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González-Gordo S, López-Jaramillo J, Palma JM, Corpas FJ. Soybean ( Glycine max L.) Lipoxygenase 1 (LOX 1) Is Modulated by Nitric Oxide and Hydrogen Sulfide: An In Vitro Approach. Int J Mol Sci 2023; 24:ijms24098001. [PMID: 37175708 PMCID: PMC10178856 DOI: 10.3390/ijms24098001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 04/03/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023] Open
Abstract
Hydrogen sulfide (H2S) and nitric oxide (NO) are two relevant signal molecules that can affect protein function throughout post-translational modifications (PTMs) such as persulfidation, S-nitrosation, metal-nitrosylation, and nitration. Lipoxygenases (LOXs) are a group of non-heme iron enzymes involved in a wide range of plant physiological functions including seed germination, plant growth and development, and fruit ripening and senescence. Likewise, LOXs are also involved in the mechanisms of response to diverse environmental stresses. Using purified soybean (Glycine max L.) lipoxygenase type 1 (LOX 1) and nitrosocysteine (CysNO) and sodium hydrosulfide (NaHS) as NO and H2S donors, respectively, the present study reveals that both compounds negatively affect LOX activity, suggesting that S-nitrosation and persulfidation are involved. Mass spectrometric analysis of nitrated soybean LOX 1 using a peroxynitrite (ONOO-) donor enabled us to identify that, among the thirty-five tyrosine residues present in this enzyme, only Y214 was exclusively nitrated by ONOO-. The nitration of Y214 seems to affect its interaction with W500, a residue involved in the substrate binding site. The analysis of the structure 3PZW demonstrates the existence of several tunnels that directly communicate the surface of the protein with different internal cysteines, thus making feasible their potential persulfidation, especially C429 and C127. On the other hand, the CysNO molecule, which is hydrophilic and bulkier than H2S, can somehow be accommodated throughout the tunnel until it reaches C127, thus facilitating its nitrosation. Overall, a large number of potential persulfidation targets and the ease by which H2S can reach them through the diffuse tunneling network could be behind their efficient inhibition.
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Affiliation(s)
- Salvador González-Gordo
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Stress, Development and Signaling in Plants, Estación Experimental del Zaidín, Spanish National Research Council (CSIC), Profesor Albareda 1, 18008 Granada, Spain
| | | | - José M Palma
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Stress, Development and Signaling in Plants, Estación Experimental del Zaidín, Spanish National Research Council (CSIC), Profesor Albareda 1, 18008 Granada, Spain
| | - Francisco J Corpas
- Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Stress, Development and Signaling in Plants, Estación Experimental del Zaidín, Spanish National Research Council (CSIC), Profesor Albareda 1, 18008 Granada, Spain
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2
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Structural changes associated with the inactivation of lipoxygenase by pulsed light. Lebensm Wiss Technol 2019. [DOI: 10.1016/j.lwt.2019.108332] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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3
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Srivastava PK, Appu Rao G. AR, Kapoor M. Metal-dependent thermal stability of recombinant endo-mannanase (ManB-1601) belonging to family GH 26 from Bacillus sp. CFR1601. Enzyme Microb Technol 2016; 84:41-9. [DOI: 10.1016/j.enzmictec.2015.12.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/25/2015] [Accepted: 12/17/2015] [Indexed: 10/22/2022]
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4
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Horn T, Ivanov I, Di Venere A, Kakularam KR, Reddanna P, Conrad ML, Richter C, Scheerer P, Kuhn H. Molecular basis for the catalytic inactivity of a naturally occurring near-null variant of human ALOX15. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1702-13. [PMID: 23958500 DOI: 10.1016/j.bbalip.2013.08.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 08/02/2013] [Accepted: 08/06/2013] [Indexed: 11/15/2022]
Abstract
Mammalian lipoxygenases belong to a family of lipid-peroxidizing enzymes, which have been implicated in cardiovascular, hyperproliferative and neurodegenerative diseases. Here we report that a naturally occurring mutation in the hALOX15 gene leads to expression of a catalytically near-null enzyme variant (hGly422Glu). The inactivity may be related to severe misfolding of the enzyme protein, which was concluded from CD-spectra as well as from thermal and chemical stability assays. In silico mutagenesis experiments suggest that most mutations at hGly422 have the potential to induce sterical clash, which might be considered a reason for protein misfolding. hGly422 is conserved among ALOX5, ALOX12 and ALOX15 isoforms and corresponding hALOX12 and hALOX5 mutants also exhibited a reduced catalytic activity. Interestingly, in the hALOX5 Gly429Glu mutants the reaction specificity of arachidonic acid oxygenation was shifted from 5S- to 8S- and 12R-H(p)ETE formation. Taken together, our data indicate that the conserved glycine is of functional importance for these enzyme variants and most mutants at this position lose catalytic activity.
