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Martinez Grundman JE, Schultz TD, Schlessman JL, Liu K, Johnson EA, Lecomte JTJ. Heme d formation in a Shewanella benthica hemoglobin. J Inorg Biochem 2024; 259:112654. [PMID: 38959524 DOI: 10.1016/j.jinorgbio.2024.112654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 06/25/2024] [Accepted: 06/25/2024] [Indexed: 07/05/2024]
Abstract
In our continued investigations of microbial globins, we solved the structure of a truncated hemoglobin from Shewanella benthica, an obligate psychropiezophilic bacterium. The distal side of the heme active site is lined mostly with hydrophobic residues, with the exception of a tyrosine, Tyr34 (CD1) and a histidine, His24 (B13). We found that purified SbHbN, when crystallized in the ferric form with polyethylene glycol as precipitant, turned into a green color over weeks. The electron density obtained from the green crystals accommodated a trans heme d, a chlorin-type derivative featuring a γ-spirolactone and a vicinal hydroxyl group on a pyrroline ring. In solution, exposure of the protein to one equivalent of hydrogen peroxide resulted in a similar green color change, but caused by the formation of multiple products. These were oxidation species released on protein denaturation, likely including heme d, and a species with heme covalently attached to the polypeptide. The Tyr34Phe replacement prevented the formation of both heme d and the covalent linkage. The ready modification of heme b by SbHbN expands the range of chemistries supported by the globin fold and offers a route to a novel heme cofactor.
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Affiliation(s)
| | - Thomas D Schultz
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | | | - Kevin Liu
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Eric A Johnson
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Juliette T J Lecomte
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA.
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2
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Beale AD, Hayter EA, Crosby P, Valekunja UK, Edgar RS, Chesham JE, Maywood ES, Labeed FH, Reddy AB, Wright KP, Lilley KS, Bechtold DA, Hastings MH, O'Neill JS. Mechanisms and physiological function of daily haemoglobin oxidation rhythms in red blood cells. EMBO J 2023; 42:e114164. [PMID: 37554073 PMCID: PMC10548169 DOI: 10.15252/embj.2023114164] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/16/2023] [Accepted: 07/16/2023] [Indexed: 08/10/2023] Open
Abstract
Cellular circadian rhythms confer temporal organisation upon physiology that is fundamental to human health. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body, but their physiological function is poorly understood. Here, we present a novel biochemical assay for haemoglobin (Hb) oxidation status which relies on a redox-sensitive covalent haem-Hb linkage that forms during SDS-mediated cell lysis. Formation of this linkage is lowest when ferrous Hb is oxidised, in the form of ferric metHb. Daily haemoglobin oxidation rhythms are observed in mouse and human RBCs cultured in vitro, or taken from humans in vivo, and are unaffected by mutations that affect circadian rhythms in nucleated cells. These rhythms correlate with daily rhythms in core body temperature, with temperature lowest when metHb levels are highest. Raising metHb levels with dietary sodium nitrite can further decrease daytime core body temperature in mice via nitric oxide (NO) signalling. These results extend our molecular understanding of RBC circadian rhythms and suggest they contribute to the regulation of body temperature.
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Affiliation(s)
| | - Edward A Hayter
- Centre for Biological Timing, Faculty of Biology, Medicine and HealthUniversity of ManchesterManchesterUK
| | - Priya Crosby
- MRC Laboratory of Molecular BiologyCambridgeUK
- Present address:
Department of Chemistry and BiochemistryUniversity of California, Santa CruzSanta CruzCAUSA
| | - Utham K Valekunja
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA
- Institute for Translational Medicine and Therapeutics, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA
| | - Rachel S Edgar
- Department of Infectious DiseasesImperial College LondonLondonUK
| | | | | | - Fatima H Labeed
- Faculty of Engineering and Physical SciencesUniversity of SurreyGuildfordUK
| | - Akhilesh B Reddy
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA
- Institute for Translational Medicine and Therapeutics, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA
| | - Kenneth P Wright
- Department of Integrative Physiology, Sleep and Chronobiology LaboratoryUniversity of Colorado BoulderBoulderCOUSA
| | - Kathryn S Lilley
- Cambridge Centre for Proteomics, Department of BiochemistryUniversity of CambridgeCambridgeUK
| | - David A Bechtold
- Centre for Biological Timing, Faculty of Biology, Medicine and HealthUniversity of ManchesterManchesterUK
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3
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Hill K, Bailey BG, Mouton MB, Williamson HR. Hidden Complexity in the Mechanism of the Autoreduction of Myoglobin Compound II. ACS OMEGA 2022; 7:22906-22914. [PMID: 35811930 PMCID: PMC9260896 DOI: 10.1021/acsomega.2c02798] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 06/06/2022] [Indexed: 06/15/2023]
Abstract
The non-native oxidation of horse heart myoglobin with hydrogen peroxide produces compound II which autoreduces by utilizing an internal oxidation site. Here, we utilize full UV-visible time-dependent kinetics with global kinetic singular value decomposition analysis to explore the mechanism and uncover more detail about the high-valent heme spectral features. By varying the hydrogen peroxide and myoglobin concentration, we were able to uncover more detailed spectra of myoglobin compound II and the autoreduction rate under several different pH conditions. The compound II spectra demonstrate pH-dependent features with an inflection point around pH 5.7 ± 0.1. The rate of autoreduction of compound II, k 2, increases with lower pH with a half-power proton dependence and no indication of a pK a > 3.9 ± 0.2, indicating that the autoreduction is still dependent on the protonation of the ferryl oxo species. The k 2 also demonstrates both hydrogen peroxide and myoglobin dependency. At myoglobin concentrations greater than 6.6 μM, the k 2 is myoglobin-independent, but for lower concentrations, a pH-sensitive concentration dependence is seen.
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Affiliation(s)
| | - Breanna G. Bailey
- Department of Chemistry, Xavier
University of Louisiana, 1 Drexel Dr., New Orleans, Louisiana 70125, United States
| | - Meghan B. Mouton
- Department of Chemistry, Xavier
University of Louisiana, 1 Drexel Dr., New Orleans, Louisiana 70125, United States
| | - Heather R. Williamson
- Department of Chemistry, Xavier
University of Louisiana, 1 Drexel Dr., New Orleans, Louisiana 70125, United States
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4
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Hofbauer S, Pignataro M, Borsari M, Bortolotti CA, Di Rocco G, Ravenscroft G, Furtmüller PG, Obinger C, Sola M, Battistuzzi G. Pseudoperoxidase activity, conformational stability, and aggregation propensity of the His98Tyr myoglobin variant: implications for the onset of myoglobinopathy. FEBS J 2021; 289:1105-1117. [PMID: 34679218 PMCID: PMC9298411 DOI: 10.1111/febs.16235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/09/2021] [Accepted: 10/18/2021] [Indexed: 01/17/2023]
Abstract
The autosomal dominant striated muscle disease myoglobinopathy is due to the single point mutation His98Tyr in human myoglobin (MB), the heme protein responsible for binding, storage, and controlled release of O2 in striated muscle. In order to understand the molecular basis of this disease, a comprehensive biochemical and biophysical study on wt MB and the variant H98Y has been performed. Although only small differences exist between the active site architectures of the two proteins, the mutant (a) exhibits an increased reactivity toward hydrogen peroxide, (b) exhibits a higher tendency to form high‐molecular‐weight aggregates, and (c) is more prone to heme bleaching, possibly as a consequence of the observed H2O2‐induced formation of the Tyr98 radical close to the metal center. These effects add to the impaired oxygen binding capacity and faster heme dissociation of the H98Y variant compared with wt MB. As the above effects result from bond formation/cleavage events occurring at the distal and proximal heme sites, it appears that the molecular determinants of the disease are localized there. These findings set the basis for clarifying the onset of the cascade of chemical events that are responsible for the pathological symptoms of myoglobinopathy.
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Affiliation(s)
- Stefan Hofbauer
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Marcello Pignataro
- Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Italy
| | - Marco Borsari
- Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Italy
| | | | - Giulia Di Rocco
- Department of Life Sciences, University of Modena and Reggio Emilia, Italy
| | - Gianina Ravenscroft
- Harry Perkins Institute of Medical Research, Nedlands, WA, Australia.,School of Biomedical Sciences, University of Western Australia, Nedlands, WA, Australia
| | - Paul G Furtmüller
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Christian Obinger
- Department of Chemistry, Institute of Biochemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Marco Sola
- Department of Life Sciences, University of Modena and Reggio Emilia, Italy
| | - Gianantonio Battistuzzi
- Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Italy
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5
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Parsons BJ. Kinetic simulations of the effect of antioxidants on the metmyoglobin reactions with hydrogen peroxide and their relevance and application to the Trolox equivalent equivalent antioxidant assay. INT J CHEM KINET 2021. [DOI: 10.1002/kin.21500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Barry J. Parsons
- School of Clinical and Applied Sciences Leeds Beckett University Leeds UK
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6
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Shumayrikh NM, Warren JJ, Bennet AJ, Sen D. A heme•DNAzyme activated by hydrogen peroxide catalytically oxidizes thioethers by direct oxygen atom transfer rather than by a Compound I-like intermediate. Nucleic Acids Res 2021; 49:1803-1815. [PMID: 33476369 PMCID: PMC7913675 DOI: 10.1093/nar/gkab007] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 12/21/2022] Open
Abstract
Hemin [Fe(III)-protoporphyrin IX] is known to bind tightly to single-stranded DNA and RNA molecules that fold into G-quadruplexes (GQ). Such complexes are strongly activated for oxidative catalysis. These heme•DNAzymes and ribozymes have found broad utility in bioanalytical and medicinal chemistry and have also been shown to occur within living cells. However, how a GQ is able to activate hemin is poorly understood. Herein, we report fast kinetic measurements (using stopped-flow UV-vis spectrophotometry) to identify the H2O2-generated activated heme species within a heme•DNAzyme that is active for the oxidation of a thioether substrate, dibenzothiophene (DBT). Singular value decomposition and global fitting analysis was used to analyze the kinetic data, with the results being consistent with the heme•DNAzyme's DBT oxidation being catalyzed by the initial Fe(III)heme-H2O2 complex. Such a complex has been predicted computationally to be a powerful oxidant for thioether substrates. In the heme•DNAzyme, the DNA GQ enhances both the kinetics of formation of the active intermediate as well as the oxidation step of DBT by the active intermediate. We show, using both stopped flow spectrophotometry and EPR measurements, that a classic Compound I is not observable during the catalytic cycle for thioether sulfoxidation.
