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Fujii J, Imai H. Oxidative Metabolism as a Cause of Lipid Peroxidation in the Execution of Ferroptosis. Int J Mol Sci 2024; 25:7544. [PMID: 39062787 PMCID: PMC11276677 DOI: 10.3390/ijms25147544] [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: 06/28/2024] [Revised: 07/07/2024] [Accepted: 07/08/2024] [Indexed: 07/28/2024] Open
Abstract
Ferroptosis is a type of nonapoptotic cell death that is characteristically caused by phospholipid peroxidation promoted by radical reactions involving iron. Researchers have identified many of the protein factors that are encoded by genes that promote ferroptosis. Glutathione peroxidase 4 (GPX4) is a key enzyme that protects phospholipids from peroxidation and suppresses ferroptosis in a glutathione-dependent manner. Thus, the dysregulation of genes involved in cysteine and/or glutathione metabolism is closely associated with ferroptosis. From the perspective of cell dynamics, actively proliferating cells are more prone to ferroptosis than quiescent cells, which suggests that radical species generated during oxygen-involved metabolism are responsible for lipid peroxidation. Herein, we discuss the initial events involved in ferroptosis that dominantly occur in the process of energy metabolism, in association with cysteine deficiency. Accordingly, dysregulation of the tricarboxylic acid cycle coupled with the respiratory chain in mitochondria are the main subjects here, and this suggests that mitochondria are the likely source of both radical electrons and free iron. Since not only carbohydrates, but also amino acids, especially glutamate, are major substrates for central metabolism, dealing with nitrogen derived from amino groups also contributes to lipid peroxidation and is a subject of this discussion.
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Affiliation(s)
- Junichi Fujii
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Yamagata 990-9585, Japan
| | - Hirotaka Imai
- Laboratory of Hygienic Chemistry, School of Pharmaceutical Sciences, Kitasato University, Tokyo 108-8641, Japan
- Medical Research Laboratories, School of Pharmaceutical Sciences, Kitasato University, Tokyo 108-8641, Japan
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2
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Dobbelaar E, Rauber C, Bonck T, Kelm H, Schmitz M, de Waal Malefijt ME, Klein JEMN, Krüger HJ. Combining Structural with Functional Model Properties in Iron Synthetic Analogue Complexes for the Active Site in Rabbit Lipoxygenase. J Am Chem Soc 2021; 143:13145-13155. [PMID: 34383499 DOI: 10.1021/jacs.1c04422] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Iron complexes that model the structural and functional properties of the active iron site in rabbit lipoxygenase are described. The ligand sphere of the mononuclear pseudo-octahedral cis-(carboxylato)(hydroxo)iron(III) complex, which is completed by a tetraazamacrocyclic ligand, reproduces the first coordination shell of the active site in the enzyme. In addition, two corresponding iron(II) complexes are presented that differ in the coordination of a water molecule. In their structural and electronic properties, both the (hydroxo)iron(III) and the (aqua)iron(II) complex reflect well the only two essential states found in the enzymatic mechanism of peroxidation of polyunsaturated fatty acids. Furthermore, the ferric complex is shown to undergo hydrogen atom abstraction reactions with O-H and C-H bonds of suitable substrates, and the bond dissociation free energy of the coordinated water ligand of the ferrous complex is determined to be 72.4 kcal·mol-1. Theoretical investigations of the reactivity support a concerted proton-coupled electron transfer mechanism in close analogy to the initial step in the enzymatic mechanism. The propensity of the (hydroxo)iron(III) complex to undergo H atom abstraction reactions is the basis for its catalytic function in the aerobic peroxidation of 2,4,6-tri(tert-butyl)phenol and its role as a radical initiator in the reaction of dihydroanthracene with oxygen.
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Affiliation(s)
- Emiel Dobbelaar
- Department of Chemistry, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Christian Rauber
- Department of Chemistry, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Thorsten Bonck
- Department of Chemistry, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Harald Kelm
- Department of Chemistry, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Markus Schmitz
- Department of Chemistry, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Matina Eloïse de Waal Malefijt
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 9, 9747 AG Groningen, The Netherlands
| | - Johannes E M N Klein
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, Faculty of Science and Engineering, University of Groningen, Nijenborgh 9, 9747 AG Groningen, The Netherlands
| | - Hans-Jörg Krüger
- Department of Chemistry, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany
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3
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C. S. S, K. G. A, V. V, A. S, M. H. Designing of enzyme inhibitors based on active site specificity: lessons from methyl gallate and its lipoxygenase inhibitory profile. J Recept Signal Transduct Res 2018; 38:256-265. [DOI: 10.1080/10799893.2018.1478856] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Sharanya C. S.
- Inter University Centre for Bioscience and Department of Biotechnology & Microbiology, Kannur University, Thalassery Campus, Palayad, India
| | - Arun K. G.