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Key Words
- (5Z,8Z,10E,14Z)-12-hydroperoxyeicosa-5,8,10,14-tetraenoic acid
- (5Z,8Z,11Z,13E)-15-hydroperoxyeicosa-5,8,11,13-tetraenoic acid
- (5Z,9E,11Z,14Z)-8-hydroperoxyicosa-5,9,11,14-tetraenoic acid
- (9Z,11E,13S)-13-hydroperoxyoctadeca-9,11-dienoic acid
- 12-H(p)ETE
- 13-H(p)ODE
- 15-H(p)ETE
- 8-H(p)ETE
- ALOX
- ALOX15
- ALOX15 gene variation
- HETE
- HpETE
- IPTG
- Isopropyl-β-d-thiogalactopyranoside
- LOXs
- Lipid peroxidation
- Lipoxygenase
- Misfolding
- UTR
- arachidonate lipoxygenase
- hydroperoxyeicosatetraenoic acid
- hydroxyeicosatetraenoic acid
- lipoxygenases
- untranslated region
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Affiliation(s)
- Thomas Horn
- Institute of Biochemistry, University Medicine Berlin-Charité, Charitéplatz 1, D-10117 Berlin, Germany.
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5
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Dahiya V, Chaudhuri TK. Functional Intermediate in the Refolding Pathway of a Large and Multidomain Protein Malate Synthase G. Biochemistry 2013; 52:4517-30. [DOI: 10.1021/bi400328a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Vinay Dahiya
- Kusuma School of Biological
Sciences, Indian Institute of Technology Delhi, Hauz Khas, New
Delhi − 110016, India
| | - Tapan K. Chaudhuri
- Kusuma School of Biological
Sciences, Indian Institute of Technology Delhi, Hauz Khas, New
Delhi − 110016, India
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6
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Di Venere A, Horn T, Stehling S, Mei G, Masgrau L, González-Lafont A, Kühn H, Ivanov I. Role of Arg403 for thermostability and catalytic activity of rabbit 12/15-lipoxygenase. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1079-88. [PMID: 23438511 DOI: 10.1016/j.bbalip.2013.02.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 01/10/2013] [Accepted: 02/13/2013] [Indexed: 11/30/2022]
Abstract
12/15-Lipoxygenases (12/15-LOX) have been implicated in inflammatory and hyperproliferative diseases but the numerous aspects of structural biology of these enzymes are far from clear. Early mutagenesis data and structural modeling of enzyme-substrate complexes suggested that Arg403, which is localized at the entrance of the putative substrate binding pocket, might interact with the fatty acid carboxylic group. On the other hand, side-chain of Arg403 is a part of an ionic network with the residues of α2-helix, which undergoes pronounced conformation changes upon inhibitor binding. To explore the role of Arg403 for catalysis in more detail we exchanged positively charged Arg403 to neutral Leu and quantified structural and functional consequences of the alteration at the site of mutation using fluorometric techniques. We found that a loss of electrostatic interaction between Arg403 and negatively charged amino acid residues of α2-helix has only minor impact on protein folding, but partially destabilized the tertiary structure of the enzyme. We hypothesize that interaction of Arg403 with the substrate's carboxylate might be involved in a complex mechanism triggering conformational changes of the α2-helix, which are required for formation of the catalytically competent dimer r12/15-LOX complex at pre-catalytic stages.