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Affiliation(s)
- Nisreen M Shumayrikh
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Jeffrey J Warren
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Andrew J Bennet
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Dipankar Sen
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
- Department of Molecular Biology & Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
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7
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Reversible Oxidative Modifications in Myoglobin and Functional Implications. Antioxidants (Basel) 2020; 9:antiox9060549. [PMID: 32599765 PMCID: PMC7346209 DOI: 10.3390/antiox9060549] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/14/2020] [Accepted: 06/18/2020] [Indexed: 12/22/2022] Open
Abstract
Myoglobin (Mb), an oxygen-binding heme protein highly expressed in heart and skeletal muscle, has been shown to undergo oxidative modifications on both an inter- and intramolecular level when exposed to hydrogen peroxide (H2O2) in vitro. Here, we show that exposure to H2O2 increases the peroxidase activity of Mb. Reaction of Mb with H2O2 causes covalent binding of heme to the Mb protein (Mb-X), corresponding to an increase in peroxidase activity when ascorbic acid is the reducing co-substrate. Treatment of H2O2-reacted Mb with ascorbic acid reverses the Mb-X crosslink. Reaction with H2O2 causes Mb to form dimers, trimers, and larger molecular weight Mb aggregates, and treatment with ascorbic acid regenerates Mb monomers. Reaction of Mb with H2O2 causes formation of dityrosine crosslinks, though the labile nature of the crosslinks broken by treatment with ascorbic acid suggests that the reversible aggregation of Mb is mediated by crosslinks other than dityrosine. Disappearance of a peptide containing a tryptophan residue when Mb is treated with H2O2 and the peptide’s reappearance after subsequent treatment with ascorbic acid suggest that tryptophan side chains might participate in the labile crosslinking. Taken together, these data suggest that while exposure to H2O2 causes Mb-X formation, increases Mb peroxidase activity, and causes Mb aggregation, these oxidative modifications are reversible by treatment with ascorbic acid. A caveat is that future studies should demonstrate that these and other in vitro findings regarding properties of Mb have relevance in the intracellular milieu, especially in regard to actual concentrations of metMb, H2O2, and ascorbate that would be found in vivo.
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8
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Pires IS, Belcher DA, Hickey R, Miller C, Badu‐Tawiah AK, Baek JH, Buehler PW, Palmer AF. Novel manufacturing method for producing apohemoglobin and its biophysical properties. Biotechnol Bioeng 2019; 117:125-145. [DOI: 10.1002/bit.27193] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 06/08/2019] [Accepted: 10/11/2019] [Indexed: 12/25/2022]
Affiliation(s)
- Ivan S. Pires
- William G. Lowrie Department of Chemical and Biomolecular EngineeringThe Ohio State University Columbus Ohio
| | - Donald A. Belcher
- William G. Lowrie Department of Chemical and Biomolecular EngineeringThe Ohio State University Columbus Ohio
| | - Richard Hickey
- William G. Lowrie Department of Chemical and Biomolecular EngineeringThe Ohio State University Columbus Ohio
| | - Colbert Miller
- Department of Chemistry and BiochemistryThe Ohio State University Columbus Ohio
| | | | - Jin Hyen Baek
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and ResearchFood and Drug Administration Silver Spring Maryland
| | - Paul W. Buehler
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and ResearchFood and Drug Administration Silver Spring Maryland
| | - Andre F. Palmer
- William G. Lowrie Department of Chemical and Biomolecular EngineeringThe Ohio State University Columbus Ohio
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Catalase-Like Antioxidant Activity is Unaltered in Hypochlorous Acid Oxidized Horse Heart Myoglobin. Antioxidants (Basel) 2019; 8:antiox8090414. [PMID: 31540488 PMCID: PMC6770884 DOI: 10.3390/antiox8090414] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/27/2019] [Accepted: 09/16/2019] [Indexed: 01/01/2023] Open
Abstract
Activated neutrophils release myeloperoxidase that produces the potent oxidant hypochlorous acid (HOCl). Exposure of the oxygen transport protein horse heart myoglobin (hhMb) to HOCl inhibits Iron III (Fe(III))-heme reduction by cytochrome b5 to oxygen-binding Iron II (Fe(II))Mb. Pathological concentrations of HOCl yielded myoglobin oxidation products of increased electrophoretic mobility and markedly different UV/Vis absorbance. Mass analysis indicated HOCl caused successive mass increases of 16 a.m.u., consistent serial addition of molecular oxygen to the protein. By contrast, parallel analysis of protein chlorination by quantitative mass spectrometry revealed a comparatively minor increase in the 3-chlorotyrosine/tyrosine ratio. Pre-treatment of hhMb with HOCl affected the peroxidase reaction between the hemoprotein and H2O2 as judged by a HOCl dose-dependent decrease in spin-trapped tyrosyl radical detected by electron paramagnetic resonance (EPR) spectroscopy and the rate constant of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) oxidation. By contrast, Mb catalase-like antioxidant activity remained unchanged under the same conditions. Notably, HOCl-modification of Mb decreased the rate of ferric-to-ferrous Mb reduction by a cytochrome b5 reductase system. Taken together, these data indicate oxidizing HOCl promotes Mb oxidation but not chlorination and that oxidized Mb shows altered Mb peroxidase-like activity and diminished rates of one-electron reduction by cytochrome b5 reductase, possibly affecting oxygen storage and transport however, Mb-catalase-like antioxidant activity remains unchanged.
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10
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Pott M, Hayashi T, Mori T, Mittl PRE, Green AP, Hilvert D. A Noncanonical Proximal Heme Ligand Affords an Efficient Peroxidase in a Globin Fold. J Am Chem Soc 2018; 140:1535-1543. [DOI: 10.1021/jacs.7b12621] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Moritz Pott
- Laboratory of Organic Chemistry, ETH Zurich, Zurich 8093, Switzerland
| | - Takahiro Hayashi
- Laboratory of Organic Chemistry, ETH Zurich, Zurich 8093, Switzerland
| | - Takahiro Mori
- Laboratory of Organic Chemistry, ETH Zurich, Zurich 8093, Switzerland
| | - Peer R. E. Mittl
- Department of Biochemistry, University of Zurich, Zurich 8057, Switzerland
| | - Anthony P. Green
- School of Chemistry & Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Donald Hilvert
- Laboratory of Organic Chemistry, ETH Zurich, Zurich 8093, Switzerland
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11
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Ma D, Kim YHB, Cooper B, Oh JH, Chun H, Choe JH, Schoonmaker JP, Ajuwon K, Min B. Metabolomics Profiling to Determine the Effect of Postmortem Aging on Color and Lipid Oxidative Stabilities of Different Bovine Muscles. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:6708-6716. [PMID: 28700223 DOI: 10.1021/acs.jafc.7b02175] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The objective of this study was to identify metabolites that could be associated with oxidative stability of aged bovine muscles. Three muscles (longissimus lumbrum (LL), semimembranosus (SM), and psoas major (PM)) from seven beef carcasses at 1 day postmortem were divided into three sections and assigned to three aging periods (9, 16, and 23 days). Although an increase in discoloration was found in all muscles with aging, LL was the most color/lipid oxidative stable, followed by SM and PM (P < 0.05). Lower myoglobin and nonheme iron contents were observed in LL compared to those in SM and PM (P < 0.05). The HPLC-ESI-MS-based metabolomics analysis identified metabolites that were significantly responsive to aging and/or muscle type, such as acyl carnitines, free amino acids, nucleotides, nucleosides, and glucuronides. The results from the current study suggest that color and oxidative stability could be associated with aging but are also muscle-specific. Further studies determining the exact role of the identified metabolites in the color and oxidative stability of beef muscles are warranted.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Byungrok Min
- Food Science and Technology Program, University of Maryland Eastern Shore , Princess Anne, Maryland 21853, United States
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12
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Reeder BJ. Redox and Peroxidase Activities of the Hemoglobin Superfamily: Relevance to Health and Disease. Antioxid Redox Signal 2017; 26:763-776. [PMID: 27637274 DOI: 10.1089/ars.2016.6803] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
SIGNIFICANCE Erythrocyte hemoglobin (Hb) and myocyte myoglobin, although primarily oxygen-carrying proteins, have the capacity to do redox chemistry. Such redox activity in the wider family of globins now appears to have important associations with the mechanisms of cell stress response. In turn, an understanding of such mechanisms in vivo may have a potential in the understanding of cancer therapy resistance and neurodegenerative disorders such as Alzheimer's. Recent Advances: There has been an enhanced understanding of the redox chemistry of the globin superfamily in recent years, leading to advances in development of Hb-based blood substitutes and in hypotheses relating to specific disease mechanisms. Neuroglobin (Ngb) and cytoglobin (Cygb) have been linked to cell protection mechanisms against hypoxia and oxidative stress, with implications in the onset and progression of neurodegenerative diseases for Ngb and cancer for Cygb. CRITICAL ISSUES Despite advances in the understanding of redox chemistry of globins, the physiological roles of many of these proteins still remain ambiguous at best. Confusion over potential physiological roles may relate to multifunctional roles for globins, which may be modulated by surface-exposed cysteine pairs in some globins. Such roles may be critical in deciphering the relationships of these globins in human diseases. FUTURE DIRECTIONS Further studies are required to connect the considerable knowledge on the mechanisms of globin redox chemistry in vitro with the physiological and pathological roles of globins in vivo. In doing so, new therapies for neurodegenerative disorders and cancer therapy resistance may be targeted. Antioxid. Redox Signal. 26, 763-776.
