1
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Azarkina NV, Borisov VB, Oleynikov IP, Sudakov RV, Vygodina TV. Interaction of Terminal Oxidases with Amphipathic Molecules. Int J Mol Sci 2023; 24:ijms24076428. [PMID: 37047401 PMCID: PMC10095113 DOI: 10.3390/ijms24076428] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 03/26/2023] [Accepted: 03/27/2023] [Indexed: 04/14/2023] Open
Abstract
The review focuses on recent advances regarding the effects of natural and artificial amphipathic compounds on terminal oxidases. Terminal oxidases are fascinating biomolecular devices which couple the oxidation of respiratory substrates with generation of a proton motive force used by the cell for ATP production and other needs. The role of endogenous lipids in the enzyme structure and function is highlighted. The main regularities of the interaction between the most popular detergents and terminal oxidases of various types are described. A hypothesis about the physiological regulation of mitochondrial-type enzymes by lipid-soluble ligands is considered.
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Affiliation(s)
- Natalia V Azarkina
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 40, 119992 Moscow, Russia
| | - Vitaliy B Borisov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 40, 119992 Moscow, Russia
| | - Ilya P Oleynikov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 40, 119992 Moscow, Russia
| | - Roman V Sudakov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 40, 119992 Moscow, Russia
| | - Tatiana V Vygodina
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory 1, Bld. 40, 119992 Moscow, Russia
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2
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Rottenberg H. The accelerated evolution of human cytochrome c oxidase - Selection for reduced rate and proton pumping efficiency? BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2022; 1863:148595. [PMID: 35850262 DOI: 10.1016/j.bbabio.2022.148595] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 07/02/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
The cytochrome c oxidase complex, complex VI (CIV), catalyzes the terminal step of the mitochondrial electron transport chain where the reduction of oxygen to water by cytochrome c is coupled to the generation of a protonmotive force that drive the synthesis of ATP. CIV evolution was greatly accelerated in humans and other anthropoid primates and appears to be driven by adaptive selection. However, it is not known if there are significant functional differences between the anthropoid primates CIV, and other mammals. Comparison of the high-resolution structures of bovine CIV, mouse CIV and human CIV shows structural differences that are associated with anthropoid-specific substitutions. Here I examine the possible effects of these substitutions in four CIV peptides that are known to affect proton pumping: the mtDNA-coded subunits I, II and III, and the nuclear-encoded subunit VIa2. I conclude that many of the anthropoid-specific substitutions could be expected to modulate the rate and/or the efficiency of proton pumping. These results are compatible with the previously proposed hypothesis that the accelerated evolution of CIV in anthropoid primates is driven by selection pressure to lower the mitochondrial protonmotive force and thus decrease the rate of superoxide generation by mitochondria.
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Affiliation(s)
- Hagai Rottenberg
- New Hope Biomedical R&D, 23 W. Bridge Street, New Hope, PA 18938, USA.
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3
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Jiang Z, Shen T, Huynh H, Fang X, Han Z, Ouyang K. Cardiolipin Regulates Mitochondrial Ultrastructure and Function in Mammalian Cells. Genes (Basel) 2022; 13:genes13101889. [PMID: 36292774 PMCID: PMC9601307 DOI: 10.3390/genes13101889] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/13/2022] [Accepted: 10/14/2022] [Indexed: 12/01/2022] Open
Abstract
Cardiolipin (CL) is a unique, tetra-acylated diphosphatidylglycerol lipid that mainly localizes in the inner mitochondria membrane (IMM) in mammalian cells and plays a central role in regulating mitochondrial architecture and functioning. A deficiency of CL biosynthesis and remodeling perturbs mitochondrial functioning and ultrastructure. Clinical and experimental studies on human patients and animal models have also provided compelling evidence that an abnormal CL content, acyl chain composition, localization, and level of oxidation may be directly linked to multiple diseases, including cardiomyopathy, neuronal dysfunction, immune cell defects, and metabolic disorders. The central role of CL in regulating the pathogenesis and progression of these diseases has attracted increasing attention in recent years. In this review, we focus on the advances in our understanding of the physiological roles of CL biosynthesis and remodeling from human patients and mouse models, and we provide an overview of the potential mechanism by which CL regulates the mitochondrial architecture and functioning.
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Affiliation(s)
- Zhitong Jiang
- Department of Cardiovascular Surgery, Peking University Shenzhen Hospital, Shenzhen 518055, China
| | - Tao Shen
- Department of Cardiovascular Surgery, Peking University Shenzhen Hospital, Shenzhen 518055, China
| | - Helen Huynh
- Department of Medicine, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA 92093, USA
| | - Xi Fang
- Department of Medicine, University of California San Diego, 9500 Gilman Drive, La Jolla, San Diego, CA 92093, USA
| | - Zhen Han
- Department of Cardiovascular Surgery, Peking University Shenzhen Hospital, Shenzhen 518055, China
- Correspondence: (Z.H.); (K.O.)
| | - Kunfu Ouyang
- Department of Cardiovascular Surgery, Peking University Shenzhen Hospital, Shenzhen 518055, China
- Correspondence: (Z.H.); (K.O.)