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Affiliation(s)
- Almerinda Di Venere
- Department of Experimental Medicine and Surgery, University of Tor Vergata, Rome, Italy
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7
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Equilibrium and kinetics of the unfolding and refolding of Escherichia coli Malate Synthase G monitored by circular dichroism and fluorescence spectroscopy. Biochimie 2010; 92:491-8. [DOI: 10.1016/j.biochi.2010.01.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Accepted: 01/11/2010] [Indexed: 11/20/2022]
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8
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pH Induces Thermal Unfolding of UTI: An Implication of Reversible and Irreversible Mechanism Based on the Analysis of Thermal Stability, Thermodynamic, Conformational Characterization. J Fluoresc 2007; 18:305-17. [DOI: 10.1007/s10895-007-0270-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Accepted: 10/08/2007] [Indexed: 11/26/2022]
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9
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Roopashree S, Singh S, Gowda L, Rao A. Dual-function protein in plant defence: seed lectin from Dolichos biflorus (horse gram) exhibits lipoxygenase activity. Biochem J 2006; 395:629-39. [PMID: 16441240 PMCID: PMC1462680 DOI: 10.1042/bj20051889] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Plant-pathogen interactions play a vital role in developing resistance to pests. Dolichos biflorus (horse gram), a leguminous pulse crop of the subtropics, exhibits amazing defence against attack by pests/pathogens. Investigations to locate the possible source of the indomitable pest resistance of D. biflorus, which is the richest source of LOX (lipoxygenase) activity, have led to a molecule that exhibits LOX-like functions. The LOX-like activity associated with the molecule, identified by its structure and stability to be a tetrameric lectin, was found to be unusual. The evidence for the lectin protein with LOX activity has come from (i) MALDI-TOF (matrix-assisted laser-desorption ionization-time-of-flight) MS, (ii) N-terminal sequencing, (iii) partial sequencing of the tryptic fragments of the protein, (iv) amino acid composition, and (v) the presence of an Mn2+ ion. A hydrophobic binding site of the tetrameric lectin, along with the presence of an Mn2+ ion, accounts for the observed LOX like activity. This is the first ever report of a protein exhibiting both haemagglutination and LOX-like activity. The two activities are associated with separate loci on the same protein. LOX activity associated with this molecule adds a new dimension to our understanding of lectin functions. This observation has wide implications for the understanding of plant defence mechanisms against pests and the cellular complexity in plant-pathogen interactions that may lead to the design of transgenics with potential to impart pest resistance to other crops.
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Affiliation(s)
- Subbaiah Roopashree
- Department of Protein Chemistry and Technology, Central Food Technological Research Institute, Mysore 570020, India
| | - Sridevi Annapurna Singh
- Department of Protein Chemistry and Technology, Central Food Technological Research Institute, Mysore 570020, India
| | - Lalitha R. Gowda
- Department of Protein Chemistry and Technology, Central Food Technological Research Institute, Mysore 570020, India
| | - A. G. Appu Rao
- Department of Protein Chemistry and Technology, Central Food Technological Research Institute, Mysore 570020, India
- To whom correspondence should be addressed (email )
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10
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Osváth S, Jäckel M, Agócs G, Závodszky P, Köhler G, Fidy J. Domain interactions direct misfolding and amyloid formation of yeast phosphoglycerate kinase. Proteins 2006; 62:909-17. [PMID: 16353200 DOI: 10.1002/prot.20823] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
There are proteins that are built of two structural domains and are deposited full-length in amyloid plaques formed in various diseases. In spite of the known differences in the mechanisms of folding of single- and multidomain proteins, no published studies can be found that address the role of the domain-domain interactions during misfolding and amyloid formation. By the discovery of the role of domain-domain interactions, here we provide important insight in the submolecular mechanism of amyloid formation. A model system based on yeast phosphoglycerate kinase was designed. This system includes the wild-type yeast phosphoglycerate kinase and single-tryptophan mutants of the individual N and C terminal domains and the complete protein. Electron microscopic measurements proved that amyloid fibrils grow from all mutants under identical conditions as for the wild-type protein. Misfolding and amyloid formation was followed in stopped-flow and manual mixing experiments on the 1 ms to 4 days timescale. Tryptophan fluorescence was used for selective detection of conformational changes accompanying the formation of the amyloidogenic intermediates and the growth of amyloid fibrils. The interactions between the polypeptide chains of the two domains direct the misfolding process from the early steps to the amyloid formation, and influence the final structure. The kinetics of misfolding is different for the individual domains, pointing to the significance of the amino acid sequence. Misfolding of the domains within the complete protein is synchronized indicating that domain-domain interactions direct the misfolding and amyloid formation mechanism.
