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Bunik VI. Redox-Driven Signaling: 2-Oxo Acid Dehydrogenase Complexes as Sensors and Transmitters of Metabolic Imbalance. Antioxid Redox Signal 2019; 30:1911-1947. [PMID: 30187773 DOI: 10.1089/ars.2017.7311] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
SIGNIFICANCE This article develops a holistic view on production of reactive oxygen species (ROS) by 2-oxo acid dehydrogenase complexes. Recent Advances: Catalytic and structural properties of the complexes and their components evolved to minimize damaging effects of side reactions, including ROS generation, simultaneously exploiting the reactions for homeostatic signaling. CRITICAL ISSUES Side reactions of the complexes, characterized in vitro, are analyzed in view of protein interactions and conditions in vivo. Quantitative data support prevalence of the forward 2-oxo acid oxidation over the backward NADH oxidation in feeding physiologically significant ROS production by the complexes. Special focus on interactions between the active sites within 2-oxo acid dehydrogenase complexes highlights the central relevance of the complex-bound thiyl radicals in regulation of and signaling by complex-generated ROS. The thiyl radicals arise when dihydrolipoyl residues of the complexes regenerate FADH2 from the flavin semiquinone coproduced with superoxide anion radical in 1e- oxidation of FADH2 by molecular oxygen. FUTURE DIRECTIONS Interaction of 2-oxo acid dehydrogenase complexes with thioredoxins (TRXs), peroxiredoxins, and glutaredoxins mediates scavenging of the thiyl radicals and ROS generated by the complexes, underlying signaling of disproportional availability of 2-oxo acids, CoA, and NAD+ in key metabolic branch points through thiol/disulfide exchange and medically important hypoxia-inducible factor, mammalian target of rapamycin (mTOR), poly (ADP-ribose) polymerase, and sirtuins. High reactivity of the coproduced ROS and thiyl radicals to iron/sulfur clusters and nitric oxide, peroxynitrite reductase activity of peroxiredoxins and transnitrosylating function of thioredoxin, implicate the side reactions of 2-oxo acid dehydrogenase complexes in nitric oxide-dependent signaling and damage.
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Affiliation(s)
- Victoria I Bunik
- 1 Belozersky Institute of Physicochemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation.,2 Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russian Federation
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Fitzgerald E, Boardman JP, Drake AJ. Preterm Birth and the Risk of Neurodevelopmental Disorders - Is There a Role for Epigenetic Dysregulation? Curr Genomics 2018; 19:507-521. [PMID: 30386170 PMCID: PMC6158617 DOI: 10.2174/1389202919666171229144807] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 04/06/2017] [Accepted: 12/17/2017] [Indexed: 12/29/2022] Open
Abstract
Preterm Birth (PTB) accounts for approximately 11% of all births worldwide each year and is a profound physiological stressor in early life. The burden of neuropsychiatric and developmental impairment is high, with severity and prevalence correlated with gestational age at delivery. PTB is a major risk factor for the development of cerebral palsy, lower educational attainment and deficits in cognitive functioning, and individuals born preterm have higher rates of schizophrenia, autistic spectrum disorder and attention deficit/hyperactivity disorder. Factors such as gestational age at birth, systemic inflammation, respiratory morbidity, sub-optimal nutrition, and genetic vulnerability are associated with poor outcome after preterm birth, but the mechanisms linking these factors to adverse long term outcome are poorly understood. One potential mechanism linking PTB with neurodevelopmental effects is changes in the epigenome. Epigenetic processes can be defined as those leading to altered gene expression in the absence of a change in the underlying DNA sequence and include DNA methylation/hydroxymethylation and histone modifications. Such epigenetic modifications may be susceptible to environmental stimuli, and changes may persist long after the stimulus has ceased, providing a mechanism to explain the long-term consequences of acute exposures in early life. Many factors such as inflammation, fluctuating oxygenation and excitotoxicity which are known factors in PTB related brain injury, have also been implicated in epigenetic dysfunction. In this review, we will discuss the potential role of epigenetic dysregulation in mediating the effects of PTB on neurodevelopmental outcome, with specific emphasis on DNA methylation and the α-ketoglutarate dependent dioxygenase family of enzymes.