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Affiliation(s)
- Brandon J Reeder
- School of Biological Sciences, University of Essex , Essex, United Kingdom
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13
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Release of free amino acids upon oxidation of peptides and proteins by hydroxyl radicals. Anal Bioanal Chem 2017; 409:2411-2420. [PMID: 28108753 PMCID: PMC5352754 DOI: 10.1007/s00216-017-0188-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/20/2016] [Accepted: 01/03/2017] [Indexed: 12/11/2022]
Abstract
Hydroxyl radical-induced oxidation of proteins and peptides can lead to the cleavage of the peptide, leading to a release of fragments. Here, we used high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) and pre-column online ortho-phthalaldehyde (OPA) derivatization-based amino acid analysis by HPLC with diode array detection and fluorescence detection to identify and quantify free amino acids released upon oxidation of proteins and peptides by hydroxyl radicals. Bovine serum albumin (BSA), ovalbumin (OVA) as model proteins, and synthetic tripeptides (comprised of varying compositions of the amino acids Gly, Ala, Ser, and Met) were used for reactions with hydroxyl radicals, which were generated by the Fenton reaction of iron ions and hydrogen peroxide. The molar yields of free glycine, aspartic acid, asparagine, and alanine per peptide or protein varied between 4 and 55%. For protein oxidation reactions, the molar yields of Gly (∼32-55% for BSA, ∼10-21% for OVA) were substantially higher than those for the other identified amino acids (∼5-12% for BSA, ∼4-6% for OVA). Upon oxidation of tripeptides with Gly in C-terminal, mid-chain, or N-terminal positions, Gly was preferentially released when it was located at the C-terminal site. Overall, we observe evidence for a site-selective formation of free amino acids in the OH radical-induced oxidation of peptides and proteins, which may be due to a reaction pathway involving nitrogen-centered radicals.
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Chikezie PC, Ekechukwu CU. Acute patho-toxicological indicators of methaemoglobinemia. JOURNAL OF ACUTE DISEASE 2016. [DOI: 10.1016/j.joad.2016.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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15
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Samuni U, Czapski G, Goldstein S. Nitroxide radicals as research tools: Elucidating the kinetics and mechanisms of catalase-like and "suicide inactivation" of metmyoglobin. Biochim Biophys Acta Gen Subj 2016; 1860:1409-16. [PMID: 27062906 DOI: 10.1016/j.bbagen.2016.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 03/28/2016] [Accepted: 04/04/2016] [Indexed: 10/22/2022]
Abstract
BACKGROUND Metmyoglobin (MbFe(III)) reaction with H(2)O(2) has been a subject of study over many years. H(2)O(2) alone promotes heme destruction frequently denoted "suicide inactivation," yet the mechanism underlying H(2)O(2) dismutation associated with MbFe(III) inactivation remains obscure. METHODS MbFe(III) reaction with excess H(2)O(2) in the absence and presence of the nitroxide was studied at pH 5.3-8.1 and 25°C by direct determination of reaction rate constants using rapid-mixing stopped-flow technique, by following H(2)O(2) depletion, O(2) evolution, spectral changes of the heme protein, and the fate of the nitroxide by EPR spectroscopy. RESULTS The rates of both H(2)O(2) dismutation and heme inactivation processes depend on [MbFe(III)], [H(2)O(2)] and pH. Yet the inactivation stoichiometry is independent of these variables and each MbFe(III) molecule catalyzes the dismutation of 50±10 H(2)O(2) molecules until it is inactivated. The nitroxide catalytically enhances the catalase-like activity of MbFe(III) while protecting the heme against inactivation. The rate-determining step in the absence and presence of the nitroxide is the reduction of MbFe(IV)O by H(2)O(2) and by nitroxide, respectively. CONCLUSIONS The nitroxide effects on H(2)O(2) dismutation catalyzed by MbFe(III) demonstrate that MbFe(IV)O reduction by H(2)O(2) is the rate-determining step of this process. The proposed mechanism, which adequately fits the pro-catalytic and protective effects of the nitroxide, implies the intermediacy of a compound I-H(2)O(2) adduct, which decomposes to a MbFe(IV)O and an inactivated heme at a ratio of 25:1. GENERAL SIGNIFICANCE The effects of nitroxides are instrumental in elucidating the mechanism underlying the catalysis and inactivation routes of heme proteins.
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Affiliation(s)
- Uri Samuni
- Department of Chemistry and Biochemistry, Queens College, City University of New York, Flushing, NY 11367, USA
| | - Gideon Czapski
- The Accelerator Laboratory, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Sara Goldstein
- The Accelerator Laboratory, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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Alvarado G, Jeney V, Tóth A, Csősz É, Kalló G, Huynh AT, Hajnal C, Kalász J, Pásztor ET, Édes I, Gram M, Akerström B, Smith A, Eaton JW, Balla G, Papp Z, Balla J. Heme-induced contractile dysfunction in human cardiomyocytes caused by oxidant damage to thick filament proteins. Free Radic Biol Med 2015; 89:248-62. [PMID: 26409224 DOI: 10.1016/j.freeradbiomed.2015.07.158] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 07/21/2015] [Accepted: 07/23/2015] [Indexed: 10/23/2022]
Abstract
Intracellular free heme predisposes to oxidant-mediated tissue damage. We hypothesized that free heme causes alterations in myocardial contractility via disturbed structure and/or regulation of the contractile proteins. Isometric force production and its Ca(2+)-sensitivity (pCa50) were monitored in permeabilized human ventricular cardiomyocytes. Heme exposure altered cardiomyocyte morphology and evoked robust decreases in Ca(2+)-activated maximal active force (Fo) while increasing Ca(2+)-independent passive force (F passive). Heme treatments, either alone or in combination with H2O2, did not affect pCa50. The increase in F passive started at 3 µM heme exposure and could be partially reversed by the antioxidant dithiothreitol. Protein sulfhydryl (SH) groups of thick myofilament content decreased and sulfenic acid formation increased after treatment with heme. Partial restoration in the SH group content was observed in a protein running at 140 kDa after treatment with dithiothreitol, but not in other proteins, such as filamin C, myosin heavy chain, cardiac myosin binding protein C, and α-actinin. Importantly, binding of heme to hemopexin or alpha-1-microglobulin prevented its effects on cardiomyocyte contractility, suggesting an allosteric effect. In line with this, free heme directly bound to myosin light chain 1 in human cardiomyocytes. Our observations suggest that free heme modifies cardiac contractile proteins via posttranslational protein modifications and via binding to myosin light chain 1, leading to severe contractile dysfunction. This may contribute to systolic and diastolic cardiac dysfunctions in hemolytic diseases, heart failure, and myocardial ischemia-reperfusion injury.
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Affiliation(s)
- Gerardo Alvarado
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; Department of Nephrology, Institute of Internal Medicine, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Viktória Jeney
- Department of Nephrology, Institute of Internal Medicine, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; MTA-DE Vascular Biology, Thrombosis and Hemostasis Research Group, Hungarian Academy of Sciences, H-4032 Debrecen, Hungary
| | - Attila Tóth
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Éva Csősz
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Gergő Kalló
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - An T Huynh
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Csaba Hajnal
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Judit Kalász
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Enikő T Pásztor
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - István Édes
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Magnus Gram
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Bo Akerström
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Ann Smith
- School of Biological Sciences, University of Missouri-Kansas City, MO, USA
| | - John W Eaton
- Molecular Targets Program, James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40059, USA
| | - György Balla
- MTA-DE Vascular Biology, Thrombosis and Hemostasis Research Group, Hungarian Academy of Sciences, H-4032 Debrecen, Hungary; Institute of Pediatrics, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Zoltán Papp
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - József Balla
- Department of Nephrology, Institute of Internal Medicine, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; MTA-DE Vascular Biology, Thrombosis and Hemostasis Research Group, Hungarian Academy of Sciences, H-4032 Debrecen, Hungary.