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4
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Winter JM, Yadav T, Rutter J. Stressed to death: Mitochondrial stress responses connect respiration and apoptosis in cancer. Mol Cell 2022; 82:3321-3332. [PMID: 35961309 PMCID: PMC9481690 DOI: 10.1016/j.molcel.2022.07.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 06/27/2022] [Accepted: 07/18/2022] [Indexed: 11/30/2022]
Abstract
Mitochondrial energetics and respiration have emerged as important factors in how cancer cells respond to or evade apoptotic signals. The study of the functional connection between these two processes may provide insight into following questions old and new: how might we target respiration or downstream signaling pathways to amplify apoptotic stress in the context of cancer therapy? Why are respiration and apoptotic regulation housed in the same organelle? Here, we briefly review mitochondrial respiration and apoptosis and then focus on how the intersection of these two processes is regulated by cytoplasmic signaling pathways such as the integrated stress response.
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Affiliation(s)
- Jacob M Winter
- Department of Biochemistry, Spencer Fox Eccles School of Medicine, The University of Utah, Salt Lake City, UT, USA
| | - Tarun Yadav
- Department of Biochemistry, Spencer Fox Eccles School of Medicine, The University of Utah, Salt Lake City, UT, USA; Department of Biology, Indian Institute of Science Education and Research, Pune, Maharashtra, India
| | - Jared Rutter
- Department of Biochemistry, Spencer Fox Eccles School of Medicine, The University of Utah, Salt Lake City, UT, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA; Huntsman Cancer Institute, The University of Utah, Salt Lake City, UT, USA.
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5
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Hernansanz-Agustín P, Enríquez JA. Functional segmentation of CoQ and cyt c pools by respiratory complex superassembly. Free Radic Biol Med 2021; 167:232-242. [PMID: 33722627 DOI: 10.1016/j.freeradbiomed.2021.03.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/23/2021] [Accepted: 03/07/2021] [Indexed: 12/25/2022]
Abstract
Electron transfer between respiratory complexes is an essential step for the efficiency of the mitochondrial oxidative phosphorylation. Until recently, it was stablished that ubiquinone and cytochrome c formed homogenous single pools in the inner mitochondrial membrane which were not influenced by the presence of respiratory supercomplexes. However, this idea was challenged by the fact that bottlenecks in electron transfer appeared after disruption of supercomplexes into their individual complexes. The postulation of the plasticity model embraced all these observations and concluded that complexes and supercomplexes co-exist and are dedicated to a spectrum of metabolic requirements. Here, we review the involvement of superassembly in complex I stability, the role of supercomplexes in ROS production and the segmentation of the CoQ and cyt c pools, together with their involvement in signaling and disease. Taking apparently conflicting literature we have built up a comprehensive model for the segmentation of CoQ and cyt c mediated by supercomplexes, discuss the current limitations and provide a prospect of the current knowledge in the field.
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Affiliation(s)
- Pablo Hernansanz-Agustín
- Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III CNIC, Melchor Fernández Almagro 3, Madrid, 28029, Spain.
| | - José Antonio Enríquez
- Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III CNIC, Melchor Fernández Almagro 3, Madrid, 28029, Spain; Centro de Investigaciones Biomédicas en Red de Fragilidad y Envejecimiento Saludable-CIBERFES. Av. Monforte de Lemos, 3-5. Pabellón 11, Planta 0 28029, Madrid, Spain.
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6
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The Interplay among Subunit Composition, Cardiolipin Content, and Aggregation State of Bovine Heart Cytochrome c Oxidase. Cells 2020; 9:cells9122588. [PMID: 33287231 PMCID: PMC7761698 DOI: 10.3390/cells9122588] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/24/2020] [Accepted: 12/01/2020] [Indexed: 02/07/2023] Open
Abstract
Mitochondrial cytochrome c oxidase (CcO) is a multisubunit integral membrane complex consisting of 13 dissimilar subunits, as well as three to four tightly bound molecules of cardiolipin (CL). The monomeric unit of CcO is able to form a dimer and participate in the formation of supercomplexes in the inner mitochondrial membrane. The structural and functional integrity of the enzyme is crucially dependent on the full subunit complement and the presence of unperturbed bound CL. A direct consequence of subunit loss, CL removal, or its oxidative modification is the destabilization of the quaternary structure, loss of the activity, and the inability to dimerize. Thus, the intimate interplay between individual components of the complex is imperative for regulation of the CcO aggregation state. While it appears that the aggregation state of CcO might affect its conformational stability, the functional role of the aggregation remains unclear as both monomeric and dimeric forms of CcO seem to be fully active. Here, we review the current status of our knowledge with regard to the role of dimerization in the function and stability of CcO and factors, such as subunit composition, amphiphilic environment represented by phospholipids/detergents, and posttranslational modifications that play a role in the regulation of the CcO aggregation state.