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Affiliation(s)
| | | | - Amanda J. Drake
- Address correspondence to this author at the University/BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen’s Medical Research Institute, Edinburgh EH16 4TJ, UK; Tel: 44 131 2426748; Fax: 44 131 2426779; E-mail:
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Positive correlation between rat brain glutamate concentrations and mitochondrial 2-oxoglutarate dehydrogenase activity. Anal Biochem 2018; 552:100-109. [DOI: 10.1016/j.ab.2018.01.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 12/29/2017] [Accepted: 01/02/2018] [Indexed: 01/08/2023]
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Artiukhov AV, Graf AV, Bunik VI. Directed regulation of multienzyme complexes of 2-oxo acid dehydrogenases using phosphonate and phosphinate analogs of 2-oxo acids. BIOCHEMISTRY (MOSCOW) 2016; 81:1498-1521. [DOI: 10.1134/s0006297916120129] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Grabež V, Kathri M, Phung V, Moe KM, Slinde E, Skaugen M, Saarem K, Egelandsdal B. Protein expression and oxygen consumption rate of early postmortem mitochondria relate to meat tenderness. J Anim Sci 2016; 93:1967-79. [PMID: 26020220 DOI: 10.2527/jas.2014-8575] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Oxygen consumption rate (OCR) of muscle fibers from bovine semimembranosus muscle of 41 animals was investigated 3 to 4 h and 3 wk postmortem. Significant relations (P < 0.05) were found between OCR measurements and Warner-Bratzler shear force measurement. Muscles with high mitochondrial OCR after 3 to 4 h and low nonmitochondrial oxygen consumption gave more tender meat. Tender (22.92 ± 2.2 N/cm2) and tough (72.98 ± 7.2 N/cm2) meat samples (4 samples each), separated based on their OCR measurements, were selected for proteomic studies using mitochondria isolated approximately 2.5 h postmortem. Twenty-six differently expressed proteins (P < 0.05) were identified in tender meat and 19 in tough meat. In tender meat, the more prevalent antioxidant and chaperon enzymes may reduce reactive oxygen species and prolong oxygen removal by the electron transport system (ETS). Glycolytic, Krebs cycle, and ETS enzymes were also more abundant in tender meat
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Wille M, Schümann A, Kreutzer M, Glocker MO, Wree A, Mutzbauer G, Schmitt O. The proteome profiles of the olfactory bulb of juvenile, adult and aged rats - an ontogenetic study. Proteome Sci 2015; 13:8. [PMID: 25709559 PMCID: PMC4337183 DOI: 10.1186/s12953-014-0058-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 12/19/2014] [Indexed: 12/30/2022] Open
Abstract
Background In this study, we searched for proteins that change their expression in the olfactory bulb (oB) of rats during ontogenesis. Up to now, protein expression differences in the developing animal are not fully understood. Our investigation focused on the question whether specific proteins exist which are only expressed during different development stages. This might lead to a better characterization of the microenvironment and to a better determination of factors and candidates that influence the differentiation of neuronal progenitor cells. Results After analyzing the samples by two-dimensional polyacrylamide gel electrophoresis (2DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), it could be shown that the number of expressed proteins differs depending on the developmental stages. Especially members of the functional classes, like proteins of biosynthesis, regulatory proteins and structural proteins, show the highest differential expression in the stages of development analyzed. Conclusion In this study, quantitative changes in the expression of proteins in the oB at different developmental stages (postnatal days (P) 7, 90 and 637) could be observed. Furthermore, the expression of many proteins was found at specific developmental stages. It was possible to identify these proteins which are involved in processes like support of cell migration and differentiation. Electronic supplementary material The online version of this article (doi:10.1186/s12953-014-0058-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Michael Wille
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany
| | - Antje Schümann
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany
| | - Michael Kreutzer
- Proteome Center Rostock, Schillingallee 69, 18055 Rostock, Germany
| | | | - Andreas Wree
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany
| | - Grit Mutzbauer
- Department of Pathology, Josef-Schneider-Str. 2, 97080 Würzburg, Germany
| | - Oliver Schmitt
- Department of Anatomy, Gertrudenstr. 9, 18055 Rostock, Germany