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17
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Kassa T, Jana S, Strader MB, Meng F, Jia Y, Wilson MT, Alayash AI. Sickle Cell Hemoglobin in the Ferryl State Promotes βCys-93 Oxidation and Mitochondrial Dysfunction in Epithelial Lung Cells (E10). J Biol Chem 2015; 290:27939-58. [PMID: 26396189 DOI: 10.1074/jbc.m115.651257] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Indexed: 01/02/2023] Open
Abstract
Polymerization of intraerythrocytic deoxyhemoglobin S (HbS) is the primary molecular event that leads to hemolytic anemia in sickle cell disease (SCD). We reasoned that HbS may contribute to the complex pathophysiology of SCD in part due to its pseudoperoxidase activity. We compared oxidation reactions and the turnover of oxidation intermediates of purified human HbS and HbA. Hydrogen peroxide (H2O2) drives a catalytic cycle that includes the following three distinct steps: 1) initial oxidation of ferrous (oxy) to ferryl Hb; 2) autoreduction of the ferryl intermediate to ferric (metHb); and 3) reaction of metHb with an additional H2O2 molecule to regenerate the ferryl intermediate. Ferrous and ferric forms of both proteins underwent initial oxidation to the ferryl heme in the presence of H2O2 at equal rates. However, the rate of autoreduction of ferryl to the ferric form was slower in the HbS solutions. Using quantitative mass spectrometry and the spin trap, 5,5-dimethyl-1-pyrroline-N-oxide, we found more irreversibly oxidized βCys-93in HbS than in HbA. Incubation of the ferric or ferryl HbS with cultured lung epithelial cells (E10) induced a drop in mitochondrial oxygen consumption rate and impairment of cellular bioenergetics that was related to the redox state of the iron. Ferryl HbS induced a substantial drop in the mitochondrial transmembrane potential and increases in cytosolic heme oxygenase (HO-1) expression and mitochondrial colocalization in E10 cells. Thus, highly oxidizing ferryl Hb and heme, the product of oxidation, may be central to the evolution of vasculopathy in SCD and may suggest therapeutic modalities that interrupt heme-mediated inflammation.
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Affiliation(s)
- Tigist Kassa
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Sirsendu Jana
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Michael Brad Strader
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Fantao Meng
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Yiping Jia
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
| | - Michael T Wilson
- the Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Abdu I Alayash
- From the Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993 and
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18
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Lin YW. The broad diversity of heme-protein cross-links: An overview. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1854:844-59. [DOI: 10.1016/j.bbapap.2015.04.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 03/26/2015] [Accepted: 04/17/2015] [Indexed: 12/30/2022]
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19
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Yan DJ, Li W, Xiang Y, Wen GB, Lin YW, Tan X. A Novel Tyrosine-Heme CO Covalent Linkage in F43Y Myoglobin: A New Post-translational Modification of Heme Proteins. Chembiochem 2014; 16:47-50. [DOI: 10.1002/cbic.201402504] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Indexed: 12/18/2022]
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20
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Cedervall P, Hooper AB, Wilmot CM. Structural Studies of Hydroxylamine Oxidoreductase Reveal a Unique Heme Cofactor and a Previously Unidentified Interaction Partner. Biochemistry 2013; 52:6211-8. [DOI: 10.1021/bi400960w] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Peder Cedervall
- Department
of Biochemistry,
Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Alan B. Hooper
- Department
of Biochemistry,
Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Carrie M. Wilmot
- Department
of Biochemistry,
Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
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21
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Mollan TL, Abraham B, Strader MB, Jia Y, Lozier JN, Olson JS, Alayash AI. Familial secondary erythrocytosis due to increased oxygen affinity is caused by destabilization of the T state of hemoglobin Brigham (α₂β₂(Pro100Leu)). Protein Sci 2012; 21:1444-55. [PMID: 22821886 DOI: 10.1002/pro.2130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 06/19/2012] [Accepted: 07/12/2012] [Indexed: 02/02/2023]
Abstract
Hemoglobin Brigham (β Pro100 to Leu) was first reported in a patient with familial erythrocytosis. Erythrocytes of an affected individual from the same family contain both HbA and Hb Brigham and exhibit elevated O₂ affinity compared with normal cells (P₅₀ = 23 mm Hg vs. 31 mmHg at pH 7.4 at 37°C). O₂ affinities measured for hemolysates were sensitive to changes in pH or chloride concentrations, indicating little change in the Bohr and Chloride effects. Hb Brigham was separated from normal HbA by nondenaturing cation exchange liquid chromatography, and the amino acid substitution was verified by mass spectrometry. The properties of Hb Brigham isolated from the patient's blood were then compared with those of recombinant Hb Brigham expressed in Escherichia coli. Kinetic experiments suggest that the rate constants for ligand binding and release in the high (R) and low (T) affinity quaternary states of Hb Brigham are similar to those of native hemoglobin. However, the Brigham mutation decreases the T to R equilibrium constant (L) which accelerates the switch to the R state during ligand binding to deoxy-Hb, increasing the rate of association by approximately twofold, and decelerates the switch during ligand dissociation from HbO₂, decreasing the rate approximately twofold. These kinetic data help explain the high O₂ affinity characteristics of Hb Brigham and provide further evidence for the importance of the contribution of Pro100 to intersubunit contacts and stabilization of the T quaternary structure.
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Affiliation(s)
- Todd L Mollan
- Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA
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22
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Nagao S, Asami O, Yasui H, Hirota S. Efficient reduction of Cys110 thiyl radical by glutathione in human myoglobin. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:480-6. [DOI: 10.1016/j.bbapap.2011.01.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 12/28/2010] [Accepted: 01/13/2011] [Indexed: 11/16/2022]
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23
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Bokiej M, Livermore AT, Harris AW, Onishi AC, Sandwick RK. Ribose sugars generate internal glycation cross-links in horse heart myoglobin. Biochem Biophys Res Commun 2011; 407:191-6. [PMID: 21376016 DOI: 10.1016/j.bbrc.2011.02.138] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 02/26/2011] [Indexed: 11/25/2022]
Abstract
Glycation of horse heart metmyoglobin with d-ribose 5-phosphate (R5P), d-2-deoxyribose 5-phosphate (dR5P), and d-ribose with inorganic phosphate at 37°C generates an altered protein (Myo-X) with increased SDS-PAGE mobility. The novel protein product has been observed only for reactions with the protein myoglobin and it is not evident with other common sugars reacted over a 1 week period. Myo-X is first observed at 1-2 days at 37°C along with a second form that is consistent in mass with that of myoglobin attached to several sugars. MALDI mass spectrometry and other techniques show no evidence of the cleavage of a peptide from the myoglobin chain. Apomyoglobin in reaction with R5P also exhibited this protein form suggesting its occurrence was not heme-related. While significant amounts of O(2)(-) and H(2)O(2) are generated during the R5P glycation reaction, they do not appear to play roles in the formation of the new form. The modification is likely due to an internal cross-link formed during a glycation reaction involving the N-terminus and an internal amine group; most likely the neighboring Lys133. The study shows the unique nature of these common pentose sugars in spontaneous glycation reactions with proteins.
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Affiliation(s)
- Magdalena Bokiej
- Department of Chemistry and Biochemistry, McCardell Bicentennial Hall, Middlebury College, Middlebury, VT 05753, USA
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24
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Thompson MK, Franzen S, Ghiladi RA, Reeder BJ, Svistunenko DA. Compound ES of Dehaloperoxidase Decays via Two Alternative Pathways Depending on the Conformation of the Distal Histidine. J Am Chem Soc 2010; 132:17501-10. [DOI: 10.1021/ja106620q] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew K. Thompson
- Department of Chemistry, North Carolina State University, Box 8204, Raleigh, North Carolina 27695-8204, United States, and Department of Biological Sciences, University of Essex, Colchester CO4 3SQ, United Kingdom
| | - Stefan Franzen
- Department of Chemistry, North Carolina State University, Box 8204, Raleigh, North Carolina 27695-8204, United States, and Department of Biological Sciences, University of Essex, Colchester CO4 3SQ, United Kingdom
| | - Reza A. Ghiladi
- Department of Chemistry, North Carolina State University, Box 8204, Raleigh, North Carolina 27695-8204, United States, and Department of Biological Sciences, University of Essex, Colchester CO4 3SQ, United Kingdom
| | - Brandon J. Reeder
- Department of Chemistry, North Carolina State University, Box 8204, Raleigh, North Carolina 27695-8204, United States, and Department of Biological Sciences, University of Essex, Colchester CO4 3SQ, United Kingdom
| | - Dimitri A. Svistunenko
- Department of Chemistry, North Carolina State University, Box 8204, Raleigh, North Carolina 27695-8204, United States, and Department of Biological Sciences, University of Essex, Colchester CO4 3SQ, United Kingdom
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25
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Reeder BJ. The redox activity of hemoglobins: from physiologic functions to pathologic mechanisms. Antioxid Redox Signal 2010; 13:1087-123. [PMID: 20170402 DOI: 10.1089/ars.2009.2974] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Pentacoordinate respiratory hemoproteins such as hemoglobin and myoglobin have evolved to supply cells with oxygen. However, these respiratory heme proteins are also known to function as redox enzymes, reacting with compounds such as nitric oxide and peroxides. The recent discoveries of hexacoordinate hemoglobins in vertebrates and nonsymbiotic plants suggest that the redox activity of globins is inherent to the molecule. The uncontrolled formation of radical species resulting from such redox chemistry on respiratory hemoproteins can lead to oxidative damage and cellular toxicity. In this review, we examine the functions of various globins and the mechanisms by which these globins act as redox enzymes under physiologic conditions. Evidence that redox reactions also occur under disease conditions, leading to pathologic complications, also is examined, focusing on recent discoveries showing that the ferryl oxidation state of these hemoproteins is present in these disease states in vivo. In addition, we review the latest advances in the understanding of globin redox mechanisms and how they might affect cellular signaling pathways and how they might be controlled therapeutically or, in the case of hemoglobin-based blood substitutes, through rational design.
