria (MMA). In this study, we described three new SUCLG1 patients and performed a meta-analysis of the literature. Our report enlarges the phenotypic spectrum of SUCLG1 mutations and confirms that a characteristic metabolic profile (presence of MMA and C4-DC carnitine in urines) and basal ganglia MRI lesions are the hallmarks of SCS defects. As mitochondrial DNA depletion in muscle is not a constant finding in SUCLG1 patients, this may suggest that diagnosis should not be based on it, but also that alternative physiopathological mechanisms may be considered to explain the combined respiratory chain deficiency observed in SCS patients.
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Affiliation(s)
- Vassili Valayannopoulos
- Université Paris Descartes, Hôpital Necker-Enfants Malades et Inserm U781 et U797, Départements de Génétique, de Radiologie pédiatrique, des Maladies Métaboliques et de Biochimie B, Paris F-75015, France
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24
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Chinopoulos C, Adam-Vizi V. Mitochondria as ATP consumers in cellular pathology. Biochim Biophys Acta Mol Basis Dis 2009; 1802:221-7. [PMID: 19715757 DOI: 10.1016/j.bbadis.2009.08.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Revised: 07/17/2009] [Accepted: 08/17/2009] [Indexed: 12/21/2022]
Abstract
ATP provided by oxidative phosphorylation supports highly complex and energetically expensive cellular processes. Yet, in several pathological settings, mitochondria could revert to ATP consumption, aggravating an existing cellular pathology. Here we review (i) the pathological conditions leading to ATP hydrolysis by the reverse operation of the mitochondrial F(o)F(1)-ATPase, (ii) molecular and thermodynamic factors influencing the directionality of the F(o)F(1)-ATPase, (iii) the role of the adenine nucleotide translocase as the intermediary adenine nucleotide flux pathway between the cytosol and the mitochondrial matrix when mitochondria become ATP consumers, (iv) the role of the permeability transition pore in bypassing the ANT, thereby allowing the flux of ATP directly to the hydrolyzing F(o)F(1)-ATPase, (v) the impact of the permeability transition pore on glycolytic ATP production, and (vi) endogenous and exogenous interventions for limiting ATP hydrolysis by the mitochondrial F(o)F(1)-ATPase.
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Affiliation(s)
- Christos Chinopoulos
- Department of Medical Biochemistry, Semmelweis University, Neurobiochemical Group, Hungarian Academy of Sciences, Budapest, Hungary
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25
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Shikata K, Fukui T, Atomi H, Imanaka T. A Novel ADP-forming Succinyl-CoA Synthetase in Thermococcus kodakaraensis Structurally Related to the Archaeal Nucleoside Diphosphate-forming Acetyl-CoA Synthetases. J Biol Chem 2007; 282:26963-26970. [PMID: 17640871 DOI: 10.1074/jbc.m702694200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have identified and characterized a structurally novel succinyl-CoA synthetase (SCS) from the hyperthermophilic Archaea Thermococcus kodakaraensis. The presence of an SCS completes the metabolic pathway from glutamate to succinate in Thermococcales, which had not been clarified because of the absence of classical SCS homologs on their genomes. The SCS from T. kodakaraensis (SCS(Tk)) is a heteromeric enzyme (alpha(2)beta(2)) encoded by TK1880 (alpha-subunit) and TK0943 (beta-subunit). Although both SCS(Tk) and classical SCSs harbor the five domains present in enzymes of the acyl-CoA synthetase (nucleoside diphosphate-forming) superfamily, the domain order and distribution among subunits in SCS(Tk) (alpha-subunit, domains 1-2-5; beta-subunit, domains 3-4) are distinct from those of classical SCSs (alpha-subunit, domains 1-2; beta-subunit, domains 3-4-5) and instead resemble the acetyl-CoA synthetases from Pyrococcus furiosus (ACSs I(Pf) and II(Pf)). Comparison of the four Thermococcales genomes revealed that each strain harbors five alpha- and two beta-subunit homologs. Sequence similarity suggests that the beta-subunit of SCS(Tk) is also a component of the presumed ACS II from T. kodakaraensis (ACS II(Tk)). We coexpressed the alpha/beta-genes of SCS(Tk) (TK1880/TK0943) and of ACS II(Tk) (TK0139/TK0943). ACS II(Tk) recognizes a broad range of hydrophobic/aromatic acid compounds, as is the case with ACS II(Pf), whereas SCS(Tk) displays a distinct and relatively strict substrate specificity for several acids, including succinate. This indicates that the alpha-subunits are responsible for the distinct substrate specificities of SCS(Tk) and ACS II(Tk).