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Affiliation(s)
- Szabolcs Osváth
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary.
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11
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Santra MK, Banerjee A, Rahaman O, Panda D. Unfolding pathways of human serum albumin: Evidence for sequential unfolding and folding of its three domains. Int J Biol Macromol 2005; 37:200-4. [PMID: 16324740 DOI: 10.1016/j.ijbiomac.2005.10.009] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2005] [Revised: 10/26/2005] [Accepted: 10/26/2005] [Indexed: 11/19/2022]
Abstract
Human serum albumin (HSA) contains three alpha-helical domains (I-III). The unfolding process of these domains was monitored using covalently bound fluorescence probes; domain I was monitored by N-(1-pyrene)maleimide (PM) conjugated with cys-34, domain II was monitored by the lone tryptophan residue and domain III was followed by p-nitrophenyl anthranilate (NPA) conjugated with Tyrosine-411 (Tyr-411). Using domain-specific probes, we found that guanidium hydrochloride-induced unfolding of HSA occurred sequentially. The unfolding of domain II preceded that of domain I and the unfolding of domain III followed that of domain I. In addition, the domains I and III refolded within the dead time of the fluorescence recovery experiment while the refolding of domain II occurred slowly. The results suggest that individual domain of a multi-domain protein can fold and unfold sequentially.
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Affiliation(s)
- Manas Kumar Santra
- School of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India.
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12
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Ignatova Z, Wischnewski F, Notbohm H, Kasche V. Pro-sequence and Ca2+-binding: Implications for Folding and Maturation of Ntn-hydrolase Penicillin Amidase from E.coli. J Mol Biol 2005; 348:999-1014. [PMID: 15843029 DOI: 10.1016/j.jmb.2005.03.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2004] [Revised: 03/01/2005] [Accepted: 03/02/2005] [Indexed: 11/26/2022]
Abstract
Penicillin amidase (PA) is a bacterial periplasmic enzyme synthesized as a pre-pro-PA precursor. The pre-sequence mediates membrane translocation. The intramolecular pro-sequence is expressed along with the A and B chains but is rapidly removed in an autocatalytic manner. In extensive studies we show here that the pro-peptide is required for the correct folding of PA. Pro-PA and PA unfold via a biphasic transition that is more pronounced in the case of PA. According to size-exclusion chromatography and limited proteolysis experiments, the inflection observed in the equilibrium unfolding curves corresponds to an intermediate in which the N-terminal domain (A-chain) still possesses native-like topology, whereas the B-chain is unfolded to a large extent. In a series of in vitro experiments with a slow processing mutant pro-PA, we show that the pro-sequence in cis functions as a folding catalyst and accelerates the folding rate by seven orders of magnitude. In the absence of the pro-domain the PA refolds to a stable inactive molten globule intermediate that has native-like secondary but little tertiary structure. The pro-sequence of the homologous Alcaligenes faecalis PA can facilitate the folding of the hydrolase domain of Escherichia coli PA when added in trans (as a separate polypeptide chain). The isolated pro-sequence has a random structure in solution. However, difference circular dichroism spectra of native PA and native PA with pro-peptide added in trans suggest that the pro-sequence adopts an alpha-helical conformation in the context of the mature PA molecule. Furthermore, our results establish that Ca2+, found in the crystal structure, is not directly involved in the folding process. The cation shifts the equilibrium towards the native state and facilitates the autocatalytic processing of the pro-peptide.
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Affiliation(s)
- Zoya Ignatova
- Institute of Biotechnology II, Technical University Hamburg-Harburg, Denickestr. 15, 21073 Hamburg, Germany.