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Affiliation(s)
- Brandon J Reeder
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, England.
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26
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Manesh KM, Santhosh P, Gopalan AI, Lee KP. Silica-Polyaniline Based Bienzyme Cholesterol Biosensor: Fabrication and Characterization. ELECTROANAL 2010. [DOI: 10.1002/elan.201000138] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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27
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Teixeira KN, Oliveira JS, Drabowski B, Bruña-Romero O, Santos AMC, Santoro MM. Analysis of the oxidase activity induced by CCl(4) and H(2)O(2) in different recombinant myoglobins. Int J Biol Macromol 2010; 47:276-82. [PMID: 20430054 DOI: 10.1016/j.ijbiomac.2010.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 04/16/2010] [Accepted: 04/19/2010] [Indexed: 11/25/2022]
Abstract
Hemoproteins may present several functions due to their prosthetic groups. After a long time, well-studied proteins such as myoglobin have surprised us with new functions. Myoglobin is a hemoprotein which has some well described and unexpected functions within the organism. Oxidase activity in standard myoglobins has been described and this activity was attributed to a covalent linkage between heme and some amino acid residues such as histidine, when myoglobins are treated with alkyl halides, and tyrosine, and when myoglobins are treated with H(2)O(2). We have found that the oxidase activity, due to H(2)O(2) treatment, can appear in different myoglobins, which presents no key residue, such as Tyr 103, for the oxidase activity previously described in the literature.
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Affiliation(s)
- Kádima N Teixeira
- Laboratory of Enzymology and Physical Chemistry of Proteins, Department of Biochemistry and Immunology, Federal University of Minas Gerais, Av. Antonio Carlos 6627, 31270-901 Belo Horizonte, Brazil.
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28
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Ali S, Farooqi H, Prasad R, Naime M, Routray I, Yadav S, Ahmad F. Boron stabilizes peroxide mediated changes in the structure of heme proteins. Int J Biol Macromol 2010; 47:109-15. [PMID: 20576510 DOI: 10.1016/j.ijbiomac.2010.05.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 05/13/2010] [Accepted: 05/17/2010] [Indexed: 11/15/2022]
Abstract
Boron is reported in this study to stabilize the structure of heme proteins exposed to peroxides. The oxidized heme protein (15 microM) was treated with H(2)O(2) (10mM) in 1M glycine-NaOH buffer (pH 9.2) at 25 degrees C in absence/presence of boron, and characterized by visible absorption spectroscopy, gel exclusion chromatography, native PAGE, HPLC and DLS. Spectral analysis of exposed heme proteins revealed a decrease in absorbance in the Soret region, which was stabilized by boron. The native PAGE analysis of exposed heme proteins showed high molecular weight products; the band intensity was lesser in presence of boron. Further, elution profile of the exposed heme proteins on Sephadex G-200 column and HPLC revealed more than one peak (aggregate formation) when compared to the respective untreated proteins. DLS, which measures the hydrodynamic radius (R(H)), was used to ascertain whether the peaks correspond to monomer, dimer or aggregate forms. The R(H) of boron pretreated heme proteins was close to R(H) of the respective heme protein. Non-heme protein RNase did not show any change when exposed to peroxide. Taken together, results conclude that boron stabilizes the structure of heme proteins, which might be due to specific sites on heme proteins that can bind to borate ions.
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Affiliation(s)
- Shakir Ali
- Department of Biochemistry, Faculty of Science, Jamia Hamdard (Hamdard University), Hamdard Nagar, New Delhi 110062, India.
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29
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Buehler PW, D'Agnillo F. Toxicological consequences of extracellular hemoglobin: biochemical and physiological perspectives. Antioxid Redox Signal 2010; 12:275-91. [PMID: 19659434 DOI: 10.1089/ars.2009.2799] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Under normal physiology, human red blood cells (RBCs) demonstrate a circulating lifespan of approximately 100-120 days with efficient removal of senescent RBCs taking place via the reticuloendothelial system, spleen, and bone marrow phagocytosis. Within this time frame, hemoglobin (Hb) is effectively protected by efficient RBC enzymatic systems designed to allow for interaction between Hb and diffusible ligands while preventing direct contact between Hb and the external environment. Under normal resting conditions, the concentration of extracellular Hb in circulation is therefore minimal and controlled by specific plasma and cellular (monocyte/macrophage) binding proteins (haptoglobin) and receptors (CD163), respectively. However, during pathological conditions leading to hemolysis, extracellular Hb concentrations exceed normal plasma and cellular binding capacities, allowing Hb to become a biologically relevant vasoactive and redox active protein within the circulation and at extravascular sites. Under conditions of genetic, drug-induced, and autoimmune hemolytic anemias, large quantities of Hb are introduced into the circulation and often lead to acute renal failure and vascular dysfunction. Interestingly, the study of chemically modified Hb for use as oxygen therapeutics has allowed for some basic understanding of extracellular Hb toxicity, particularly in the absence of functional clearance mechanisms and in circulatory antioxidant depleted states.
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Affiliation(s)
- Paul W Buehler
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA.
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30
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Acetaminophen inhibits hemoprotein-catalyzed lipid peroxidation and attenuates rhabdomyolysis-induced renal failure. Proc Natl Acad Sci U S A 2010; 107:2699-704. [PMID: 20133658 DOI: 10.1073/pnas.0910174107] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hemoproteins, hemoglobin and myoglobin, once released from cells can cause severe oxidative damage as a consequence of heme redox cycling between ferric and ferryl states that generates radical species that induce lipid peroxidation. We demonstrate in vitro that acetaminophen inhibits hemoprotein-induced lipid peroxidation by reducing ferryl heme to its ferric state and quenching globin radicals. Severe muscle injury (rhabdomyolysis) is accompanied by the release of myoglobin that becomes deposited in the kidney, causing renal injury. We previously showed in a rat model of rhabdomyolysis that redox cycling between ferric and ferryl myoglobin yields radical species that cause severe oxidative damage to the kidney. In this model, acetaminophen at therapeutic plasma concentrations significantly decreased oxidant injury in the kidney, improved renal function, and reduced renal damage. These findings also provide a hypothesis for potential therapeutic applications for acetaminophen in diseases involving hemoprotein-mediated oxidative injury.
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31
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Lardinois OM, Maltby DA, Medzihradszky KF, de Montellano PRO, Tomer KB, Mason RP, Deterding LJ. Spin scavenging analysis of myoglobin protein-centered radicals using stable nitroxide radicals: characterization of oxoammonium cation-induced modifications. Chem Res Toxicol 2009; 22:1034-49. [PMID: 19449826 DOI: 10.1021/tx9000094] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Spin scavenging combined with chromatographic and mass spectrometric procedures can, in principle, be employed to detect and identify protein-based radicals within complex biological matrices. This approach is based on the well-known ability of stable synthetic nitroxide radicals to scavenge carbon-centered radicals, forming stable diamagnetic addition products. Hence, characterization of these addition products would allow for the identification of specific free radicals. In the present work, we have explored the use of the stable nitroxide radical 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPOL) in scavenging protein-based radicals generated in a horse heart metmyoglobin/hydrogen peroxide (metMb/H(2)O(2)) system. Inclusion of a substoichiometric amount of TEMPOL in the metMb/H(2)O(2) system resulted in a complete loss of peroxyl and tyrosyl radical signals and effectively inhibited the formation of oxidatively damaged heme species, as monitored by electron paramagnetic resonance and reversed-phase liquid chromatography. Scavenging of globin radicals by TEMPOL did not lead to the formation of stable diamagnetic addition adducts; in fact, reversed-phase liquid chromatographic studies and oxygen electrode measurements indicated that TEMPOL acts as a catalyst and is recycled in this system. The oxoammonium cation generated in the course of this reaction initiated secondary reactions resulting in the formation of a free carbonyl on the N-terminal Gly-residue of the protein. This oxidative deamination was confirmed through the combined use of reversed-phase liquid chromatographic purification, tandem MS experiments, and chemical analysis (e.g., by use of 2,4-dinitrophenyl hydrazine). The results reveal the pitfalls inherent in using stable nitroxide radicals such as TEMPOL to identify sites of radical formation on hemoproteins.
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Affiliation(s)
- Olivier M Lardinois
- Laboratories of Pharmacology and Structural Biology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA.