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Affiliation(s)
- Kenichi Shikata
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Toshiaki Fukui
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Haruyuki Atomi
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Tadayuki Imanaka
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
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26
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Affiliation(s)
- Patrick F Chinnery
- Mitochondrial Research Group and Institute of Human Genetics, Newcastle University, The Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
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27
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Carrozzo R, Dionisi-Vici C, Steuerwald U, Lucioli S, Deodato F, Di Giandomenico S, Bertini E, Franke B, Kluijtmans LAJ, Meschini MC, Rizzo C, Piemonte F, Rodenburg R, Santer R, Santorelli FM, van Rooij A, Vermunt-de Koning D, Morava E, Wevers RA. SUCLA2 mutations are associated with mild methylmalonic aciduria, Leigh-like encephalomyopathy, dystonia and deafness. Brain 2007; 130:862-74. [PMID: 17301081 DOI: 10.1093/brain/awl389] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
One pedigree with four patients has been recently described with mitochondrial DNA depletion and mutation in SUCLA2 gene leading to succinyl-CoA synthase deficiency. Patients had a Leigh-like encephalomyopathy and deafness but besides the presence of lactic acidosis, the profile of urine organic acid was not reported. We have studied 14 patients with mild 'unlabelled' methylmalonic aciduria (MMA) from 11 families. Eight of the families are from the Faroe Islands, having a common ancestor, and three are from southern Italy. Since the reaction catalysed by succinyl-CoA synthase in the tricarboxylic acid (TCA) cycle represents a distal step of the methylmalonic acid pathway, we investigated the SUCLA2 gene as a candidate gene in our patients. Genetic analysis of the gene in the 14 patients confirmed the defect in all patients and led to the identification of three novel mutations (p.Gly118Arg; p.Arg284Cys; c.534 + 1G --> A). The defect could be convincingly shown at the protein level and our data also confirm the previously described mitochondrial DNA depletion. Defects in SUCLA2 can be found at the metabolite level and are defined by mildly elevated methylmalonic acid and C4-dicarboxylic carnitine concentrations in body fluids in association with variable lactic acidosis. Clinically the diagnosis should be considered in patients with early/neonatal onset encephalomyopathy, dystonia, deafness and Leigh-like MRI abnormalities mainly affecting the putamen and the caudate nuclei. The frequency of the mutated allele in the Faroese population amounted to 2%, corresponding with an estimated homozygote frequency of 1 : 2500. Our data extend knowledge on the genetic defects causing MMA. Our patients present with an early infantile Leigh-like encephalomyopathy with deafness, and later on a progressive dystonia. Mild MMA, lactic acidosis and specific abnormalities in the carnitine ester profile are the biochemical hallmarks of the disease. In view of the frequency of the mutated allele on the Faroe Islands, measures become feasible to prevent the occurrence of the disease on the islands. We confirm and extend the findings on this inborn error of metabolism in the TCA cycle that must be carefully investigated by accurate metabolite analyses.