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7
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Zichri SB, Kolusheva S, Shames AI, Schneiderman EA, Poggio JL, Stein DE, Doubijensky E, Levy D, Orynbayeva Z, Jelinek R. Mitochondria membrane transformations in colon and prostate cancer and their biological implications. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183471. [PMID: 32931774 DOI: 10.1016/j.bbamem.2020.183471] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 08/31/2020] [Accepted: 09/02/2020] [Indexed: 01/05/2023]
Abstract
Mitochondria have emerged as important determinants in cancer progression and malignancy. However, the role of mitochondrial membranes in cancer onset and progression has not been thoroughly investigated. This study compares the structural and functional properties of mitochondrial membranes in prostate and colon cancer cells in comparison to normal mitochondria, and possible therapeutic implications of these membrane changes. Specifically, isolation of cell mitochondria and preparation of inverted sub-mitochondrial particles (SMPs) illuminated significant cancer-induced modulations of membrane lipid compositions, fluidity, and activity of cytochrome c oxidase, one of the key mitochondrial enzymes. The experimental data further show that cancer-associated membrane transformations may account for mitochondria targeting by betulinic acid and resveratrol, known anti-cancer molecules. Overall, this study probes the relationship between cancer and mitochondrial membrane transformations, underlying a potential therapeutic significance for mitochondrial membrane targeting in cancer.
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Affiliation(s)
- Shani Ben Zichri
- Department of Chemistry, Ben-Gurion University, Beer-Sheva 84105, Israel
| | - Sofiya Kolusheva
- Ilze Katz Center for Nanotechnology, Ben-Gurion University, Beer-Sheva 84105, Israel
| | | | - Elina Abaev Schneiderman
- Department of Microbiology, Immunology and Genetics, Faculty for Health Sciences, Ben-Gurion University, Beer-Sheva 84105, Israel
| | - Juan L Poggio
- Department of Surgery, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - David E Stein
- Department of Surgery, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Elena Doubijensky
- Ilze Katz Center for Nanotechnology, Ben-Gurion University, Beer-Sheva 84105, Israel
| | - Dan Levy
- Department of Microbiology, Immunology and Genetics, Faculty for Health Sciences, Ben-Gurion University, Beer-Sheva 84105, Israel
| | - Zulfiya Orynbayeva
- Department of Surgery, Drexel University College of Medicine, Philadelphia, PA 19102, USA.
| | - Raz Jelinek
- Department of Chemistry, Ben-Gurion University, Beer-Sheva 84105, Israel; Ilze Katz Center for Nanotechnology, Ben-Gurion University, Beer-Sheva 84105, Israel.
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8
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Acaz-Fonseca E, Ortiz-Rodriguez A, Garcia-Segura LM, Astiz M. Sex differences and gonadal hormone regulation of brain cardiolipin, a key mitochondrial phospholipid. J Neuroendocrinol 2020; 32:e12774. [PMID: 31323169 DOI: 10.1111/jne.12774] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 06/14/2019] [Accepted: 07/15/2019] [Indexed: 12/14/2022]
Abstract
Cardiolipin (CL) is a phospholipid that is almost exclusively located in the inner mitochondrial membrane of eukaryotic cells. As a result of its unique structure and distribution, CL establishes non-covalent bonds with a long list of proteins involved in ATP production, mitochondria biogenesis, mitophagy and apoptosis. Thus, the amount of CL, as well as its fatty acid composition and location, strongly impacts upon mitochondrial-dependent functions and therefore the metabolic homeostasis of different tissues. The brain is particularly sensitive to mitochondrial dysfunction as a result of its high metabolic demand. Several mitochondrial related-neurodegenerative disorders, as well as physiological ageing, show altered CL metabolism. Furthermore, mice lacking enzymes involved in CL synthesis show cognitive impairments. CL content and metabolism are regulated by gonadal hormones in the developing and adult brain. In neuronal cultures, oestradiol increases CL content, whereas adult ovariectomy decreases CL content and alters CL metabolism in the hippocampal mitochondria. Transient sex differences in brain CL metabolism have been detected during development. At birth, brain CL has a higher proportion of unsaturated fatty acids in the brain of male mice than in the brain of females. In addition, the expression of enzymes involved in CL de novo and recycling synthetic pathways is higher in males. Most of these sex differences are abolished by the neonatal androgenisation of females, suggesting a role for testosterone in the generation of sex differences in brain CL. The regulation of brain CL by gonadal hormones may be linked to their homeostatic and protective actions in neural cells, as well as the manifestation of sex differences in neurodegenerative disorders.