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13
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Di Venere A, Salucci ML, van Zadelhoff G, Veldink G, Mei G, Rosato N, Finazzi-Agrò A, Maccarrone M. Structure-to-function relationship of mini-lipoxygenase, a 60-kDa fragment of soybean lipoxygenase-1 with lower stability but higher enzymatic activity. J Biol Chem 2003; 278:18281-8. [PMID: 12626522 DOI: 10.1074/jbc.m212122200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Lipoxygenase-1 (Lox-1) is a member of the lipoxygenase family, a class of dioxygenases that take part in the metabolism of polyunsatured fatty acids in eukaryotes. Tryptic digestion of soybean Lox-1 is known to produce a 60 kDa fragment, termed "mini-Lox," which shows enhanced catalytic efficiency and higher membrane-binding ability than the native enzyme (Maccarrone, M., Salucci, M. L., van Zadelhoff, G., Malatesta, F., Veldink, G. Vliegenthart, J. F. G., and Finazzi-Agrò, A. (2001) Biochemistry 40, 6819-6827). In this study, we have investigated the stability of mini-Lox in guanidinium hydrochloride and under high pressure by fluorescence and circular dichroism spectroscopy. Only a partial unfolding could be obtained at high pressure in the range 1-3000 bar at variance with guanidinium hydrochloride. However, in both cases a reversible denaturation was observed. The denaturation experiments demonstrate that mini-Lox is a rather unstable molecule, which undergoes a two-step unfolding transition at moderately low guanidinium hydrochloride concentration (0-4.5 m). Both chemical- and physical-induced denaturation suggest that mini-Lox is more hydrated than Lox-1, an observation also confirmed by 1-anilino-8-naphthalenesulfonate (ANS) binding studies. We have also investigated the occurrence of substrate-induced changes in the protein tertiary structure by dynamic fluorescence techniques. In particular, eicosatetraynoic acid, an irreversible inhibitor of lipoxygenase, has been used to mimic the effect of substrate binding. We demonstrated that mini-Lox is indeed characterized by much larger conformational changes than those occurring in the native Lox-1 upon binding of eicosatetraynoic acid. Finally, by both activity and fluorescence measurements we have found that 1-anilino-8-naphthalenesulfonate has access to the active site of mini-Lox but not to that of intact Lox-1. These findings strongly support the hypothesis that the larger hydration of mini-Lox renders this molecule more flexible, and therefore less stable.
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Maccarrone M, Battista N, Bari M, Finazzi-Agrò A. Lipoxygenase activity in altered gravity. ADVANCES IN SPACE BIOLOGY AND MEDICINE 2002; 8:1-17. [PMID: 12951691 DOI: 10.1016/s1569-2574(02)08013-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Lipoxygenases are a family of enzymes which dioxygenate unsaturated fatty acids, thus initiating lipoperoxidation of membranes or the synthesis of signalling molecules, or inducing structural and metabolic changes in the cell. This activity is the basis for the critical role of lipoxygenases in a number of pathophysiological conditions, both in animals and plants. We review the effects of microgravity on the catalytic efficiency of purified soybean (Glycine max) lipoxygenase-1, as well as the modulation of the activity and expression of 5-lipoxygenase in human erythroleukemia K562 cells subjected to altered gravity. We also outline the molecular properties of the lipoxygenase family and discuss its possible involvement in space-related processes, such as apoptosis (programmed cell death) and immuno-depression. Finally, we discuss the modulation of cyclooxygenase activity and expression in K562 cells exposed to altered gravity, because cyclooxygenase catalyzes the oxidation of arachidonate through a pathway different from that catalyzed by lipoxygenase activity.