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Bunik VI, Tylicki A, Lukashev NV. Thiamin diphosphate-dependent enzymes: from enzymology to metabolic regulation, drug design and disease models. FEBS J 2013; 280:6412-42. [PMID: 24004353 DOI: 10.1111/febs.12512] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/29/2013] [Accepted: 08/21/2013] [Indexed: 02/06/2023]
Abstract
Bringing a knowledge of enzymology into research in vivo and in situ is of great importance in understanding systems biology and metabolic regulation. The central metabolic significance of thiamin (vitamin B1 ) and its diphosphorylated derivative (thiamin diphosphate; ThDP), and the fundamental differences in the ThDP-dependent enzymes of metabolic networks in mammals versus plants, fungi and bacteria, or in health versus disease, suggest that these enzymes are promising targets for biotechnological and medical applications. Here, the in vivo action of known regulators of ThDP-dependent enzymes, such as synthetic structural analogs of the enzyme substrates and thiamin, is analyzed in light of the enzymological data accumulated during half a century of research. Mimicking the enzyme-specific catalytic intermediates, the phosphonate analogs of 2-oxo acids selectively inhibit particular ThDP-dependent enzymes. Because of their selectivity, use of these compounds in cellular and animal models of ThDP-dependent enzyme malfunctions improves the validity of the model and its predictive power when compared with the nonselective and enzymatically less characterized oxythiamin and pyrithiamin. In vitro studies of the interaction of thiamin analogs and their biological derivatives with potential in vivo targets are necessary to identify and attenuate the analog selectivity. For both the substrate and thiamin synthetic analogs, in vitro reactivities with potential targets are highly relevant in vivo. However, effective concentrations in vivo are often higher than in vitro studies would suggest. The significance of specific inihibition of the ThDP-dependent enzymes for the development of herbicides, antibiotics, anticancer and neuroprotective strategies is discussed.
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Affiliation(s)
- Victoria I Bunik
- A.N. Belozersky Institute of Physicochemical Biology, Lomonosov Moscow State University, Moscow, Russia; Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
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Graf A, Trofimova L, Loshinskaja A, Mkrtchyan G, Strokina A, Lovat M, Tylicky A, Strumilo S, Bettendorff L, Bunik VI. Up-regulation of 2-oxoglutarate dehydrogenase as a stress response. Int J Biochem Cell Biol 2012; 45:175-89. [PMID: 22814169 DOI: 10.1016/j.biocel.2012.07.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2012] [Revised: 06/28/2012] [Accepted: 07/01/2012] [Indexed: 01/08/2023]
Abstract
2-Oxoglutarate dehydrogenase multienzyme complex (OGDHC) operates at a metabolic cross-road, mediating Ca(2+)- and ADP-dependent signals in mitochondria. Here, we test our hypothesis that OGDHC plays a major role in the neurotransmitter metabolism and associated stress response. This possibility was assessed using succinyl phosphonate (SP), a highly specific and efficient in vivo inhibitor of OGDHC. Animals exposed to toxicants (SP, ethanol or MnCl(2)), trauma or acute hypoxia showed intrinsic up-regulation of OGDHC in brain and heart. The known mechanism of the SP action as OGDHC inhibitor pointed to the up-regulation triggered by the enzyme impairment. The animal behavior and skeletal muscle or heart performance were tested to correlate physiology with the OGDHC regulation and associated changes in the glutamate and cellular energy status. The SP-treated animals exhibited interdependent changes in the brain OGDHC activity, glutamate level and cardiac autonomic balance, suggesting the neurotransmitter role of glutamate to be involved in the changed heart performance. Energy insufficiency after OGDHC inhibition was detectable neither in animals up to 25 mg/kg SP, nor in cell culture during 24 h incubation with 0.1 mM SP. However, in animals subjected to acute ethanol intoxication SP did evoke energy deficit, decreasing muscular strength and locomotion and increasing the narcotic sleep duration. This correlated with the SP-induced decrease in NAD(P)H levels of the ethanol-exposed neurons. Thus, we show the existence of natural mechanisms to up-regulate mammalian OGDHC in response to stress, with both the glutamate neurotransmission and energy production potentially involved in the OGDHC impact on physiological performance. This article is part of a Directed Issue entitled: Bioenergetic dysfunction, adaptation and therapy.
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Affiliation(s)
- Anastasia Graf
- Department of Physiology of Biology Faculty of Lomonosov Moscow State University, Leninskije Gory 1, 119992 Moscow, Russian Federation.