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Affiliation(s)
- Rosalba Carrozzo
- Unit of Molecular Medicine, Bambino Gesù Children's Hospital, Rome, Italy
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28
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Fraser ME, Hayakawa K, Hume MS, Ryan DG, Brownie ER. Interactions of GTP with the ATP-grasp domain of GTP-specific succinyl-CoA synthetase. J Biol Chem 2006; 281:11058-65. [PMID: 16481318 DOI: 10.1074/jbc.m511785200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Two isoforms of succinyl-CoA synthetase exist in mammals, one specific for ATP and the other for GTP. The GTP-specific form of pig succinyl-CoA synthetase has been crystallized in the presence of GTP and the structure determined to 2.1 A resolution. GTP is bound in the ATP-grasp domain, where interactions of the guanine base with a glutamine residue (Gln-20beta) and with backbone atoms provide the specificity. The gamma-phosphate interacts with the side chain of an arginine residue (Arg-54beta) and with backbone amide nitrogen atoms, leading to tight interactions between the gamma-phosphate and the protein. This contrasts with the structures of ATP bound to other members of the family of ATP-grasp proteins where the gamma-phosphate is exposed, free to react with the other substrate. To test if GDP would interact with GTP-specific succinyl-CoA synthetase in the same way that ADP interacts with other members of the family of ATP-grasp proteins, the structure of GDP bound to GTP-specific succinyl-CoA synthetase was also determined. A comparison of the conformations of GTP and GDP shows that the bases adopt the same position but that changes in conformation of the ribose moieties and the alpha- and beta-phosphates allow the gamma-phosphate to interact with the arginine residue and amide nitrogen atoms in GTP, while the beta-phosphate interacts with these residues in GDP. The complex of GTP with succinyl-CoA synthetase shows that the enzyme is able to protect GTP from hydrolysis when the active-site histidine residue is not in position to be phosphorylated.
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Affiliation(s)
- Marie E Fraser
- Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
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29
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Lambeth DO. Reconsideration of the significance of substrate-level phosphorylation in the citric acid cycle*. BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION : A BIMONTHLY PUBLICATION OF THE INTERNATIONAL UNION OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2006; 34:21-29. [PMID: 21638627 DOI: 10.1002/bmb.2006.49403401021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
For nearly 50 years, students of metabolism in animals have been taught that a substrate-level phosphorylation in the Krebs citric acid cycle produces GTP that subsequently undergoes a transphosphorylation with ADP catalyzed by nucleoside diphosphate kinase. Research in the past decade has revealed that animals also express an ADP-forming succinate-CoA ligase whose activity exceeds that of the GDP-forming enzyme in some tissues. Here I argue that the primary fate of GTP is unlikely to be transphosphorylation with ADP. Rather, two succinate-CoA ligases with different nucleotide specificities have evolved to better integrate and regulate the central metabolic pathways that involve the citric acid cycle. The products of substrate-level phosphorylation, ATP and/or GTP, may represent a pool of nucleotide that has a different phosphorylation potential than the ATP made by oxidative phosphorylation and may be channeled to meet specific needs within mitochondria and the cell. Further research is needed to determine the applicable mechanisms and how they vary in tissues.
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Affiliation(s)
- David O Lambeth
- Department of Biochemistry and Molecular Biology, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58203-9037.
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Elpeleg O, Miller C, Hershkovitz E, Bitner-Glindzicz M, Bondi-Rubinstein G, Rahman S, Pagnamenta A, Eshhar S, Saada A. Deficiency of the ADP-forming succinyl-CoA synthase activity is associated with encephalomyopathy and mitochondrial DNA depletion. Am J Hum Genet 2005; 76:1081-6. [PMID: 15877282 PMCID: PMC1196446 DOI: 10.1086/430843] [Citation(s) in RCA: 248] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2005] [Accepted: 04/07/2005] [Indexed: 11/03/2022] Open
Abstract
The mitochondrial DNA (mtDNA) depletion syndrome is a quantitative defect of mtDNA resulting from dysfunction of one of several nuclear-encoded factors responsible for maintenance of mitochondrial deoxyribonucleoside triphosphate (dNTP) pools or replication of mtDNA. Markedly decreased succinyl-CoA synthetase activity due to a deleterious mutation in SUCLA2, the gene encoding the beta subunit of the ADP-forming succinyl-CoA synthetase ligase, was found in muscle mitochondria of patients with encephalomyopathy and mtDNA depletion. Succinyl-CoA synthetase is invariably in a complex with mitochondrial nucleotide diphosphate kinase; hence, we propose that a defect in the last step of mitochondrial dNTP salvage is a novel cause of the mtDNA depletion syndrome.