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Affiliation(s)
- Mauro Maccarrone
- Department of Experimental Medicine and Biochemical Sciences and Biomedical Space Center, University of Rome Tor Vergata, Rome, Italy
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15
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Malvezzi-Campeggi F, Rosato N, Finazzi-Agrò A, Maccarrone M. Effect of denaturants on the structural properties of soybean lipoxygenase-1. Biochem Biophys Res Commun 2001; 289:1295-300. [PMID: 11741336 DOI: 10.1006/bbrc.2001.6109] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect of chemical (urea) and physical (temperature and high pressure) denaturation on the structural properties of soybean lipoxygenase-1 (LOX1) was analyzed through dynamic fluorescence spectroscopy and circular dichroism. We show that the fluorescence decay of the native protein could be fitted by two lorentzian distributions of lifetimes, centered at 1 and 4 ns. The analysis of the urea-denatured protein suggested that the shorter distribution is mostly due to the tryptophan residues located in the N-terminal domain of LOX1. We also show that a pressure of 2400 bar and a temperature of 55 degrees C brought LOX-1 to a state similar to a recently described stable intermediate "I." Analysis of circular dichroism spectra indicated a substantial decrease of alpha-helix compared with beta-structure under denaturing conditions, suggesting a higher stability of the N-terminal compared with the C-terminal domain in the denaturation process.
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16
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Maccarrone M, Melino G, Finazzi-Agrò A. Lipoxygenases and their involvement in programmed cell death. Cell Death Differ 2001; 8:776-84. [PMID: 11526430 DOI: 10.1038/sj.cdd.4400908] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2001] [Revised: 05/09/2001] [Accepted: 05/10/2001] [Indexed: 01/31/2023] Open
Abstract
Lipoxygenases are a family of enzymes which dioxygenate unsaturated fatty acids, thus initiating lipoperoxidation of membranes and the synthesis of signaling molecules. Consequently, they induce structural and metabolic changes in the cell in a number of pathophysiological conditions. Recently, a pro-apoptotic effect of lipoxygenase, and of the hydroperoxides produced thereof, has been reported in different cells and tissues, leading to cell death. Anti-apoptotic effects of lipoxygenases have also been reported; however, this has often been based on the use of enzyme inhibitors. Here we review the characteristics of the lipoxygenase family and its involvement in the initiation of oxidative stress-induced apoptosis. Finally, we discuss the role of lipoxygenase activation in apoptosis of animal and plant cells, suggesting a common signal transduction pathway in cell death conserved through evolution of both kingdoms.
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Affiliation(s)
- M Maccarrone
- Department of Experimental Medicine and Biochemical Sciences, University of Rome Tor Vergata, Via di Tor Vergata 135, I-00133 Rome, Italy.
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17
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Maccarrone M, Salucci ML, van Zadelhoff G, Malatesta F, Veldink G, Vliegenthart JF, Finazzi-Agrò A. Tryptic digestion of soybean lipoxygenase-1 generates a 60 kDa fragment with improved activity and membrane binding ability. Biochemistry 2001; 40:6819-27. [PMID: 11389595 DOI: 10.1021/bi010187m] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Lipoxygenases are key enzymes in the metabolism of unsaturated fatty acids. Soybean lipoxygenase-1 (LOX-1), a paradigm for lipoxygenases isolated from different sources, is composed of two domains: a approximately 30 kDa N-terminal domain and a approximately 60 kDa C-terminal domain. We used limited proteolysis and gel-filtration chromatography to generate and isolate a approximately 60 kDa fragment of LOX-1 ("mini-LOX"), produced by trypsin cleavage between lysine 277 and serine 278. Mini-LOX was subjected to N-terminal sequencing and to electrophoretic, chromatographic, and spectroscopic analysis. Mini-LOX was found to be more acidic and more hydrophobic than LOX-1, and with a higher content of alpha-helix. Kinetic analysis showed that mini-LOX dioxygenates linoleic acid with a catalytic efficiency approximately 3-fold higher than that of LOX-1 (33.3 x 10(6) and 10.9 x 10(6) M(-1) x s(-1), respectively), the activation energy of the reaction being 4.5 +/- 0.5 and 8.3 +/- 0.9 kJ x mol(-1) for mini-LOX and LOX-1, respectively. Substrate preference, tested with linoleic, alpha-linolenic, and arachidonic acids, and with linoleate methyl ester, was the same for LOX-1 and mini-LOX, and also identical was the regio- and stereospecificity of the products generated thereof, analyzed by reversed-phase and chiral high-performance liquid chromatography, and by gas chromatography/mass spectrometry. Mini-LOX was able to bind artificial vesicles with higher affinity than LOX-1, but the binding was less affected by calcium ions than was that of LOX-1. Taken together, these results suggest that the N-terminal domain of soybean lipoxygenase-1 might be a built-in inhibitor of catalytic activity and membrane binding ability of the enzyme, with a possible role in physio(patho)logical conditions.