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Affiliation(s)
- Estefania Acaz-Fonseca
- Instituto Cajal-CSIC, Madrid, Spain
- Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | | | - Luis Miguel Garcia-Segura
- Instituto Cajal-CSIC, Madrid, Spain
- Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Mariana Astiz
- Institute of Neurobiology, Center of Brain Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Germany
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9
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Abstract
X-ray crystallographic analyses of mitochondrial cytochrome c oxidase (CcO) have been based on its dimeric form. Recent cryo-electron microscopy structures revealed that CcO exists in its monomeric form in the respiratory supercomplex. This study, using amphipol-stabilized CcO, shows that the activity of monomer is higher than that of the dimer. The crystal structure of monomer determined here shows that the local structure of one of the proton transfer pathways differs from that in the dimer. The crystal structure also shows that cardiolipins are located at the interface region in the supercomplex. Taken together, these results suggest that CcO in the monomeric state, dimeric state, and supercomplex state depending on cardiolipins are involved in regulation of respiratory electron transport. Cytochrome c oxidase (CcO), a membrane enzyme in the respiratory chain, catalyzes oxygen reduction by coupling electron and proton transfer through the enzyme with a proton pump across the membrane. In all crystals reported to date, bovine CcO exists as a dimer with the same intermonomer contacts, whereas CcOs and related enzymes from prokaryotes exist as monomers. Recent structural analyses of the mitochondrial respiratory supercomplex revealed that CcO monomer associates with complex I and complex III, indicating that the monomeric state is functionally important. In this study, we prepared monomeric and dimeric bovine CcO, stabilized using amphipol, and showed that the monomer had high activity. In addition, using a newly synthesized detergent, we determined the oxidized and reduced structures of monomer with resolutions of 1.85 and 1.95 Å, respectively. Structural comparison of the monomer and dimer revealed that a hydrogen bond network of water molecules is formed at the entry surface of the proton transfer pathway, termed the K-pathway, in monomeric CcO, whereas this network is altered in dimeric CcO. Based on these results, we propose that the monomer is the activated form, whereas the dimer can be regarded as a physiological standby form in the mitochondrial membrane. We also determined phospholipid structures based on electron density together with the anomalous scattering effect of phosphorus atoms. Two cardiolipins are found at the interface region of the supercomplex. We discuss formation of the monomeric CcO, dimeric CcO, and supercomplex, as well as their role in regulation of CcO activity.
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10
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Paradies G, Paradies V, Ruggiero FM, Petrosillo G. Role of Cardiolipin in Mitochondrial Function and Dynamics in Health and Disease: Molecular and Pharmacological Aspects. Cells 2019; 8:cells8070728. [PMID: 31315173 PMCID: PMC6678812 DOI: 10.3390/cells8070728] [Citation(s) in RCA: 230] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 07/12/2019] [Accepted: 07/14/2019] [Indexed: 12/12/2022] Open
Abstract
In eukaryotic cells, mitochondria are involved in a large array of metabolic and bioenergetic processes that are vital for cell survival. Phospholipids are the main building blocks of mitochondrial membranes. Cardiolipin (CL) is a unique phospholipid which is localized and synthesized in the inner mitochondrial membrane (IMM). It is now widely accepted that CL plays a central role in many reactions and processes involved in mitochondrial function and dynamics. Cardiolipin interacts with and is required for optimal activity of several IMM proteins, including the enzyme complexes of the electron transport chain (ETC) and ATP production and for their organization into supercomplexes. Moreover, CL plays an important role in mitochondrial membrane morphology, stability and dynamics, in mitochondrial biogenesis and protein import, in mitophagy, and in different mitochondrial steps of the apoptotic process. It is conceivable that abnormalities in CL content, composition and level of oxidation may negatively impact mitochondrial function and dynamics, with important implications in a variety of pathophysiological situations and diseases. In this review, we focus on the role played by CL in mitochondrial function and dynamics in health and diseases and on the potential of pharmacological modulation of CL through several agents in attenuating mitochondrial dysfunction.
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Affiliation(s)
- Giuseppe Paradies
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70125 Bari, Italy.
| | | | - Francesca M Ruggiero
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, 70125 Bari, Italy
| | - Giuseppe Petrosillo
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), National Research Council (CNR), 70126 Bari, Italy.
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11
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Semba RD, Moaddel R, Zhang P, Ramsden CE, Ferrucci L. Tetra-linoleoyl cardiolipin depletion plays a major role in the pathogenesis of sarcopenia. Med Hypotheses 2019; 127:142-149. [PMID: 31088638 DOI: 10.1016/j.mehy.2019.04.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 04/16/2019] [Indexed: 12/25/2022]
Abstract
Sarcopenia, the progressive loss of muscle mass, strength, and physical performance that occurs during aging, is highly prevalent among the elderly. Sarcopenia increases the risk of falls, disability, and death. The biological basis for sarcopenia is not well understood. There are no specific preventive or therapeutic strategies for sarcopenia except exercise. The elucidation of biological pathways and identification of therapeutic targets for treating or preventing sarcopenia remain a high priority in aging research. Mitochondria play a critical role in skeletal muscle by providing energy in the form of ATP, regulation of signaling, calcium homeostasis, autophagy, and other functions. Cardiolipin, a unique dimeric phospholipid specific to mitochondria and an essential component of mitochondrial membranes, is involved in mitochondrial protein transport, maintaining structural organization of mitochondrial membranes, cellular signaling, regulating enzymes involved in β-oxidation of fatty acids, and facilitating normal electron transport chain (ETC) function and generation of ATP. The fatty acid species composition of cardiolipin is critical to mitochondrial bioenergetics, as cardiolipin affects membrane biophysical properties, binds and stabilizes ETC protein complexes, and shapes the curvature of the mitochondrial cristae. Tetra-linoleoyl cardiolipin (18:2)4 comprises ∼80% of cardiolipin in mitochondria in normal human skeletal and cardiac muscle and is optimal for effective ETC function and ATP generation. Aging is associated with a decrease in cardiolipin content, decrease in tetra-linoleoyl cardiolipin (18:2)4 and replacement of linoleic acid (18:2) with other fatty acids in cardiolipin composition, decline of ETC function, and increased generation of reactive oxygen species in muscle. Together, these findings from the literature prompt the hypothesis that depletion of the cardiolipin (18:2)4 species may be at the root of mitochondrial dysfunction with aging, in turn leading to sarcopenia. Corroboration of the tetra-linoleoyl cardiolipin depletion hypothesis suggests new leads for the prevention and treatment of sarcopenia by enhancing the biosynthesis, accretion, and integrity of tetra-linoleoyl cardiolipin.