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Araújo WL, Tohge T, Nunes-Nesi A, Daloso DM, Nimick M, Krahnert I, Bunik VI, Moorhead GBG, Fernie AR. Phosphonate analogs of 2-oxoglutarate perturb metabolism and gene expression in illuminated Arabidopsis leaves. FRONTIERS IN PLANT SCIENCE 2012; 3:114. [PMID: 22876250 PMCID: PMC3410613 DOI: 10.3389/fpls.2012.00114] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2012] [Accepted: 05/14/2012] [Indexed: 05/19/2023]
Abstract
Although the role of the 2-oxoglutarate dehydrogenase complex (2-OGDHC) has previously been demonstrated in plant heterotrophic tissues its role in photosynthetically active tissues remains poorly understood. By using a combination of metabolite and transcript profiles we here investigated the function of 2-OGDHC in leaves of Arabidopsis thaliana via use of specific phosphonate inhibitors of the enzyme. Incubation of leaf disks with the inhibitors revealed that they produced the anticipated effects on the in situ enzyme activity. In vitro experiments revealed that succinyl phosphonate (SP) and a carboxy ethyl ester of SP are slow-binding inhibitors of the 2-OGDHC. Our results indicate that the reduced respiration rates are associated with changes in the regulation of metabolic and signaling pathways leading to an imbalance in carbon-nitrogen metabolism and cell homeostasis. The inducible alteration of primary metabolism was associated with altered expression of genes belonging to networks of amino acids, plant respiration, and sugar metabolism. In addition, by using isothermal titration calorimetry we excluded the possibility that the changes in gene expression resulted from an effect on 2-oxoglutarate (2OG) binding to the carbon/ATP sensing protein PII. We also demonstrated that the 2OG degradation by the 2-oxoglutarate dehydrogenase strongly influences the distribution of intermediates of the tricarboxylic acid (TCA) cycle and the GABA shunt. Our results indicate that the TCA cycle activity is clearly working in a non-cyclic manner upon 2-OGDHC inhibition during the light period.
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Affiliation(s)
- Wagner L. Araújo
- Max-Planck-Institut für Molekulare PflanzenphysiologiePotsdam-Golm, Germany
- Departamento de Biologia Vegetal, Universidade Federal de ViçosaViçosa, Minas Gerais, Brazil
| | - Takayuki Tohge
- Max-Planck-Institut für Molekulare PflanzenphysiologiePotsdam-Golm, Germany
| | - Adriano Nunes-Nesi
- Max-Planck Partner Group, Departamento de Biologia Vegetal, Universidade Federal de ViçosaViçosa, Minas Gerais, Brazil
| | - Danilo M. Daloso
- Max-Planck-Institut für Molekulare PflanzenphysiologiePotsdam-Golm, Germany
- Departamento de Biologia Vegetal, Universidade Federal de ViçosaViçosa, Minas Gerais, Brazil
| | - Mhairi Nimick
- Department of Biological Sciences, University of CalgaryCalgary, AB, Canada
| | - Ina Krahnert
- Max-Planck-Institut für Molekulare PflanzenphysiologiePotsdam-Golm, Germany
| | - Victoria I. Bunik
- A.N. Belozersly Institute of Physico-Chemical Biology, Moscow State UniversityMoscow, Russia
| | | | - Alisdair R. Fernie
- Max-Planck-Institut für Molekulare PflanzenphysiologiePotsdam-Golm, Germany
- *Correspondence: Alisdair R. Fernie, Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany. e-mail:
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Li Q, Laumonnier Y, Syrovets T, Simmet T. Yeast two-hybrid screening of proteins interacting with plasmin receptor subunit: C-terminal fragment of annexin A2. Acta Pharmacol Sin 2011; 32:1411-8. [PMID: 21963895 DOI: 10.1038/aps.2011.121] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
AIM To identify proteins that interact with the C-terminal fragment of annexin A2 (A2IC), generated by plasmin cleavage of the plasmin receptor, a heterotetramer (AA2t) containing annexin A2. METHODS The gene that encodes the A2IC fragment was obtained from PCR-amplified cDNA isolated from human monocytes, and was ligated into the pBTM116 vector using a DNA ligation kit. The resultant plasmid (pBTM116-A2IC) was sequenced with an ABI PRISM 310 Genetic Analyzer. The expression of an A2IC bait protein fused with a LexA-DNA binding domain (BD) was determined using Western blot analysis. The identification of proteins that interact with A2IC and are encoded in a human monocyte cDNA library was performed using yeast two-hybrid screening. The DNA sequences of the relevant cDNAs were determined using an ABI PRISM BigDye terminator cycle sequencing ready reaction kit. Nucleotide sequence databases were searched for homologous sequences using BLAST search analysis (http://www.ncbi.nlm.nih.gov). Confirmation of the interaction between the protein LexA-A2IC and each of cathepsin S and SNX17 was conducted using a small-scale yeast transformation and X-gal assay. RESULTS The yeast transformed with plasmids encoding the bait proteins were screened with a human monocyte cDNA library by reconstituting full-length transcription factors containing the GAL4-active domain (GAL4-AD) as the prey in a yeast two-hybrid approach. After screening 1×10(7) clones, 23 independent β-Gal-positive clones were identified. Sequence analysis and a database search revealed that 15 of these positive clones matched eight different proteins (SNX17, ProCathepsin S, RPS2, ZBTB4, OGDH, CCDC32, PAPD4, and actin which was already known to interact with annexin A2). CONCLUSION A2IC A2IC interacts with various proteins to form protein complexes, which may contribute to the molecular mechanism of monocyte activation induced by plasmin. The yeast two-hybrid system is an efficient approach for investigating protein interactions.