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Affiliation(s)
- M Maccarrone
- Department of Experimental Medicine and Biochemical Sciences, University of Rome, Tor Vergata, Rome, Italy.
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18
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Maccarrone M, Bari M, Battista N, Finazzi-Agrò A. The catalytic efficiency of soybean lipoxygenase-1 is enhanced at low gravity. Biophys Chem 2001; 90:303-6. [PMID: 11407646 DOI: 10.1016/s0301-4622(01)00161-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Maccarrone M, Bari M, Battista N, Finazzi-Agrò A. The catalytic efficiency of soybean lipoxygenase-1 is enhanced at low gravity. Biophys Chem 2001; 90:97-101. [PMID: 11321679 DOI: 10.1016/s0301-4622(01)00132-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Several cellular processes are modified when cells are placed under conditions of weightlessness. As yet, there is no coherent explanation for these observations, nor it is known which biomolecules might act as gravity sensors. Lipoxygenases generate leukotrienes and lipoxins from arachidonic acid, being responsible for many pharmacological and immunological effects, some of which are known to be affected by microgravity. In the course of the 28th parabolic flight campaign of the European Space Agency we measured the activity of pure soybean lipoxygenase-1 on linoleic acid, by a fibre optics spectrometer developed on purpose. It was found that microgravity reduced the apparent Michaelis-Menten constant (Km) of the enzymatic reaction to one fourth with respect to the 1 g control, whereas, the catalytic constant (k(cat)) was unaffected. Consequently, the catalytic efficiency of lipoxygenase-1 (k(cat)/Km) was approximately four-fold higher in flight than on ground. This unprecedented finding suggests that lipoxygenase-1 might be a molecular target for gravity.
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Affiliation(s)
- M Maccarrone
- Department of Experimental Medicine and Biochemical Sciences, University of Rome Tor Vergata, Italy
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Sudharshan E, Srinivasulu S, Appu Rao AG. pH-induced domain interaction and conformational transitions of lipoxygenase-1. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1480:13-22. [PMID: 11004552 DOI: 10.1016/s0167-4838(00)00099-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The multidomain structure of soybean LOX1 was examined over the pH range 1-12. Lipoxygenase-1 activity was reversible over broad pH range of 4-10 due to the reversibility of conformational states of the molecule. Below pH 4.0, due to collapse in hydrophobic interactions, the enzyme unfolded to an irreversible conformation with the properties of molten globule state with a mid point of transition at pH 2.4. This intermediate state lost iron irreversibly. In alkaline pH at 11.5, LOX1 underwent partial unfolding with the exposure of cysteine residues with subsequent oxidation of a pair of cysteine residues in the C-terminal domain and this intermediate showed some properties of molten globule state and retained 35% of activity. Beyond pH 12.0, the enzyme was completely inactivated irreversibly due to irreversible conformational changes. The pH-dependent urea-induced unfolding of LOX1 suggested that LOX1 was more stable at pH 7.0 and least stable at pH 9.0. Furthermore, the urea-induced unfolding of LOX1 indicated that the unfolding was biphasic due to pH-dependent domain interactions and involved sequential unfolding of domains. The loss of enzyme activity at pH 4. 0 and 7.0 occurred much earlier to unfolding of the C-domain at all pHs studied. The combination of urea-induced unfolding measurements and limited proteolysis experiments suggested that at pH 4.0, the domains in LOX1 were less interactive and existed as tightly folded units. Furthermore, these results confirmed the contribution of ionic interactions in the interdomain contacts.
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Affiliation(s)
- E Sudharshan
- Department of Protein Chemistry and Technology, Central Food Technological Research Institute, 570 013, Mysore, India
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