- Inter University Centre for Bioscience and Department of Biotechnology & Microbiology, Kannur University, Thalassery Campus, Palayad, India
| | - Vijaytha V.
- Inter University Centre for Bioscience and Department of Biotechnology & Microbiology, Kannur University, Thalassery Campus, Palayad, India
| | - Sabu A.
- Inter University Centre for Bioscience and Department of Biotechnology & Microbiology, Kannur University, Thalassery Campus, Palayad, India
| | - Haridas M.
- Inter University Centre for Bioscience and Department of Biotechnology & Microbiology, Kannur University, Thalassery Campus, Palayad, India
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4
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Ivanov I, Kuhn H, Heydeck D. Structural and functional biology of arachidonic acid 15-lipoxygenase-1 (ALOX15). Gene 2015; 573:1-32. [PMID: 26216303 PMCID: PMC6728142 DOI: 10.1016/j.gene.2015.07.073] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/26/2015] [Accepted: 07/21/2015] [Indexed: 12/14/2022]
Abstract
Lipoxygenases (LOX) form a family of lipid peroxidizing enzymes, which have been implicated in a number of physiological processes and in the pathogenesis of inflammatory, hyperproliferative and neurodegenerative diseases. They occur in two of the three domains of terrestrial life (bacteria, eucarya) and the human genome involves six functional LOX genes, which encode for six different LOX isoforms. One of these isoforms is ALOX15, which has first been described in rabbits in 1974 as enzyme capable of oxidizing membrane phospholipids during the maturational breakdown of mitochondria in immature red blood cells. During the following decades ALOX15 has extensively been characterized and its biological functions have been studied in a number of cellular in vitro systems as well as in various whole animal disease models. This review is aimed at summarizing the current knowledge on the protein-chemical, molecular biological and enzymatic properties of ALOX15 in various species (human, mouse, rabbit, rat) as well as its implication in cellular physiology and in the pathogenesis of various diseases.
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Affiliation(s)
- Igor Ivanov
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Hartmut Kuhn
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany.
| | - Dagmar Heydeck
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
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5
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Probing the range of applicability of structure- and energy-adjusted QM/MM link bonds. J Comput Chem 2015; 36:1929-39. [DOI: 10.1002/jcc.24032] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 06/24/2015] [Accepted: 07/13/2015] [Indexed: 12/18/2022]
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Horn T, Adel S, Schumann R, Sur S, Kakularam KR, Polamarasetty A, Redanna P, Kuhn H, Heydeck D. Evolutionary aspects of lipoxygenases and genetic diversity of human leukotriene signaling. Prog Lipid Res 2014; 57:13-39. [PMID: 25435097 PMCID: PMC7112624 DOI: 10.1016/j.plipres.2014.11.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 11/17/2014] [Accepted: 11/19/2014] [Indexed: 12/14/2022]
Abstract
Leukotrienes are pro-inflammatory lipid mediators, which are biosynthesized via the lipoxygenase pathway of the arachidonic acid cascade. Lipoxygenases form a family of lipid peroxidizing enzymes and human lipoxygenase isoforms have been implicated in the pathogenesis of inflammatory, hyperproliferative (cancer) and neurodegenerative diseases. Lipoxygenases are not restricted to humans but also occur in a large number of pro- and eucaryotic organisms. Lipoxygenase-like sequences have been identified in the three domains of life (bacteria, archaea, eucarya) but because of lacking functional data the occurrence of catalytically active lipoxygenases in archaea still remains an open question. Although the physiological and/or pathophysiological functions of various lipoxygenase isoforms have been studied throughout the last three decades there is no unifying concept for the biological importance of these enzymes. In this review we are summarizing the current knowledge on the distribution of lipoxygenases in living single and multicellular organisms with particular emphasis to higher vertebrates and will also focus on the genetic diversity of enzymes and receptors involved in human leukotriene signaling.
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Affiliation(s)
- Thomas Horn
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany; Department of Chemistry and Biochemistry, University of California - Santa Cruz, 1156 High Street, 95064 Santa Cruz, USA
| | - Susan Adel
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
| | - Ralf Schumann
- Institute of Microbiology, Charité - University Medicine Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Saubashya Sur
- Institute of Microbiology, Charité - University Medicine Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Kumar Reddy Kakularam
- Department of Animal Sciences, School of Life Science, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India
| | - Aparoy Polamarasetty
- School of Life Sciences, University of Himachal Pradesh, Dharamshala, Himachal Pradesh 176215, India
| | - Pallu Redanna
- Department of Animal Sciences, School of Life Science, University of Hyderabad, Gachibowli, Hyderabad 500046, Telangana, India; National Institute of Animal Biotechnology, Miyapur, Hyderabad 500049, Telangana, India
| | - Hartmut Kuhn
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany.