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Affiliation(s)
- Orly Elpeleg
- Metabolic Disease Unit, Shaare-Zedek Medical Center, Jerusalem, Israel.
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Lambeth DO, Tews KN, Adkins S, Frohlich D, Milavetz BI. Expression of two succinyl-CoA synthetases with different nucleotide specificities in mammalian tissues. J Biol Chem 2004; 279:36621-4. [PMID: 15234968 DOI: 10.1074/jbc.m406884200] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
For nearly 50 years, succinyl-CoA synthetase in animals was thought to be specific for guanine nucleotides. Recently, we purified and characterized both an ADP-forming succinyl-CoA synthetase from pigeon breast muscle and the GDP-forming enzyme from liver (Johnson, J. D., Muhonen, W. W., and Lambeth, D. O. (1998) J. Biol. Chem. 273, 27573-27579). Using the sequences of the pigeon enzymes as queries in BLAST searches, we obtained genetic evidence that both enzymes are expressed in a wide range of animal species (Johnson, J. D., Mehus, J. G., Tews, K., Milavetz, B. I., and Lambeth, D. O. (1998) J. Biol. Chem. 273, 27580-27586). Here we extend those observations by presenting data from Western and Northern blots and enzymatic assays showing that both proteins are widely expressed in mammals with the relative amounts varying from tissue to tissue. We suggest that both succinyl-CoA synthetases catalyze the reverse reaction in the citric acid cycle in which the ADP-forming enzyme augments ATP production, whereas the GDP-forming enzyme supports GTP-dependent anabolic processes. Widely accepted shuttle mechanisms are invoked to explain how transport of P-enolpyruvate across mitochondrial membranes can transfer high energy phosphate between the cytosol and mitochondrial matrix.
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Affiliation(s)
- David O Lambeth
- Department of Biochemistry and Molecular Biology, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA.
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Kanao T, Fukui T, Atomi H, Imanaka T. Kinetic and biochemical analyses on the reaction mechanism of a bacterial ATP-citrate lyase. EUROPEAN JOURNAL OF BIOCHEMISTRY 2002; 269:3409-16. [PMID: 12135479 DOI: 10.1046/j.1432-1033.2002.03016.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The prokaryotic ATP-citrate lyase is considered to be a key enzyme of the carbon dioxide-fixing reductive tricarboxylic acid (RTCA) cycle. Kinetic examination of the ATP-citrate lyase from the green sulfur bacterium Chlorobium limicola (Cl-ACL), an alpha(4)beta(4) heteromeric enzyme, revealed that the enzyme displayed typical Michaelis-Menten kinetics toward ATP with an apparent K(m) value of 0.21 +/- 0.04 mm. However, strong negative cooperativity was observed with respect to citrate binding, with a Hill coefficient (n(H)) of 0.45. Although the dissociation constant of the first citrate molecule was 0.057 +/- 0.008 mm, binding of the first citrate molecule to the enzyme drastically decreased the affinity of the enzyme for the second molecule by a factor of 23. ADP was a competitive inhibitor of ATP with a K(i) value of 0.037 +/- 0.006 mm. Together with previous findings that the enzyme catalyzed the reaction only in the direction of citrate cleavage, these kinetic features indicated that Cl-ACL can regulate both the direction and carbon flux of the RTCA cycle in C. limicola. Furthermore, in order to gain insight on the reaction mechanism, we performed biochemical analyses of Cl-ACL. His273 of the alpha subunit was indicated to be the phosphorylated residue in the catalytic center, as both catalytic activity and phosphorylation of the enzyme by ATP were abolished in an H273A mutant enzyme. We found that phosphorylation of the subunit was reversible. Nucleotide preference for activity was in good accordance with the preference for phosphorylation of the enzyme. Although residues interacting with nucleotides in the succinyl-CoA synthetase from Escherichia coli were conserved in AclB, AclA alone could be phoshorylated with the same nucleotide specificity observed in the holoenzyme. However, AclB was necessary for enzyme activity and contributed to enhance phosphorylation and stabilization of AclA.