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32
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Roy A, Sen S, Chakraborti AS. In VitroNonenzymatic Glycation Enhances the Role of Myoglobin as a Source of Oxidative Stress. Free Radic Res 2009; 38:139-46. [PMID: 15104207 DOI: 10.1080/10715160310001638038] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Metmyoglobin (Mb) was glycated by glucose in a non-enzymatic in vitro reaction. Amount of iron release from the heme pocket of myoglobin was found to be directly related with the extent of glycation. After in vitro glycation, the unchanged Mb and glycated myoglobin (GMb) were separated by ion exchange (BioRex 70) chromatography, which eliminated free iron from the protein fractions. Separated fractions of Mb and GMb were converted to their oxy forms -MbO2 and GMbO2, respectively. H2O2-induced iron release was significantly higher from GMbO2 than that from MbO2. This free iron, acting as a Fenton reagent, might produce free radicals and degrade different cell constituents. To verify this possibility, degradation of different cell constituents catalyzed by these fractions in the presence of H2O2 was studied. GMbO2 degraded arachidonic acid, deoxyribose and plasmid DNA more efficiently than MbO2. Arachidonic acid peroxidation and deoxyribose degradation were significantly inhibited by desferrioxamine (DFO), mannitol and catalase. However, besides free iron-mediated free radical reactions, role of iron of higher oxidation states, formed during interaction of H2O2 with myoglobin might also be involved in oxidative degradation processes. Formation of carbonyl content, an index of oxidative stress, was higher by GMbO2. Compared to MbO2, GMbO2 was rapidly autooxidized and co-oxidized with nitroblue tetrazolium, indicating increased rate of Mb and superoxide radical formation in GMbO2. GMb exhibited more peroxidase activity than Mb, which was positively correlated with ferrylmyoglobin formation in the presence of H2O2. These findings correlate glycation-induced modification of myoglobin and a mechanism of increased formation of free radicals. Although myoglobin glycation is not significant within muscle cells, free myoglobin in circulation, if becomes glycated, may pose a serious threat by eliciting oxidative stress, particularly in diabetic patients.
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Affiliation(s)
- Anjana Roy
- Department of Biophysics, Molecular Biology and Genetics, University of Calcutta, 92, Acharyya Prafulla Chandra Road, Kolkata 700009, India
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33
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Oxidation of myosin by haem proteins generates myosin radicals and protein cross-links. Biochem J 2008; 410:565-74. [DOI: 10.1042/bj20071107] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Previous studies have reported that myosin can be modified by oxidative stress and particularly by activated haem proteins. These reactions have been implicated in changes in the properties of this protein in food samples (changes in meat tenderness and palatability), in human physiology (alteration of myocyte function and force generation) and in disease (e.g. cardiomyopathy, chronic heart failure). The oxidant species, mechanisms of reaction and consequences of these reactions are incompletely characterized. In the present study, the nature of the transient species generated on myosin as a result of the reaction with activated haem proteins (horseradish peroxidase/H2O2 and met-myoglobin/H2O2) has been investigated by EPR spectroscopy and amino-acid consumption, product formation has been characterized by HPLC, and changes in protein integrity have been determined by SDS/PAGE. Multiple radical species have been detected by EPR in both the presence and the absence of spin traps. Evidence has been obtained for the presence of thiyl, tyrosyl and other unidentified radical species on myosin as a result of damage-transfer from oxidized myoglobin or horseradish peroxidase. The generation of thiyl and tyrosyl radicals is consistent with the observed consumption of cysteine and tyrosine residues, the detection of di-tyrosine by HPLC and the detection of both reducible (disulfide bond) and non-reducible cross-links between myosin molecules by SDS/PAGE. The time course of radical formation on myosin, product generation and cross-link induction are consistent with these processes being interlinked. These changes are consistent with the altered function and properties of myosin in muscle tissue exposed to oxidative stress arising from disease or from food processing.
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Reeder BJ, Hider RC, Wilson MT. Iron chelators can protect against oxidative stress through ferryl heme reduction. Free Radic Biol Med 2008; 44:264-73. [PMID: 18215735 DOI: 10.1016/j.freeradbiomed.2007.08.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Revised: 08/03/2007] [Accepted: 08/06/2007] [Indexed: 10/22/2022]
Abstract
Iron chelators such as desferrioxamine have been shown to ameliorate oxidative damage in vivo. The mechanism of this therapeutic action under non-iron-overload conditions is, however, complex, as desferrioxamine has properties that can impact on oxidative damage independent of its capacity to act as an iron chelator. Desferrioxamine can act as a reducing agent to remove cytotoxic ferryl myoglobin and hemoglobin and has recently been shown to prevent the formation of a highly cytotoxic heme-to-protein cross-linked derivative of myoglobin. In this study we have examined the effects of a wide range of iron chelators, including the clinically used hydroxypyridinone CP20 (deferriprone), on the stability of ferryl myoglobin and on the formation of heme-to-protein cross-linking. We show that all hydroxypyridinones, as well as many other iron chelators, are efficient reducing agents of ferryl myoglobin. These compounds are also effective at preventing the formation of cytotoxic derivatives of myoglobin such as heme-to-protein cross-linking. These results show that the use of iron chelators in vivo may ameliorate oxidative damage under conditions of non-iron overload by at least two mechanisms. The antioxidant effects of chelators in vivo cannot, therefore, be attributed solely to iron chelation.
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Affiliation(s)
- Brandon J Reeder
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, UK.
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35
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Lu H, Rusling JF, Hu N. Protecting peroxidase activity of multilayer enzyme-polyion films using outer catalase layers. J Phys Chem B 2007; 111:14378-86. [PMID: 18052272 PMCID: PMC2546493 DOI: 10.1021/jp076036w] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Films constructed layer-by-layer on electrodes with architecture {protein/hyaluronic acid (HA)}n containing myoglobin (Mb) or horseradish peroxidase (HRP) were protected against protein damage by H2O2 by using outer catalase layers. Peroxidase activity for substrate oxidation requires activation by H2O2, but {protein/HA}n films without outer catalase layers are damaged slowly and irreversibly by H2O2. The rate and extent of damage were decreased dramatically by adding outer catalase layers to decompose H2O2. Comparative studies suggest that protection results from catalase decomposing a fraction of the H2O2 as it enters the film, rather than by an in-film diffusion barrier. The outer catalase layers controlled the rate of H2O2 entry into inner regions of the film, and they biased the system to favor electrocatalytic peroxide reduction over enzyme damage. Catalase-protected {protein/HA}n films had an increased linear concentration range for H2O2 detection. This approach offers an effective way to protect biosensors from damage by H2O2.
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Affiliation(s)
- Haiyun Lu
- Department of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - James F. Rusling
- Department of Chemistry, University of Connecticut, U-60, Storrs, CT 06269-3060, USA
- Department of Pharmacology, University of Connecticut Health Center, Farmington, CT 06032, USA
| | - Naifei Hu
- Department of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
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36
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Pipirou Z, Bottrill AR, Svistunenko DA, Efimov I, Basran J, Mistry SC, Cooper CE, Raven EL. The reactivity of heme in biological systems: autocatalytic formation of both tyrosine-heme and tryptophan-heme covalent links in a single protein architecture. Biochemistry 2007; 46:13269-78. [PMID: 17958400 DOI: 10.1021/bi7015316] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have previously shown that introduction of an engineered Met160 residue in ascorbate peroxidase (S160M variant) leads to the formation of a covalent link between Met160 and the heme vinyl group [Metcalfe, C. L., et al. (2004) J. Am. Chem. Soc. 126, 16242-16248]. In this work, we have used electronic spectroscopy, HPLC, and mass spectrometry to show that the introduction of a tyrosine residue at the same position (S160Y variant) leads, similarly, to the formation of a heme-tyrosine covalent link in an autocatalytic reaction that also leads to formation of a second covalent link from the heme to Trp41 [Pipirou, Z., et al. (2007) Biochemistry 46, 2174-2180]. Stopped-flow and EPR data implicate the involvement of a tyrosyl radical in the reaction mechanism. The results indicate that the heme can support the formation of different types of covalent links under appropriate conditions. The generality of this idea is discussed in the context of other heme enzymes.
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Affiliation(s)
- Zoi Pipirou
- Department of Chemistry, Henry Wellcome Building, University of Leicester, University Road, Leicester, LE1 7RH, England
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37
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Watanabe Y, Nakajima H, Ueno T. Reactivities of oxo and peroxo intermediates studied by hemoprotein mutants. Acc Chem Res 2007; 40:554-62. [PMID: 17567089 DOI: 10.1021/ar600046a] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of myoglobin mutants, in which distal sites are modified by site-directed mutagenesis, are able to catalyze peroxidase, catalase, and P450 reactions even though their proximal histidine ligands are intact. More importantly, reactions of P450, catalase, and peroxidase substrates and compound I of myoglobin mutants can be observed spectroscopically. Thus, detailed oxidation mechanisms were examined. On the basis of these results, we suggest that the different reactivities of P450, catalase, and peroxidase are mainly caused by their active site structures, but not the axial ligand. We have also prepared compound 0 under physiological conditions by employing a mutant of cytochrome c 552. Compound 0 is not able to oxidize ascorbic acid.
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Affiliation(s)
- Yoshihito Watanabe
- Research Center for Materials Science and Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
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38
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Grey CE, Hedström M, Adlercreutz P. A Mass Spectrometric Investigation of Native and Oxidatively Inactivated Chloroperoxidase. Chembiochem 2007; 8:1055-62. [PMID: 17492739 DOI: 10.1002/cbic.200700091] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The enzyme chloroperoxidase (CPO) found in Caldariomyces fumago is able to catalyze several stereoselective oxidation reactions by using a clean oxidant, usually hydrogen peroxide (H(2)O(2)), without the need for expensive cofactor generation. CPO's lack of operational stability, however, is a major limitation for its commercial use. In the present study, a capillary-LC on-line trypsin-digestion system combined with reversed-phase chromatography and mass spectrometric detection was optimized for studying the primary sequence of CPO. Samples containing native CPO, CPO treated with H(2)O(2), and CPO oxidatively inactivated by the use of indole and H(2)O(2) were analyzed and compared. Three oxidized peptides were found in the samples treated with H(2)O(2). Two additional oxidized peptides were found in the CPO samples that were completely inactivated, one of which contained an oxidized cysteine residue, Cys50, which is an essential amino acid due to its function as the axial ligand to the iron in the heme--the prosthetic group in CPO. In addition, the heme group was absent in the inactivated samples but was readily detected in other samples.