| | - Dagmar Heydeck
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, CCO-Building, Virchowweg 6, D-10117 Berlin, Germany
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7
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Abstract
The nature of the cytosolic iron pool remains largely uncharacterized, although a range of candidate ligands and chaperones have been proposed. Herein an overview is presented of cytosolic non heme and non iron-sulphur cluster protein iron binding sites and the influence of ligands on the redox activity of iron. This analysis leads to the concept of iron(II) glutathione functioning as the labile cytosolic iron pool and offers a means for the selection of iron over manganese in subsequent incorporation into a wide range of iron-dependent enzymes and electron transfer proteins. Glutathione and glutathione-binding glutaredoxins play a critical role in iron sulfur cluster synthesis and Fe(II)GS (iron(II) coordinated by the thiol function of glutathione) is a suitable iron donor for this biosynthetic route. Significantly, both glutathione and glutaredoxins are universally distributed and thus a controlling influence of glutathione on intracellular iron trafficking is likely to be a common feature of the majority of living organisms.
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Affiliation(s)
- Robert C Hider
- Institute of Pharmaceutical Science, King's College London, Franklin-Wilkins Building, Stamford Street, London SE1 9NH, UK.
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8
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Moin ST, Hofer TS, Sattar R, Ul-Haq Z. Molecular dynamics simulation of mammalian 15S-lipoxygenase with AMBER force field. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2011; 40:715-26. [PMID: 21360129 DOI: 10.1007/s00249-011-0684-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 11/28/2010] [Accepted: 02/04/2011] [Indexed: 01/09/2023]
Abstract
A molecular dynamics simulation study of mononuclear iron 15S-lipoxygenase (15S-LOX) from rabbit reticulocytes was performed to investigate its structure and dynamics; newly developed AMBER force field parameters were employed for the first coordination sphere of the catalytic iron (II). The results obtained from this study demonstrate that the structural features of the catalytic iron coordination site are in good agreement with available data obtained from experiments. The motional flexibility of the N-terminal β-barrel domain is greater than the C-terminal catalytic domain; flexibility was assessed in terms of B-factors and secondary structure calculations. The significant features obtained for the relative motional flexibility of these two domains of 15S-LOX in solution as well as the isolated C-terminal domain were analyzed in terms of radius of gyration and maximum diameter, which correlated well with the structural flexibility of 15-lipoxygenase-1 in solution as probed by small-angle X-ray scattering. The motional flexibility indicates interdomain motion between the N-terminal β-barrel and the C-terminal catalytic domain; this was further verified by the evaluation of central bending in the solvated LOX molecule, which identified an unstructured stretch of amino acids as the interdomain linker. The average bending angle confirmed significant central bending between these two domains, which was linked to the high degree of motional freedom of the N-terminal β-barrel domain in aqueous solutions. This can be considered to have biological relevance for membrane binding as well as for regulating the catalytic domain.
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Affiliation(s)
- Syed Tarique Moin
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan
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9
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Ivanov I, Heydeck D, Hofheinz K, Roffeis J, O'Donnell VB, Kuhn H, Walther M. Molecular enzymology of lipoxygenases. Arch Biochem Biophys 2010; 503:161-74. [PMID: 20801095 DOI: 10.1016/j.abb.2010.08.016] [Citation(s) in RCA: 405] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 08/19/2010] [Accepted: 08/20/2010] [Indexed: 10/19/2022]
Abstract
Lipoxygenases (LOXs) are lipid peroxidizing enzymes, implicated in the pathogenesis of inflammatory and hyperproliferative diseases, which represent potential targets for pharmacological intervention. Although soybean LOX1 was discovered more than 60years ago, the structural biology of these enzymes was not studied until the mid 1990s. In 1993 the first crystal structure for a plant LOX was solved and following this protein biochemistry and molecular enzymology became major fields in LOX research. This review focuses on recent developments in molecular enzymology of LOXs and summarizes our current understanding of the structural basis of LOX catalysis. Various hypotheses explaining the reaction specificity of different isoforms are critically reviewed and their pros and cons briefly discussed. Moreover, we summarize the current knowledge of LOX evolution by profiling the existence of LOX-related genomic sequences in the three kingdoms of life. Such sequences are found in eukaryotes and bacteria but not in archaea. Although the biological role of LOXs in lower organisms is far from clear, sequence data suggests that this enzyme family might have evolved shortly after the appearance of atmospheric oxygen on earth.