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Affiliation(s)
- Richard D Semba
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, United States.
| | - Ruin Moaddel
- National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
| | - Pingbo Zhang
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Christopher E Ramsden
- National Institute on Aging, National Institutes of Health, Baltimore, MD, United States; National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, United States
| | - Luigi Ferrucci
- National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
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12
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Paradies G, Paradies V, Ruggiero FM, Petrosillo G. Mitochondrial bioenergetics and cardiolipin alterations in myocardial ischemia-reperfusion injury: implications for pharmacological cardioprotection. Am J Physiol Heart Circ Physiol 2018; 315:H1341-H1352. [PMID: 30095969 DOI: 10.1152/ajpheart.00028.2018] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Mitochondrial dysfunction plays a central role in myocardial ischemia-reperfusion (I/R) injury. Increased reactive oxygen species production, impaired electron transport chain activity, aberrant mitochondrial dynamics, Ca2+ overload, and opening of the mitochondrial permeability transition pore have been proposed as major contributory factors to mitochondrial dysfunction during myocardial I/R injury. Cardiolipin (CL), a mitochondria-specific phospholipid, plays a pivotal role in multiple mitochondrial bioenergetic processes, including respiration and energy conversion, in mitochondrial morphology and dynamics as well as in several steps of the apoptotic process. Changes in CL levels, species composition, and degree of oxidation may have deleterious consequences for mitochondrial function with important implications in a variety of pathophysiological conditions, including myocardial I/R injury. In this review, we focus on the role played by CL alterations in mitochondrial dysfunction in myocardial I/R injury. Pharmacological strategies to prevent myocardial injury during I/R targeting mitochondrial CL are also examined.
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Affiliation(s)
- Giuseppe Paradies
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari , Bari , Italy
| | | | - Francesca Maria Ruggiero
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari , Bari , Italy
| | - Giuseppe Petrosillo
- Institute of Biomembranes, Bioenergetics, and Molecular Biotechnologies, National Research Council , Bari , Italy
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13
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The folding, stability and function of lactose permease differ in their dependence on bilayer lipid composition. Sci Rep 2017; 7:13056. [PMID: 29026149 PMCID: PMC5638818 DOI: 10.1038/s41598-017-13290-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 09/19/2017] [Indexed: 11/22/2022] Open
Abstract
Lipids play key roles in Biology. Mechanical properties of the lipid bilayer influence their neighbouring membrane proteins, however it is unknown whether different membrane protein properties have the same dependence on membrane mechanics, or whether mechanics are tuned to specific protein processes of the protein. We study the influence of lipid lateral pressure and electrostatic effects on the in vitro reconstitution, folding, stability and function of a representative of the ubiquitous major facilitator transporter superfamily, lactose permease. Increasing the outward chain lateral pressure in the bilayer, through addition of lamellar phosphatidylethanolamine lipids, lowers lactose permease folding and reconstitution yields but stabilises the folded state. The presence of phosphatidylethanolamine is however required for correct folding and function. An increase in headgroup negative charge through the addition of phosphatidylglycerol lipids favours protein reconstitution but is detrimental to topology and function. Overall the in vitro folding, reconstitution, topology, stability and function of lactose permease are found to have different dependences on bilayer composition. A regime of lipid composition is found where all properties are favoured, even if suboptimal. This lays ground rules for rational control of membrane proteins in nanotechnology and synthetic biology by manipulating global bilayer properties to tune membrane protein behaviour.
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14
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Musatov A, Sedlák E. Role of cardiolipin in stability of integral membrane proteins. Biochimie 2017; 142:102-111. [PMID: 28842204 DOI: 10.1016/j.biochi.2017.08.013] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 08/21/2017] [Indexed: 01/13/2023]
Abstract
Cardiolipin (CL) is a unique phospholipid with a dimeric structure having four acyl chains and two phosphate groups found almost exclusively in certain membranes of bacteria and of mitochondria of eukaryotes. CL interacts with numerous proteins and has been implicated in function and stabilization of several integral membrane proteins (IMPs). While both functional and stabilization roles of CL in IMPs has been generally acknowledged, there are, in fact, only limited number of quantitative analysis that support this function of CL. This is likely caused by relatively complex determination of parameters characterizing stability of IMPs and particularly intricate assessment of role of specific phospholipids such as CL in IMPs stability. This review aims to summarize quantitative findings regarding stabilization role of CL in IMPs reported up to now.