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Affiliation(s)
- Tadayoshi Kanao
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Japan
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33
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Metzler DE, Metzler CM, Sauke DJ. Transferring Groups by Displacement Reactions. Biochemistry 2001. [DOI: 10.1016/b978-012492543-4/50015-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Fraser ME, James MN, Bridger WA, Wolodko WT. Phosphorylated and dephosphorylated structures of pig heart, GTP-specific succinyl-CoA synthetase. J Mol Biol 2000; 299:1325-39. [PMID: 10873456 DOI: 10.1006/jmbi.2000.3807] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Succinyl-CoA synthetase (SCS) catalyzes the reversible phosphorylation/dephosphorylation reaction:¿¿¿rm succinyl ¿hbox ¿-¿CoA+NDP+P_i¿leftrightarrow succinate+CoA+NTP¿¿where N denotes adenosine or guanosine. In the course of the reaction, an essential histidine residue is transiently phosphorylated. We have crystallized and solved the structure of the GTP-specific isoform of SCS from pig heart (EC 6.2.1.4) in both the dephosphorylated and phosphorylated forms. The structures were refined to 2.1 A resolution. In the dephosphorylated structure, the enzyme is stabilized via coordination of a phosphate ion by the active-site histidine residue and the two "power" helices, one contributed by each subunit of the alphabeta-dimer. Small changes in the conformations of residues at the amino terminus of the power helix contributed by the alpha-subunit allow the enzyme to accommodate either the covalently bound phosphoryl group or the free phosphate ion. Structural comparisons are made between the active sites in these two forms of the enzyme, both of which can occur along the catalytic path. Comparisons are also made with the structure of Escherichia coli SCS. The domain that has been shown to bind ADP in E. coli SCS is more open in the pig heart, GTP-specific SCS structure.
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Affiliation(s)
- M E Fraser
- Department of Biochemistry, University of Western Ontario, London, Ontario, Canada N6A 5C1
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Lacombe ML, Milon L, Munier A, Mehus JG, Lambeth DO. The human Nm23/nucleoside diphosphate kinases. J Bioenerg Biomembr 2000; 32:247-58. [PMID: 11768308 DOI: 10.1023/a:1005584929050] [Citation(s) in RCA: 277] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Biochemical experiments over the past 40 years have shown that nucleoside diphosphate (NDP) kinase activity, which catalyzes phosphoryl transfer from a nucleoside triphosphate to a nucleoside diphosphate, is ubiquitously found in organisms from bacteria to human. Over the past 10 years, eight human genes of the nm23/NDP kinase family have been discovered that can be separated into two groups based on analysis of their sequences. In addition to catalysis, which may not be exhibited by all isoforms, evidence for regulatory roles has come recently from the discovery of the genes nm23 and awd, which encode NDP kinases and are involved in tumor metastasis and Drosophila development, respectively. Current work shows that the human NDP kinase genes are differentially expressed in tissues and that their products are targeted to different subcellular locations. This suggests that Nm23/NDP kinases possess different, but specific, functions within the cell, depending on their localization. The roles of NDP kinases in metabolic pathways and nucleic acid synthesis are discussed.
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Affiliation(s)
- M L Lacombe
- INSERM U402, Faculté de Médecine Saint-Antoine, Paris, France.