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Affiliation(s)
- Igor Ivanov
- Institute of Biochemistry, University Medicine Berlin - Charité, Germany
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10
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Walther M, Roffeis J, Jansen C, Anton M, Ivanov I, Kuhn H. Structural basis for pH-dependent alterations of reaction specificity of vertebrate lipoxygenase isoforms. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:827-35. [PMID: 19481615 DOI: 10.1016/j.bbalip.2009.05.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Revised: 05/13/2009] [Accepted: 05/21/2009] [Indexed: 11/16/2022]
Abstract
Lipoxygenases have been classified according to their specificity of fatty acid oxygenation and for several plant enzymes pH-dependent alterations in the product patterns have been reported. Assuming that the biological role of mammalian lipoxygenases is based on the formation of specific reaction products, pH-dependent alterations would impact enzymes' functionality. In this study we systematically investigated the pH-dependence of vertebrate lipoxygenases and observed a remarkable stability of the product pattern in the near physiological range for the wild-type enzyme species. Site-directed mutagenesis of selected amino acids and alterations in the substrate concentrations induced a more pronounced pH-dependence of the reaction specificity. For instance, for the V603H mutant of the human 15-lipoxygenase-2 8-lipoxygenation was dominant at acidic pH (65%) whereas 15-H(p)ETE was the major oxygenation product at pH 8. Similarly, the product pattern of the wild-type mouse 8-lipoxygenase was hardly altered in the near physiological pH range but H604F exchange induced strong pH-dependent alterations in the positional specificity. Taken together, our data suggest that the reaction specificities of wild-type vertebrate lipoxygenase isoforms are largely resistant towards pH alterations. However, we found that changes in the assay conditions (low substrate concentration) and introduction/removal of a critical histidine at the active site impact the pH-dependence of reaction specificity for some lipoxygenase isoforms.
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Affiliation(s)
- M Walther
- Institute of Biochemistry, University Medicine Berlin - Charité, Germany.
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11
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Herre S, Schadendorf T, Ivanov I, Herrberger C, Steinle W, Rück-Braun K, Preissner R, Kuhn H. Photoactivation of an Inhibitor of the 12/15‐Lipoxygenase Pathway. Chembiochem 2006; 7:1089-95. [PMID: 16755628 DOI: 10.1002/cbic.200600082] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Lipoxygenases are lipid-peroxidizing enzymes that have been implicated in the pathogenesis of inflammatory diseases and lipoxygenase inhibitors may be developed as anti-inflammatory drugs. Structure comparison with known lipoxygenase inhibitors has suggested that (2Z)-2-(3-benzylidene)-3-oxo-2,3-dihydrobenzo[b]thiophene-7-carboxylic acid methyl ester might inhibit the lipoxygenase pathway but we found that it exhibited only a low inhibitory potency for the pure 12/15-lipoxygenase (IC(50) = 0.7 mM). However, photoactivation, which induces a Z-to-E isomerization of the double bond, strongly augmented the inhibitory potency and an IC(50) value of 0.021 mM was determined for the pure E isomer. Similar isomer-specific differences were observed with the recombinant enzyme and its 12-lipoxygenating Ile418Ala mutant, as well as in intracellular lipoxygenase activity. Structure modeling of the enzyme/inhibitor complex suggested the molecular reasons for this isomer specificity. Since light-induced isomerization may proceed in the skin, such photoreactive compounds might be developed as potential drugs for inflammatory skin diseases.
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Affiliation(s)
- Stephan Herre
- Institute of Chemistry, Technical University Berlin, Germany
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12
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Kuhn H, Saam J, Eibach S, Holzhütter HG, Ivanov I, Walther M. Structural biology of mammalian lipoxygenases: Enzymatic consequences of targeted alterations of the protein structure. Biochem Biophys Res Commun 2005; 338:93-101. [PMID: 16168952 DOI: 10.1016/j.bbrc.2005.08.238] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2005] [Accepted: 08/27/2005] [Indexed: 11/19/2022]
Abstract
Lipoxygenases form a heterogeneous family of lipid peroxidizing enzymes, which have been implicated in the pathogenesis of diseases with major health political relevance (bronchial asthma, atherosclerosis, cancer, and osteoporosis). The crystal structures of one mammalian lipoxygenase and of two plant isoenzymes have been solved and the structural bases of important enzyme properties (reaction specificity, membrane binding, and suicidal inactivation) have been investigated in the past. This review will briefly summarize our current understanding on the structural biology of the most important mammalian lipoxygenase isoforms and will also address selected mechanistic features of the lipoxygenase reaction.
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Affiliation(s)
- Hartmut Kuhn
- Institute of Biochemistry, University Medicine Berlin-Charite, Monbijoustr. 2, 10117 Berlin, Germany.