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Affiliation(s)
- Andrej Musatov
- Department of Biophysics, Institute of Experimental Physics Slovak Academy of Sciences, Watsonova 47, 040 01 Košice, Slovakia.
| | - Erik Sedlák
- Centre for Interdisciplinary Biosciences, P.J. Šafárik University, Jesenná 5, 040 01 Košice, Slovakia.
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15
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Dimer interface of bovine cytochrome c oxidase is influenced by local posttranslational modifications and lipid binding. Proc Natl Acad Sci U S A 2016; 113:8230-5. [PMID: 27364008 DOI: 10.1073/pnas.1600354113] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Bovine cytochrome c oxidase is an integral membrane protein complex comprising 13 protein subunits and associated lipids. Dimerization of the complex has been proposed; however, definitive evidence for the dimer is lacking. We used advanced mass spectrometry methods to investigate the oligomeric state of cytochrome c oxidase and the potential role of lipids and posttranslational modifications in its subunit interfaces. Mass spectrometry of the intact protein complex revealed that both the monomer and the dimer are stabilized by large lipid entities. We identified these lipid species from the purified protein complex, thus implying that they interact specifically with the enzyme. We further identified phosphorylation and acetylation sites of cytochrome c oxidase, located in the peripheral subunits and in the dimer interface, respectively. Comparing our phosphorylation and acetylation sites with those found in previous studies of bovine, mouse, rat, and human cytochrome c oxidase, we found that whereas some acetylation sites within the dimer interface are conserved, suggesting a role for regulation and stabilization of the dimer, phosphorylation sites were less conserved and more transient. Our results therefore provide insights into the locations and interactions of lipids with acetylated residues within the dimer interface of this enzyme, and thereby contribute to a better understanding of its structure in the natural membrane. Moreover dimeric cytochrome c oxidase, comprising 20 transmembrane, six extramembrane subunits, and associated lipids, represents the largest integral membrane protein complex that has been transferred via electrospray intact into the gas phase of a mass spectrometer, representing a significant technological advance.
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Sedlák E, Varhač R, Musatov A, Robinson NC. The kinetic stability of cytochrome C oxidase: effect of bound phospholipid and dimerization. Biophys J 2016; 107:2941-2949. [PMID: 25517159 DOI: 10.1016/j.bpj.2014.10.055] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/14/2014] [Accepted: 10/22/2014] [Indexed: 12/21/2022] Open
Abstract
Thermally induced transitions of the 13-subunit integral membrane protein bovine cytochrome c oxidase (CcO) have been studied by differential scanning calorimetry (DSC) and circular dichroism (CD). Thermal denaturation of dodecyl maltoside solubilized CcO proceeds in two consecutive, irreversible, kinetically driven steps with the apparent transition temperatures at ∼ 51°C and ∼ 61°C (5μM CcO at scan rate of 1.5 K/min). The thermal denaturation data were analyzed according to the Lyubarev and Kurganov model of two consecutive irreversible steps. However, because of the limitation of the model to describe the complex mechanism of the thermal denaturation of CcO, the obtained results were utilized only for comparison purposes of kinetic stabilities of CcO under specific protein concentration (5μM) and scan rate (1.5 K/min). This enabled us to show that both the amphiphilic environment and the self-association state of CcO affect its kinetic stability. Kinetic stabilities of both steps are significantly decreased when all of the phospholipids are removed from CcO by phospholipase A2 (the half-life decreases at 37°C). Conversely, dimerization of CcO induced by sodium cholate significantly increases its kinetic stability of only the first step (the half-life increases at 37°C). Protein concentration-dependent nonspecific oligomerization also indicate mild stabilization of CcO. Both, reversed-phase high-performance liquid chromatography (HPLC) and SDS-PAGE subunit analysis reveal that the first step of thermal denaturation involves dissociation of subunits III, VIa, VIb, and VIIa, whereas the second step is less well defined and most likely involves global unfold and aggregation of the remaining subunits. Electron transport activity of CcO decreases in a sigmoidal manner during the first transition and this dependence is very well described by kinetic parameters for the first step of the thermal transition. Therefore, dissociation of subunit III and/or VIIa is responsible for temperature-induced inactivation of CcO because VIa and VIb can be removed from CcO without affecting the enzyme activity. These results demonstrate an important role of tightly bound phospholipids and oligomeric state (particularly the dimeric form) of CcO for kinetic stability of the protein.