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Trofimova L, Lovat M, Groznaya A, Efimova E, Dunaeva T, Maslova M, Graf A, Bunik V. Behavioral impact of the regulation of the brain 2-oxoglutarate dehydrogenase complex by synthetic phosphonate analog of 2-oxoglutarate: implications into the role of the complex in neurodegenerative diseases. Int J Alzheimers Dis 2010; 2010:749061. [PMID: 21049004 PMCID: PMC2964918 DOI: 10.4061/2010/749061] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2010] [Revised: 07/05/2010] [Accepted: 09/30/2010] [Indexed: 11/20/2022] Open
Abstract
Decreased activity of the mitochondrial 2-oxoglutarate dehydrogenase complex (OGDHC) in brain accompanies neurodegenerative diseases. To reveal molecular mechanisms of this association, we treated rats with a specific inhibitor of OGDHC, succinyl phosphonate, or exposed them to hypoxic stress. In males treated with succinyl phosphonate and in pregnancy-sensitized females experiencing acute hypobaric hypoxia, we revealed upregulation of brain OGDHC (within 24 hours), with the activity increase presumably representing the compensatory response of brain to the OGDHC inhibition. This up-regulation of brain OGDHC was accompanied by an increase in exploratory activity and a decrease in anxiety of the experimental animals. Remarkably, the hypoxia-induced elevation of brain OGDHC and most of the associated behavioral changes were abrogated by succinyl phosphonate. The antagonistic action of hypoxia and succinyl phosphonate demonstrates potential therapeutic significance of the OGDHC regulation by the phosphonate analogs of 2-oxoglutarate.
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Affiliation(s)
- L Trofimova
- Departments of Biophysics, Biology Faculty, Lomonosov Moscow State University, Moscow 119992, Russia
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Metabolic control exerted by the 2-oxoglutarate dehydrogenase reaction: a cross-kingdom comparison of the crossroad between energy production and nitrogen assimilation. Biochem J 2009; 422:405-21. [PMID: 19698086 DOI: 10.1042/bj20090722] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mechanism-based inhibitors and both forward and reverse genetics have proved to be essential tools in revealing roles for specific enzymatic processes in cellular function. Here, we review experimental studies aimed at assessing the impact of OG (2-oxoglutarate) oxidative decarboxylation on basic cellular activities in a number of biological systems. After summarizing the catalytic and regulatory properties of the OGDHC (OG dehydrogenase complex), we describe the evidence that has been accrued on its cellular role. We demonstrate an essential role of this enzyme in metabolic control in a wide range of organisms. Targeting this enzyme in different cells and tissues, mainly by its specific inhibitors, effects changes in a number of basic functions, such as mitochondrial potential, tissue respiration, ROS (reactive oxygen species) production, nitrogen metabolism, glutamate signalling and survival, supporting the notion that the evolutionary conserved reaction of OG degradation is required for metabolic adaptation. In particular, regulation of OGDHC under stress conditions may be essential to overcome glutamate excitotoxicity in neurons or affect the wound response in plants. Thus, apart from its role in producing energy, the flux through OGDHC significantly affects nitrogen assimilation and amino acid metabolism, whereas the side reactions of OGDHC, such as ROS production and the carboligase reaction, have biological functions in signalling and glyoxylate utilization. Our current view on the role of OGDHC reaction in various processes within complex biological systems allows us a far greater fundamental understanding of metabolic regulation and also opens up new opportunities for us to address both biotechnological and medical challenges.
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