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Kuhn H, Walther M, Kuban RJ. Mammalian arachidonate 15-lipoxygenases structure, function, and biological implications. Prostaglandins Other Lipid Mediat 2002; 68-69:263-90. [PMID: 12432923 DOI: 10.1016/s0090-6980(02)00035-7] [Citation(s) in RCA: 167] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Lipoxygenases (LOXs) constitute a heterogeneous family of lipid peroxidizing enzymes capable of oxygenating polyunsaturated fatty acids to their corresponding hydroperoxy derivatives. In mammals, LOXs are classified with respect to their positional specificity of arachidonic acid oxygenation into 5-, 8-, 12-, and 15-LOXs. Arachidonate 15-LOXs may be sub-classified into a reticulocyte-type (type-1) and an epidermis-type (type-2) enzyme. Since the leukocyte-type 12-LOXs are very similar to the reticulocyte-type 15-LOXs, these enzymes are designated 12/15-LOXs. Several LOX isoforms, in particular the reticulocyte-type 15-LOX and the human 5-LOX, are well characterized with respect to their structural and functional properties On the other hand, the biological role of most LOX-isozymes including the reticulocyte-type 15-LOC is far from clear. This review is intended to summarize the recent developments in 15-LOX research with particular emphasis to molecular enzymology and regulation of gene expression. In addition, the major hypotheses on the physiological and patho-physiological roles of 15-LOXs will be discussed briefly.
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Affiliation(s)
- Hartmut Kuhn
- Institute of Biochemistry, University Clinics Charité, Humboldt University, Berlin, Germany.
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Kühn H, Borchert A. Regulation of enzymatic lipid peroxidation: the interplay of peroxidizing and peroxide reducing enzymes. Free Radic Biol Med 2002; 33:154-72. [PMID: 12106812 DOI: 10.1016/s0891-5849(02)00855-9] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
For a long time lipid peroxidation has only been considered a deleterious process leading to disruption of biomembranes and thus, to cellular dysfunction. However, when restricted to a certain cellular compartment and tightly regulated, lipid peroxidation may have beneficial effects. Early on during evolution of living organisms special lipid peroxidizing enzymes, called lipoxygenases, appeared and they have been conserved during phylogenesis of plants and animals. In fact, a diverse family of lipoxygenase isoforms has evolved starting from a putative ancient precursor. As with other enzymes, lipoxygenases are regulated on various levels of gene expression and there are endogenous antagonists controlling their cellular activity. Among the currently known mammalian lipoxygenase isoforms only 12/15-lipoxygenases are capable of directly oxygenating ester lipids even when they are bound to membranes and lipoproteins. Thus, these enzymes represent the pro-oxidative part in the cellular metabolism of complex hydroperoxy ester lipids. Its metabolic counterplayer, representing the antioxidative part, appears to be the phospholipid hydroperoxide glutathione peroxidase. This enzyme is unique among glutathione peroxidases because of its capability of reducing ester lipid hydroperoxides. Thus, 12/15-lipoxygenase and phospholipid hydroperoxide glutathione peroxidase constitute a pair of antagonizing enzymes in the metabolism of hydroperoxy ester lipids, and a balanced regulation of the two proteins appears to be of major cell physiological importance. This review is aimed at summarizing the recent developments in the enzymology and molecular biology of 12/15-lipoxygenase and phospholipid hydroperoxide glutathione peroxidase, with emphasis on cytokine-dependent regulation and their regulatory interplay.
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Affiliation(s)
- Hartmut Kühn
- Institute of Biochemistry, University Clinics Charité, Humboldt University, Berlin, Germany.
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15
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Hörnsten L, Su C, Osbourn AE, Hellman U, Oliw EH. Cloning of the manganese lipoxygenase gene reveals homology with the lipoxygenase gene family. EUROPEAN JOURNAL OF BIOCHEMISTRY 2002; 269:2690-7. [PMID: 12047377 DOI: 10.1046/j.1432-1033.2002.02936.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Manganese lipoxygenase was isolated to homogeneity from the take-all fungus, Gaeumannomyces graminis. The C-terminal amino acids and several internal peptides were sequenced, and the information was used to obtain a cDNA probe by RT/PCR. Screening of a genomic library of G. graminis yielded a full-length clone of the Mn-Lipoxygenase gene. cDNA analysis showed that the gene spanned 2.6 kb and contained one intron (133 bp). Northern blot analyses indicated two transcripts (2.7 and 3.1 kb). The deduced amino-acid sequence of the Mn-Lipoxygenase precursor (618 amino acids, 67.7 kDa) could be aligned with mammalian and plant lipoxygenases with 23-28% identity over 350-400 amino-acid residues of the catalytic domains. Lipoxygenases have one water molecule and five amino acids as Fe ligands. These are two histidine residues in the highly conserved 30 amino-acid sequence WLLAK-X15-H-X4-H-X3-E of alpha helix 9, one histidine and usually an asparaine residue in the sequence H-X3-N-X-G of alpha helix 18, and the carboxyl oxygen of the C-terminal isoleucine (or valine) residue. The homologous sequence of alpha helix 9 of Mn-Lipoxygenase [WLLAK-X14-H(294)-X3-H(297)-X3-E] contained two single-amino-acid gaps, but otherwise His294 and His297 aligned with the two His residues, which coordinate iron. Mn-Lipoxygenase [H(478)-X3-N(482)-X-G] could be aligned with the two metal ligands of alpha helix 18, and the C-terminal residue was Val618. We conclude that Mn-Lipoxygenase belongs to the lipoxygenase gene family and that its unique biochemical properties might be related to structural differences in the metal centre and alpha helix 9 of lipoxygenases rather than to the metal ligands.