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Furuyama K, Sassa S. Interaction between succinyl CoA synthetase and the heme-biosynthetic enzyme ALAS-E is disrupted in sideroblastic anemia. J Clin Invest 2000; 105:757-64. [PMID: 10727444 PMCID: PMC377455 DOI: 10.1172/jci6816] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The first and the rate-limiting enzyme of heme biosynthesis is delta-aminolevulinate synthase (ALAS), which is localized in mitochondria. There are 2 tissue-specific isoforms of ALAS, erythroid-specific (ALAS-E) and nonspecific ALAS (ALAS-N). To identify possible mitochondrial factors that modulate ALAS-E function, we screened a human bone marrow cDNA library, using the mitochondrial form of human ALAS-E as a bait protein in the yeast 2-hybrid system. Our screening led to the isolation of the beta subunit of human ATP-specific succinyl CoA synthetase (SCS-betaA). Using transient expression and coimmunoprecipitation, we verified that mitochodrially expressed SCS-betaA associates specifically with ALAS-E and not with ALAS-N. Furthermore, the ALAS-E mutants R411C and M426V associated with SCS-betaA, but the D190V mutant did not. Because the D190V mutant was identified in a patient with pyridoxine-refractory X-linked sideroblastic anemia, our findings suggest that appropriate association of SCS-betaA and ALAS-E promotes efficient use of succinyl CoA by ALAS-E or helps translocate ALAS-E into mitochondria.
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Affiliation(s)
- K Furuyama
- Laboratory of Biochemical Hematology, The Rockefeller University, New York, New York 10021, USA
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Hunger-Glaser I, Linder M, Seebeck T. Histidine-phosphorylation of succinyl CoA synthetase from Trypanosoma brucei. Mol Biochem Parasitol 1999; 100:43-52. [PMID: 10376992 DOI: 10.1016/s0166-6851(99)00025-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The insect form of Trypanosoma brucei depends on respiration for its energy requirements. It contains a fully functional mitochondrion with a complete citric acid cycle. Most of its enyzmes have been characterized to date. The current study presents the characterization of the histidine phosphorylation activity of one of the few remaining enzymes, succinyl CoA synthetase. The trypanosomal enyzme was identified by partial purification, followed by direct protein sequencing. It is rapidly phosphorylated, presumably through auto-phosphorylation, using either ATP or GTP as phosphate donors. The phosphorylation occurs exclusively on histidine residues. The histidine-bound phosphate can be donated to suitable phosphate acceptors in a rapid reaction. This phosphotransfer reaction is highly nucleotide selective, as only ADP, but none of the other nucleoside-diphosphates tested, can be used as a phosphate acceptor.
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Affiliation(s)
- I Hunger-Glaser
- Institut fuer Allgemeine Mikrobiologie, University of Bern, Switzerland
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Johnson JD, Mehus JG, Tews K, Milavetz BI, Lambeth DO. Genetic evidence for the expression of ATP- and GTP-specific succinyl-CoA synthetases in multicellular eucaryotes. J Biol Chem 1998; 273:27580-6. [PMID: 9765291 DOI: 10.1074/jbc.273.42.27580] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Highly ATP- and GTP-specific isoforms of succinyl-CoA synthetase in pigeon incorporate the same alpha-subunit, but different beta-subunits (Johnson, J. D., Muhonen, W. W., and Lambeth, D. O. (1998) J. Biol. Chem. 273, 27573-27579). The sequences of the mature subunits were determined by methods based on reverse transcription-polymerase chain reaction. The 306-residue mature alpha-subunit in pigeon shows >88% identity to its homologues in pig and rat. The sequences of the mature ATP- and GTP-specific beta-subunits (A-beta and G-beta, respectively) in pigeon are 54% identical. These sequences were used to identify expressed sequence tags for human and mouse that were highly homologous to G-beta and A-beta, respectively. The sequences for mature A-beta and G-beta in mouse and human were completed and verified by polymerase chain reaction. The sequence of A-beta in pig was also obtained. The mammalian A-beta sequences show >89% identity to each other; the G-beta sequences are similarly related. However, pairwise comparisons of the A-beta and G-beta sequences revealed <53% identity. Alignment with two sequences of the beta-subunit in Caenorhabditis elegans suggests that the A-beta and G-beta genes arose by duplication early in the evolution of multicellular eucaryotes. The expression of A-beta is strong in numerous mouse and human tissues, which suggests that ATP-specific succinyl-CoA synthetase also plays an important role in species throughout the animal kingdom.
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Affiliation(s)
- J D Johnson
- Department of Biochemistry and Molecular Biology, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota 58202, USA
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