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Affiliation(s)
- Carl Elovson Grey
- Department of Biotechnology, Lund University, P.O. Box 124, SE-22 100 Lund, Sweden
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39
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Jia Y, Buehler PW, Boykins RA, Venable RM, Alayash AI. Structural basis of peroxide-mediated changes in human hemoglobin: a novel oxidative pathway. J Biol Chem 2006; 282:4894-4907. [PMID: 17178725 DOI: 10.1074/jbc.m609955200] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hydrogen peroxide (H(2)O(2)) triggers a redox cycle between ferric and ferryl hemoglobin (Hb) leading to the formation of a transient protein radical and a covalent hemeprotein cross-link. Addition of H(2)O(2) to highly purified human hemoglobin (HbA(0)) induced structural changes that primarily resided within beta subunits followed by the internalization of the heme moiety within alpha subunits. These modifications were observed when an equal molar concentration of H(2)O(2) was added to HbA(0) yet became more abundant with greater concentrations of H(2)O(2). Mass spectrometric and amino acid analysis revealed for the first time that betaCys-93 and betaCys-112 were oxidized extensively and irreversibly to cysteic acid when HbA(0) was treated with H(2)O(2). Oxidation of further amino acids in HbA(0) exclusive to the beta-globin chain included modification of betaTrp-15 to oxyindolyl and kynureninyl products as well as betaMet-55 to methionine sulfoxide. These findings may therefore explain the premature collapse of the beta subunits as a result of the H(2)O(2) attack. Analysis of a tryptic digest of the main reversed phase-high pressure liquid chromatography fraction revealed two alpha-peptide fragments (alpha128-alpha139) and a heme moiety with the loss of iron, cross-linked between alphaSer-138 and the porphyrin ring. The novel oxidative pathway of HbA(0) modification detailed here may explain the diverse oxidative, toxic, and potentially immunogenic effects associated with the release of hemoglobin from red blood cells during hemolytic diseases and/or when cell-free Hb is used as a blood substitute.
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Affiliation(s)
- Yiping Jia
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, and the Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892
| | - Paul W Buehler
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, and the Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892
| | - Robert A Boykins
- Laboratory of Biophysics, Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, and
| | - Richard M Venable
- Membrane Biophysics Section, Laboratory of Computational Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892
| | - Abdu I Alayash
- Laboratory of Biochemistry and Vascular Biology, Division of Hematology, and the Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892.
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40
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Dunne J, Caron A, Menu P, Alayash A, Buehler P, Wilson M, Silaghi-Dumitrescu R, Faivre B, Cooper C. Ascorbate removes key precursors to oxidative damage by cell-free haemoglobin in vitro and in vivo. Biochem J 2006; 399:513-24. [PMID: 16848758 PMCID: PMC1615907 DOI: 10.1042/bj20060341] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2006] [Revised: 06/19/2006] [Accepted: 07/18/2006] [Indexed: 01/05/2023]
Abstract
Haemoglobin initiates free radical chemistry. In particular, the interactions of peroxides with the ferric (met) species of haemoglobin generate two strong oxidants: ferryl iron and a protein-bound free radical. We have studied the endogenous defences to this reactive chemistry in a rabbit model following 20% exchange transfusion with cell-free haemoglobin stabilized in tetrameric form [via cross-linking with bis-(3,5-dibromosalicyl)fumarate]. The transfusate contained 95% oxyhaemoglobin, 5% methaemoglobin and 25 microM free iron. EPR spectroscopy revealed that the free iron in the transfusate was rendered redox inactive by rapid binding to transferrin. Methaemoglobin was reduced to oxyhaemoglobin by a slower process (t(1/2) = 1 h). No globin-bound free radicals were detected in the plasma. These redox defences could be fully attributed to a novel multifunctional role of plasma ascorbate in removing key precursors of oxidative damage. Ascorbate is able to effectively reduce plasma methaemoglobin, ferryl haemoglobin and globin radicals. The ascorbyl free radicals formed are efficiently re-reduced by the erythrocyte membrane-bound reductase (which itself uses intra-erythrocyte ascorbate as an electron donor). As well as relating to the toxicity of haemoglobin-based oxygen carriers, these findings have implications for situations where haem proteins exist outside the protective cell environment, e.g. haemolytic anaemias, subarachnoid haemorrhage, rhabdomyolysis.
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Affiliation(s)
- Jacqueline Dunne
- *Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Alexis Caron
- †Laboratoire Hématologie-Physiologie, Faculté de Pharmacie, Université Henri Poincaré, 5–7 rue Albert Lebrun, BP 403, F-54001 Nancy cedex, France
| | - Patrick Menu
- †Laboratoire Hématologie-Physiologie, Faculté de Pharmacie, Université Henri Poincaré, 5–7 rue Albert Lebrun, BP 403, F-54001 Nancy cedex, France
| | - Abdu I. Alayash
- ‡Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and Research, Food and Drug Administration, NIH Building 29, Room 112, Bethesda, MD 20892, U.S.A
| | - Paul W. Buehler
- ‡Laboratory of Biochemistry and Vascular Biology, Division of Hematology, Center for Biologics Evaluation and Research, Food and Drug Administration, NIH Building 29, Room 112, Bethesda, MD 20892, U.S.A
| | - Michael T. Wilson
- *Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Radu Silaghi-Dumitrescu
- *Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Beatrice Faivre
- †Laboratoire Hématologie-Physiologie, Faculté de Pharmacie, Université Henri Poincaré, 5–7 rue Albert Lebrun, BP 403, F-54001 Nancy cedex, France
| | - Chris E. Cooper
- *Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
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41
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Witting PK, Liao WQ, Neuzil J. Expression of human myoglobin in H9c2 cells enhances toxicity to added hydrogen peroxide. Biochem Biophys Res Commun 2006; 348:485-93. [PMID: 16887098 DOI: 10.1016/j.bbrc.2006.07.077] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2006] [Accepted: 07/14/2006] [Indexed: 01/15/2023]
Abstract
Hydrogen peroxide (H2O2) is implicated in cardiac myocyte (CM) damage during myocardial ischemia-reperfusion (IR) injury. Myoglobin (Mb) is present in CM at significant concentrations and reacts with H2O2 to yield one- and two-electron oxidants that may promote myocardial injury. Paradoxically, hearts from mice lacking Mb are more susceptible to H2O2-induced dysfunction than the corresponding controls [U. Flogel, A. Godecke, L.O. Klotz, J. Schrader, Role of myoglobin in the anti-oxidant defense of the heart, FASEB J. 18 (2004) 1156-1158]. We have overexpressed wild-type or Y103F variant of human Mb in cultured CMs to test whether Mb protects against H2O2 insult. Contrary to expectation, cells expressing WT or the Y103F Mb show increased mitochondrial dysfunction and apoptosis, and decreased ATP in response to H2O2 that follows the order native < Y103F Mb < WT human Mb consistent with the increasing pro-oxidant activity for these proteins. These data indicate that (i) Mb promotes oxidative damage to cultured CM and (ii) Mb may be a useful target for the design of inhibitors of myocardial IR injury.
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Affiliation(s)
- Paul K Witting
- ANZAC Research Institute, Concord Hospital, Concord, NSW, Australia.
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Abstract
The erythrocyte represents a major component of the antioxidant capacity of the blood through the enzymes contained in the cell, the glutathione system, and the low-molecular-weight antioxidants of the erythrocyte membrane. A further major red blood cell contribution is in regenerating consumed redox equivalents via the oxidative pentose phosphate pathway and glutathione reductase. Moreover, its extracellular antioxidant capacity, its mobility, and the existence of reducing equivalents far in excess of its normal requirements make erythrocytes function as an effective oxidative sink in the organism. That is why red blood cell metabolism and homeostasis strongly affect the antioxidant properties of the whole body. Conversely, the relation between macrocytosis and oxidative stress has not been fully delineated. Reviewing the mechanisms involved in red blood cell homeostasis in cases of redox imbalance is crucial in identification of factors that could potentially improve erythrocyte survival and defense against oxidant damage.
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Affiliation(s)
- Argirios E Tsantes
- Laboratory of Hematology & Blood Bank Unit, Attikon General Hospital, School of Medicine, University of Athens, Greece
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43
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Vollaard NBJ, Reeder BJ, Shearman JP, Menu P, Wilson MT, Cooper CE. A new sensitive assay reveals that hemoglobin is oxidatively modified in vivo. Free Radic Biol Med 2005; 39:1216-28. [PMID: 16214037 DOI: 10.1016/j.freeradbiomed.2005.06.012] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2004] [Revised: 06/21/2005] [Accepted: 06/21/2005] [Indexed: 10/25/2022]
Abstract
Free radical formation in heme proteins is recognised as a factor in mediating the toxicity of peroxides in oxidative stress. As well as initiating free radical damage, heme proteins damage themselves. Under extreme conditions, where oxidative stress and low pH coincide (e.g., myoglobin in the kidney following rhabdomyolysis and hemoglobin in the CSF subsequent to subarachnoid hemorrhage), peroxide can induce covalent heme to protein cross-linking. In this paper we show that, even at neutral pH, the heme in hemoglobin is covalently modified by oxidation. The product, which we term OxHm, is a "green heme" iron chlorin with a distinct optical spectrum. OxHm formation can be quantitatively prevented by reductants of ferryl iron, e.g., ascorbate. We have developed a simple, robust, and reproducible HPLC assay to study the extent of OxHm formation in the red cell in vivo. We show that hemoglobin is oxidatively damaged even in normal blood; approximately 1 in 2,000 heme groups exist as OxHm in the steady state. We used a simple model (physical exercise) to demonstrate that OxHm increases significantly during acute oxidative stress. The exercise-induced increase is short-lived, suggesting the existence of an active mechanism for repairing or removing the damaged heme proteins.