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Affiliation(s)
- Lena Hörnsten
- Department of Pharmaceutical Biosciences, Uppsala Biomedical Centre, Uppsala, Sweden
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16
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Kayyali R, Porter JB, Liu ZD, Davies NA, Nugent JH, Cooper CE, Hider RC. Structure-function investigation of the interaction of 1- and 2-substituted 3-hydroxypyridin-4-ones with 5-lipoxygenase and ribonucleotide reductase. J Biol Chem 2001; 276:48814-22. [PMID: 11602611 DOI: 10.1074/jbc.m109551200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The structural and physiochemical properties of 3-hydroxypyridin-4-one chelators (HPOs) which influence inhibition of the iron-containing metalloenzymes ribonucleotide reductase (RR) and 5-lipoxygenase (5-LO) have been investigated. HPOs with substituents at the 1- and 2-positions of the pyridinone ring have been synthesized, and their inhibitory properties compared with those of desferrioxamine (DFO). Varying the alkyl substituents does not affect the affinity constant of these ligands for iron(III), but permits a systematic investigation of the effect of hydrophobicity and molecular shape on inhibitory properties. The inhibition of RR was monitored, indirectly by measuring tritiated thymidine incorporation into DNA and directly by the quantification of the EPR signal of the enzyme tyrosyl radical. 5-LO inhibition was examined spectrophotometrically, measuring the rate of linoleic hydroperoxide formation by soybean lipoxygenase. The results indicate that the substituent size introduced at the 2-position of the HPO ring is critical for determining inhibition of both enzymes. Large substituents on the 2-position, introduce a steric factor which interferes with accessibility to the iron centers. These studies have identified chelators such as 1,6-dimethyl-2-(N-4',N-propylsuccinamido)methyl-3-hydroxypyridin-4-one (CP358), which causes only a 10% inhibition of 5-LO after 24 h of incubation at 110 microm IBE (iron-binding equivalents) in comparison to simple dialkyl HPOs such as Deferiprone (CP20) which cause up to 70% inhibition. Using EPR spectroscopy, CP358 inhibits RR at a slower rate than CP20, while chelating intracellular iron(III) at a similar rate, a finding consistent with an indirect inhibition of the tyrosyl radical. However, hepatocellular iron is mobilized at a faster rate by CP358 (P < 0.001). These findings demonstrate that it is possible to design bidentate HPOs which access intracellular iron pools rapidly while inhibiting non-heme iron-containing enzymes relatively slowly, at rates comparable to DFO. It is anticipated that such compounds will possess a superior therapeutic safety margin to currently available bidentate HPOs.
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Affiliation(s)
- R Kayyali
- Department of Clinical Haematology, University College London Medical School, London WC1E 6HX, United Kingdom.
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17
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Hammarberg T, Kuprin S, Rådmark O, Holmgren A. EPR investigation of the active site of recombinant human 5-lipoxygenase: inhibition by selenide. Biochemistry 2001; 40:6371-8. [PMID: 11371199 DOI: 10.1021/bi001595d] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Lipoxygenases are a group of non-heme iron dioxygenases which catalyze the formation of lipid hydroperoxides from unsaturated fatty acids. 5-Lipoxygenase (5LO) is of particular interest for formation of leukotrienes and lipoxins, implicated in inflammatory processes. In this study, electron paramagnetic resonance (EPR) spectroscopy was used to investigate the active site iron of purified recombinant human 5-lipoxygenase (5LO), and to explore the action of selenide on 5LO. After oxidation by lipid hydroperoxides, 5LO exhibited axial EPR spectra typified by a signal at g = 6.2. However, removal of the lipid hydroperoxides, their metabolites, and the solvent ethanol from the samples resulted in a shift to more rhombic EPR spectra (g = 5.17 and g = 9.0). Thus, many features of 5LO and soybean lipoxygenase-1 EPR spectra were similar, indicating similar flexible iron ligand arrangements in these lipoxygenases. Selenide (1.5 microM) showed a strong inhibitory effect on the enzyme activity of 5LO. In EPR, selenide abolished the signal at g = 6.2, typical for enzymatically active 5LO. Lipid hydroperoxide added to selenide-treated 5LO could not reinstate the signal at g = 6.2, indicating an irreversible change of the coordination of the active site iron.