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Affiliation(s)
- Erik Sedlák
- Department of Biochemistry, The University of Texas Health Science Center, San Antonio, Texas.
| | - Rastislav Varhač
- Department of Biochemistry, The University of Texas Health Science Center, San Antonio, Texas
| | - Andrej Musatov
- Department of Biochemistry, The University of Texas Health Science Center, San Antonio, Texas
| | - Neal C Robinson
- Department of Biochemistry, The University of Texas Health Science Center, San Antonio, Texas
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Rak M, Bénit P, Chrétien D, Bouchereau J, Schiff M, El-Khoury R, Tzagoloff A, Rustin P. Mitochondrial cytochrome c oxidase deficiency. Clin Sci (Lond) 2016; 130:393-407. [PMID: 26846578 PMCID: PMC4948581 DOI: 10.1042/cs20150707] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
As with other mitochondrial respiratory chain components, marked clinical and genetic heterogeneity is observed in patients with a cytochrome c oxidase deficiency. This constitutes a considerable diagnostic challenge and raises a number of puzzling questions. So far, pathological mutations have been reported in more than 30 genes, in both mitochondrial and nuclear DNA, affecting either structural subunits of the enzyme or proteins involved in its biogenesis. In this review, we discuss the possible causes of the discrepancy between the spectacular advances made in the identification of the molecular bases of cytochrome oxidase deficiency and the lack of any efficient treatment in diseases resulting from such deficiencies. This brings back many unsolved questions related to the frequent delay of clinical manifestation, variable course and severity, and tissue-involvement often associated with these diseases. In this context, we stress the importance of studying different models of these diseases, but also discuss the limitations encountered in most available disease models. In the future, with the possible exception of replacement therapy using genes, cells or organs, a better understanding of underlying mechanism(s) of these mitochondrial diseases is presumably required to develop efficient therapy.
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Affiliation(s)
- Malgorzata Rak
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
| | - Paule Bénit
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
| | - Dominique Chrétien
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
| | - Juliette Bouchereau
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
| | - Manuel Schiff
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Reference Center for Inherited Metabolic Diseases, Hôpital Robert Debré, Assistance Publique-Hôpitaux de Paris, 48 Boulevard Sérurier, 75019 Paris, France
| | - Riyad El-Khoury
- American University of Beirut Medical Center, Department of Pathology and Laboratory Medicine, Cairo Street, Hamra, Beirut, Lebanon
| | - Alexander Tzagoloff
- Biological Sciences Department, Columbia University, New York, NY 10027, U.S.A
| | - Pierre Rustin
- Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1141, Hôpital Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France Faculté de Médecine Denis Diderot, Université Paris Diderot-Paris 7, Site Robert Debré, 48 Boulevard Sérurier, 75019 Paris, France
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Musatov A, Varhač R, Hosler JP, Sedlák E. Delipidation of cytochrome c oxidase from Rhodobacter sphaeroides destabilizes its quaternary structure. Biochimie 2016; 125:23-31. [PMID: 26923069 DOI: 10.1016/j.biochi.2016.02.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 02/23/2016] [Indexed: 11/28/2022]
Abstract
Delipidation of detergent-solubilized cytochrome c oxidase isolated from Rhodobacter sphaeroides (Rbs-CcO) has no apparent structural and/or functional effect on the protein, however affects its resistance against thermal or chemical denaturation. Phospholipase A2 (PLA2) hydrolysis of phospholipids that are co-purified with the enzyme removes all but two tightly bound phosphatidylethanolamines. Replacement of the removed phospholipids with nonionic detergent decreases both thermal stability of the enzyme and its resilience against the effect of chemical denaturants such as urea. In contrast to nondelipidated Rbs-CcO, the enzymatic activity of PLA2-treated Rbs-CcO is substantially diminished after exposure to high (>4 M) urea concentration at room temperature without an alteration of its secondary structure. Absorbance spectroscopy and sedimentation velocity experiments revealed a strong correlation between intact tertiary structure of heme regions and quaternary structure, respectively, and the enzymatic activity of the protein. We concluded that phospholipid environment of Rbs-CcO has the protective role for stability of its tertiary and quaternary structures.
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Affiliation(s)
- Andrej Musatov
- Department of Biochemistry, The University of Texas Health Science Center, San Antonio, TX 78229-3900, USA; Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 04001 Košice, Slovakia.
| | - Rastislav Varhač
- Department of Biochemistry, The University of Texas Health Science Center, San Antonio, TX 78229-3900, USA; Department of Biochemistry, P.J. Šafárik University, Moyzesova 11, 04001 Košice, Slovakia.
| | - Jonathan P Hosler
- Department of Biochemistry, The University of Mississippi Medical Center, Jackson, MS 39216, USA.
| | - Erik Sedlák
- Department of Biochemistry, The University of Texas Health Science Center, San Antonio, TX 78229-3900, USA; Department of Biochemistry, P.J. Šafárik University, Moyzesova 11, 04001 Košice, Slovakia; Centre for Interdisciplinary Biosciences, P.J. Šafárik University, Jesenná 5, 04001 Košice, Slovakia.