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Affiliation(s)
- T Hammarberg
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
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18
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Mugesh G, du Mont WW, Sies H. Chemistry of biologically important synthetic organoselenium compounds. Chem Rev 2001; 101:2125-79. [PMID: 11710243 DOI: 10.1021/cr000426w] [Citation(s) in RCA: 1247] [Impact Index Per Article: 54.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- G Mugesh
- Institut für Anorganische und Analytische Chemie, Technischen Universität, Postfach 3329, D-38023 Braunschweig, Germany
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19
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Jisaka M, Boeglin WE, Kim RB, Brash AR. Site-Directed Mutagenesis Studies on a Putative Fifth Iron Ligand of Mouse 8S-Lipoxygenase: Retention of Catalytic Activity on Mutation of Serine-558 to Asparagine, Histidine, or Alanine. Arch Biochem Biophys 2001; 386:136-42. [PMID: 11368335 DOI: 10.1006/abbi.2000.2175] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The reported crystal structures of plant and animal lipoxygenases (LOX) show that the nonheme iron in the catalytic domain is ligated by three histidines, the C-terminal isoleucine, and in certain structures also by a fifth iron ligand, an asparagine or histidine residue. Mouse 8-LOX and its homologues (e.g., human 15-LOX-2) are unique in having a serine in place of the usual Asn or His in this fifth position. To investigate the importance of the residue in mouse 8-LOX structure-function, the serine-558 was replaced by asparagine, histidine, or alanine using oligonucleotide-directed mutagenesis. Wild-type mouse 8-LOX and the mutant cDNAs were expressed in HeLa cells infected with vaccinia virus encoding T7 RNA polymerase and their relative lipoxygenase activities assessed by incubation with [14C]arachidonic acid or [14C]linoleic acid followed by HPLC analysis of the products. The Ser558Asn and Ser558His mutants had equivalent or greater activity than wild-type 8-LOX. They also exhibited some 15-LOX activity, indicating that small structural perturbations (in this case to a residue identical in mouse 8-LOX and its 15-LOX-2 homologues) can interchange the positional specificity of these closely related enzymes. Remarkably, the Ser558Ala mutant exhibited significant 8-LOX activity, indicating that this position is not an essential iron ligand in the enzyme. We conclude that mouse 8-LOX is catalytically competent with only four amino acid iron ligands, and that Ser-558 of the wild-type enzyme does not play an essential role in catalysis.
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Affiliation(s)
- M Jisaka
- Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-6602, USA.
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20
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Hughes RK, Lawson DM, Hornostaj AR, Fairhurst SA, Casey R. Mutagenesis and modelling of linoleate-binding to pea seed lipoxygenase. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:1030-40. [PMID: 11179969 DOI: 10.1046/j.1432-1327.2001.01964.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have produced a model to define the linoleate-binding pocket of pea 9/13-lipoxygenase and have validated it by the construction and characterization of eight point mutants. Three of the mutations reduced, to varying degrees, the catalytic centre activity (kcat) of the enzyme with linoleate. In two of the mutants, reductions in turnover were associated with changes in iron-coordination. Multiple sequence alignments of recombinant plant and mammalian lipoxygenases of known positional specificity, and the results from numerous other mutagenesis and modelling studies, have been combined to discuss the possible role of the mutated residues in pea 9/13-lipoxygenase catalysis. A new nomenclature for recombinant plant lipoxygenases based on positional specificity has subsequently been proposed. The null-effect of mutating pea 9/13-lipoxygenase at the equivalent residue to that which controlled dual positional specificity in cucumber 13/9-lipoxygenase, strongly suggests that the mechanisms controlling dual positional specificity in pea 9/13-lipoxygenase and cucumber 13/9-lipoxygenase are different. This was supported from modelling of another isoform of pea lipoxygenase, pea 13/9-lipoxygenase. Dual positional specificity in pea lipoxygenases is more likely to be determined by the degree of penetration of the methyl terminus of linoleate and the volume of the linoleate-binding pocket rather than substrate orientation. A single model for positional specificity, that has proved to be inappropriate for arachidonate-binding to mammalian 5-, 12- and 15-lipoxygenases, would appear to be true also for linoleate-binding to plant 9- and 13-lipoxygenases.
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Affiliation(s)
- R K Hughes
- John Innes Centre, Norwich Research Park, Norwich, UK.
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21
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O'Donnell VB, Taylor KB, Parthasarathy S, Kühn H, Koesling D, Friebe A, Bloodsworth A, Darley-Usmar VM, Freeman BA. 15-Lipoxygenase catalytically consumes nitric oxide and impairs activation of guanylate cyclase. J Biol Chem 1999; 274:20083-91. [PMID: 10400618 DOI: 10.1074/jbc.274.29.20083] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Analysis of purified soybean and rabbit reticulocyte 15-lipoxygenase (15-LOX) and PA317 cells transfected with human 15-LOX revealed a rapid rate of linoleate-dependent nitric oxide (.NO) uptake that coincided with reversible inhibition of product ((13S)-hydroperoxyoctadecadienoic acid, or (13S)-HPODE) formation. No reaction of .NO (up to 2 microM) with either native (Ered) or ferric LOXs (0.2 microM) metal centers to form nitrosyl complexes occurred at these .NO concentrations. During HPODE-dependent activation of 15-LOX, there was consumption of 2 mol of .NO/mol of 15-LOX. Stopped flow fluorescence spectroscopy showed that.NO (2.2 microM) did not alter the rate or extent of (13S)-HPODE-induced tryptophan fluorescence quenching associated with 15-LOX activation. Additionally, .NO does not inhibit the anaerobic peroxidase activity of 15-LOX, inferring that the inhibitory actions of .NO are due to reaction with the enzyme-bound lipid peroxyl radical, rather than impairment of (13S)-HPODE-dependent enzyme activation. From this, a mechanism of 15-LOX inhibition by .NO is proposed whereby reaction of .NO with EredLOO. generates Ered and LOONO, which hydrolyzes to (13S)-HPODE and nitrite (NO2-). Reactivation of Ered, considerably slower than dioxygenase activity, is then required to complete the catalytic cycle and leads to a net inhibition of rates of (13S)-HPODE formation. This reaction of .NO with 15-LOX inhibited. NO-dependent activation of soluble guanylate cyclase and consequent cGMP production. Since accelerated .NO production, enhanced 15-LOX gene expression, and 15-LOX product formation occurs in diverse inflammatory conditions, these observations indicate that reactions of .NO with lipoxygenase peroxyl radical intermediates will result in modulation of both .NO bioavailability and rates of production of lipid signaling mediators.
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Affiliation(s)
- V B O'Donnell
- Department of Anesthesiology, University of Alabama at Birmingham, Birmingham, Alabama 35233, USA
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Walther M, Holzhütter HG, Kuban RJ, Wiesner R, Rathmann J, Kühn H. The inhibition of mammalian 15-lipoxygenases by the anti-inflammatory drug ebselen: dual-type mechanism involving covalent linkage and alteration of the iron ligand sphere. Mol Pharmacol 1999; 56:196-203. [PMID: 10385701 DOI: 10.1124/mol.56.1.196] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mammalian lipoxygenases have been implicated in inflammation and atherosclerosis and, thus, lipoxygenase inhibitors may be of pharmacological interest. In cells, lipoxygenases occur in a catalytically silent ground state that requires activation to become active. We found that the seleno-organic drug ebselen [2-phenyl-1, 2-benzisoselenazol-3(2H)-one], which exhibits anti-inflammatory properties, irreversibly inhibited pure rabbit 15-lipoxygenase, with an IC50 in the nM range when preincubated with the enzyme in the absence of fatty acid substrates. Subsequent dialysis, gel filtration, or substrate addition did not restore the enzyme activity, and experiments with [14C]ebselen indicated a covalent linkage of the drug. The presence of sulfhydryl compounds in the incubation mixture prevented both enzyme labeling and inactivation, but we did not see any reactivation when sulfhydryl compounds were added afterward. X-ray absorption studies indicated that ebselen did alter the geometry of the iron ligand sphere, and the data are consistent with an iron complexation by the drug. When fatty acid substrate was present during lipoxygenase-ebselen interaction, the inhibitory potency was strongly reduced and a competitive mode of action was observed. These data suggest that ebselen inactivated the catalytically silent ground-state lipoxygenase irreversibly by covalent linkage and alteration of the iron ligand sphere. In contrast, it functions as a competitive inhibitor of the catalytically active enzyme species. The pharmacological relevance of ebselen as a potential in vivo lipoxygenase inhibitor will be discussed.
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Affiliation(s)
- M Walther
- Institute of Biochemistry, University Clinics Charité, Humboldt University, Berlin, Germany
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Kühn H, Borngräber S. Mammalian 15-Lipoxygenases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1999. [DOI: 10.1007/978-1-4615-4861-4_2] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Kühn H, Kuban R, Walther M, Veldink GA. X-ray absorption studies into the iron ligand sphere of plant and animal lipoxygenases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1999; 469:99-104. [PMID: 10667316 DOI: 10.1007/978-1-4615-4793-8_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Affiliation(s)
- H Kühn
- Institute of Biochemistry, University Clinics Charité, Humboldt University, Berlin, Germany
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