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Gaspard GJ, McMaster CR. Cardiolipin metabolism and its causal role in the etiology of the inherited cardiomyopathy Barth syndrome. Chem Phys Lipids 2015; 193:1-10. [PMID: 26415690 DOI: 10.1016/j.chemphyslip.2015.09.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 09/14/2015] [Accepted: 09/16/2015] [Indexed: 01/11/2023]
Abstract
Cardiolipin (CL) is a phospholipid with many unique characteristics. CL is synthesized in the mitochondria and resides almost exclusively within the mitochondrial inner membrane. Unlike most phospholipids that have two fatty acyl chains, CL possesses four fatty acyl chains resulting in unique biophysical characteristics that impact several biological processes including membrane fission and fusion. In addition, several proteins directly bind CL including proteins within the electron transport chain, the ADP/ATP carrier, and proteins that mediate mitophagy. Tafazzin is an enzyme that remodels saturated fatty acyl chains within CL to unsaturated fatty acyl chains, loss of function mutations in the TAZ gene encoding tafazzin are causal for the inherited cardiomyopathy Barth syndrome. Cells from Barth syndrome patients as well as several models of Barth have reduced mitochondrial functions including impaired electron transport chain function and increased reactive oxygen species (ROS) production. Mitochondria in cells from Barth syndrome patients, as well as several model organism mimics of Barth syndrome, are large and lack cristae consistent with the recently described role of CL participating in the generation of mitochondrial membrane contact sites. Cells with an inactive TAZ gene have also been shown to have a decreased capacity to undergo mitophagy when faced with stresses such as increased ROS or decreased mitochondrial quality control. This review describes CL metabolism and how defects in CL metabolism cause Barth syndrome, the etiology of Barth syndrome, and known modifiers of Barth syndrome phenotypes some of which could be explored for their amelioration of Barth syndrome in higher organisms.
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Affiliation(s)
- Gerard J Gaspard
- Departments of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS, Canada
| | - Christopher R McMaster
- Departments of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS, Canada; Departments of Pharmacology, Dalhousie University, Halifax, NS, Canada.
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Sedlák E, Robinson NC. Destabilization of the Quaternary Structure of Bovine Heart Cytochrome c Oxidase upon Removal of Tightly Bound Cardiolipin. Biochemistry 2015; 54:5569-77. [PMID: 26284624 DOI: 10.1021/acs.biochem.5b00540] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The quaternary structural stability of cardiolipin-containing (CcO(CL+)) versus CL-free cytochrome c oxidase (CcO(CL-)) was compared using structural perturbants as probes. Exposure to increasing concentrations of urea or guanidinium chloride causes sequential dissociation of five subunits from CcO(CL+) in the order VIa and VIb, followed by III and VIIa, and ultimately Vb. Removal of CL from CcO destabilizes the association of each of these five subunits with the core of CcO. Subunits VIa and VIb spontaneously dissociate from CcO(CL-) even in the absence of denaturant and are no longer present after purification of the CL-free 11-subunit complex by ion exchange chromatography. The other 11 subunits remain associated in a partially active complex, but the association of subunits III, VIIa, and Vb is weakened; i.e., the midpoints for the subunit dissociation curves are each shifted to a lower perturbant concentration (lower by 1.1-1.7 M urea; lower by 0.3-0.4 M GdmCl). This corresponds to a decrease of ∼9 kJ in the Gibbs free association energy for each of these subunits when CL is removed from CcO. With either CcO(CL+) or CcO(CL-), loss of enzymatic activity occurs coincident with dissociation of subunits III and VIIa. The loss of activity is irreversible, and reactivation of CcO(CL-) by exogenous CL occurs only if both subunits remain associated with the core of CcO. Inclusion of sulfate anions stabilizes the association of VIIa more than III, resulting in a slight separation of the urea-induced dissociation curves. In this case, activity loss correlates much better with dissociation of subunit VIIa than III. We conclude that (1) bound cardiolipin is an important stabilizing factor in the quaternary structure of CcO and (2) association of subunit VIIa (possibly together with subunit III) is critical for functional CL binding and full electron-transfer activity of CcO.
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Affiliation(s)
- Erik Sedlák
- Department of Biochemistry, The University of Texas Health Science Center , San Antonio, Texas 78229-3900, United States
| | - Neal C Robinson
- Department of Biochemistry, The University of Texas Health Science Center , San Antonio, Texas 78229-3900, United States
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Vitale R, Angelini R, Lobasso S, Capitanio G, Ludwig B, Corcelli A. MALDI-TOF MS lipid profiles of cytochrome c oxidases: cardiolipin is not an essential component of the Paracoccus denitrificans oxidase. Biochemistry 2015; 54:1144-50. [PMID: 25565128 DOI: 10.1021/bi5008468] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Lipids of cytochrome c oxidase (COX) of Paracoccus denitrificans have been identified by MALDI-TOF MS direct analyses of isolated protein complexes, avoiding steps of lipid extraction or chromatographic separation. Two different COX preparations have been considered in this study: the enzyme core consisting of subunits I and II (COX 2-SU) and the complete complex comprising all four subunits (COX 4-SU). In addition, MALDI-TOF MS lipid profiles of bacterial COX are also compared with those of the isolated mitochondrial COX and bacterial bc1 complex. We show that the main lipids associated with bacterial COX 4-SU are phosphatidylglycerol (PG) and phosphatidylcholine (PC), and minor amounts of cardiolipin (CL). PG and PC are absent in the COX 2-SU preparation lacking subunits III and IV, whereas CL is still present. Quantitative analyses indicate that at variance from mitochondrial COX, cardiolipin is present in substoichiometric amounts in bacterial COX, at a CL:COX molar ratio of ∼1:10. We conclude that bacterial COX does not require CL for structure or its activity.
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Affiliation(s)
- Rita Vitale
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, University of Bari "A. Moro" , 70124 Bari, Italy
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