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Affiliation(s)
- Niels B J Vollaard
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
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44
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Tan WB, Cheng W, Webber A, Bhambhani A, Duff MR, Kumar CV, McLendon GL. Endonuclease-like activity of heme proteins. J Biol Inorg Chem 2005; 10:790-9. [PMID: 16208493 DOI: 10.1007/s00775-005-0028-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2005] [Accepted: 08/26/2005] [Indexed: 10/25/2022]
Abstract
Heme proteins, metmyoglobin, methemoglobin, and metcytochrome c showed unusual affinity for double-stranded DNA. Calorimetric studies show that binding of methemoglobin to calf thymus DNA (CTDNA) is weakly endothermic, and the binding constant is 4.9+/-0.7x10(5) M(-1). The Soret absorption bands of the heme proteins remained unchanged, in the presence of excess CTDNA, but a new circular dichroic band appeared at 210 nm. Helix melting studies indicated that the protein-DNA mixture denatures at a lower temperature than the individual components. Thermograms obtained by differential scanning calorimetry of the mixture indicated two distinct transitions, which are comparable to the thermograms obtained for individual components, but there was a reduction in the excess heat capacity. Activation of heme proteins by hydrogen peroxide resulted in the formation of high valent Fe(IV) oxo intermediates, and CTDNA reacted rapidly under these conditions. The rate was first-order in DNA concentration, and this reactivity resulted in DNA strand cleavage. Upon activation with hydrogen peroxide, for example, the heme proteins converted the supercoiled pUC18 DNA into nicked circular and linear DNA. No reaction occurred in the absence of the heme protein, or hydrogen peroxide. These data clearly indicate a novel property of several heme proteins, and this is first report of the endonuclease-like activity of the heme proteins.
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Affiliation(s)
- Willy B Tan
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA
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45
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Goldstein S, Samuni A. Intra- and intermolecular oxidation of oxymyoglobin and oxyhemoglobin induced by hydroxyl and carbonate radicals. Free Radic Biol Med 2005; 39:511-9. [PMID: 16043022 DOI: 10.1016/j.freeradbiomed.2005.04.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2005] [Revised: 04/03/2005] [Accepted: 04/04/2005] [Indexed: 10/25/2022]
Abstract
The mechanism of the reactions of myoglobin and hemoglobin with *OH and CO3*- in the presence of oxygen was studied using pulse and gamma-radiolysis. Unlike *NO2, which adds to the porphyrin iron, *OH and CO3*- form globin radicals. These secondary radicals oxidize the Fe(II) center through both intra- and intermolecular processes. The intermolecular pathway was further demonstrated when BSA radicals derived from *OH or CO3*- oxidized oxyhemoglobin and oxymyoglobin to their respective ferric states. The oxidation yields obtained by pulse radiolysis were lower compared to gamma-radiolysis, where the contribution of radical-radical reactions is negligible. Full oxidation yields by *OH-derived globin radicals could be achieved only at relatively high concentrations of the heme protein mainly via an intermolecular pathway. It is suggested that CO3*- reaction with the protein yields Tyr and/or Trp-derived phenoxyl radicals, which solely oxidize the porphyrin iron under gamma-radiolysis conditions. The *OH particularly adds to aromatic residues, which can undergo elimination of H2O forming the phenoxyl radical, and/or react rapidly with O2 yielding peroxyl radicals. The peroxyl radical can oxidize a neighboring porphyrin iron and/or give rise to superoxide, which neither oxidize nor reduce the porphyrin iron. The potential physiological implications of this chemistry are that hemoglobin and myoglobin, being present at relatively high concentrations, can detoxify highly oxidizing radicals yielding the respective ferric states, which are not toxic.
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Affiliation(s)
- Sara Goldstein
- Department of Physical Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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46
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Reeder BJ, Wilson MT. Desferrioxamine Inhibits Production of Cytotoxic Heme to Protein Cross-Linked Myoglobin: A Mechanism to Protect against Oxidative Stress without Iron Chelation. Chem Res Toxicol 2005; 18:1004-11. [PMID: 15962935 DOI: 10.1021/tx049660y] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The heme group of myoglobin can form a covalent bond to the protein when met (ferric) myoglobin is reacted with peroxides under acidic conditions. This heme to protein cross-linked species is highly pro-oxidant and found in the urine of patients with rhabdomyolytic-associated acute renal failure. Desferrioxamine, an iron-chelating agent used in the treatment of iron overload, is reported to be partially effective at preventing kidney failure following rhabdomyolysis. In this article, we show that in addition to its capacity as an iron chelator, desferroxamine can inhibit the peroxide-induced formation of heme to protein cross-linked myoglobin and decreases the pro-oxidant activity of both native and heme to protein cross-linked myoglobin. The mechanism of peroxidation and of heme to protein cross-linking involves the formation of ferryl intermediate (Fe(4+)=O(2-)), and it is by the reduction of this intermediate to the ferric form that desferrioxamine can exert inhibitory effects. The concentrations at which desferrioxamine inhibits the formation of heme to protein cross-linked myoglobin and prevents the pro-oxidant activity of native and oxidatively modified myoglobins are comparable to the concentrations used for in vivo studies of iron-related oxidative stress. Thus, the ameliorative effects of treatment of posthemolytic events by desferrioxamine cannot be exclusively assigned to its ability to chelate free iron.
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Affiliation(s)
- Brandon J Reeder
- Department of Biological Sciences, Central Campus, University of Essex, Wivenhoe Park, Colchester, Essex, CO4 3SQ, United Kingdom.
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Detweiler CD, Lardinois OM, Deterding LJ, de Montellano PRO, Tomer KB, Mason RP. Identification of the myoglobin tyrosyl radical by immuno-spin trapping and its dimerization. Free Radic Biol Med 2005; 38:969-76. [PMID: 15749393 DOI: 10.1016/j.freeradbiomed.2004.12.031] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Revised: 12/20/2004] [Accepted: 12/23/2004] [Indexed: 11/24/2022]
Abstract
5,5-Dimethyl-1-pyrroline N-oxide (DMPO) spin trapping in conjunction with antibodies specific for the DMPO nitrone epitope was used on hydrogen peroxide-treated sperm whale and horse heart myoglobins to determine the site of protein nitrone adduct formation. The present study demonstrates that the sperm whale myoglobin tyrosyl radical, formed by hydrogen peroxide-dependent self-peroxidation, can either react with another tyrosyl radical, resulting in a dityrosine cross-linkage, or react with the spin trap DMPO to form a diamagnetic nitrone adduct. The reaction of sperm whale myoglobin with equimolar hydrogen peroxide resulted in the formation of a myoglobin dimer detectable by electrophoresis/protein staining. Addition of DMPO resulted in the trapping of the globin radical, which was detected by Western blot. The location of this adduct was demonstrated to be at tyrosine-103 by MS/MS and site-specific mutagenicity. Interestingly, formation of the myoglobin dimer, which is known to be formed primarily by cross-linkage of tyrosine-151, was inhibited by the addition of DMPO.
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Affiliation(s)
- Charles D Detweiler
- Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institutes of Health, PO Box 12233, MD F0-01, Research Triangle Park, NC 27709, USA
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Svistunenko DA. Reaction of haem containing proteins and enzymes with hydroperoxides: The radical view. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2005; 1707:127-55. [PMID: 15721611 DOI: 10.1016/j.bbabio.2005.01.004] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2004] [Revised: 01/12/2005] [Accepted: 01/13/2005] [Indexed: 11/24/2022]
Abstract
The reaction between hydroperoxides and the haem group of proteins and enzymes is important for the function of many enzymes but has also been implicated in a number of pathological conditions where oxygen binding proteins interact with hydrogen peroxide or other peroxides. The haem group in the oxidized Fe3+ (ferric) state reacts with hydroperoxides with a formation of the Fe4+=O (oxoferryl) haem state and a free radical primarily located on the pi-system of the haem. The radical is then transferred to an amino acid residue of the protein and undergoes further transfer and transformation processes. The free radicals formed in this reaction are reviewed for a number of proteins and enzymes. Their previously published EPR spectra are analysed in a comparative way. The radicals directly detected in most systems are tyrosyl radicals and the peroxyl radicals formed on tryptophan and possibly cysteine. The locations of the radicals in the proteins have been reported as follows: Tyr133 in soybean leghaemoglobin; alphaTyr42, alphaTrp14, betaTrp15, betaCys93, (alphaTyr24-alphaHis20), all in the alpha- and beta-subunits of human haemoglobin; Tyr103, Tyr151 and Trp14 in sperm whale myoglobin; Tyr103, Tyr146 and Trp14 in horse myoglobin; Trp14, Tyr103 and Cys110 in human Mb. The sequence of events leading to radical formation, transformation and transfer, both intra- and intermolecularly, is considered. The free radicals induced by peroxides in the enzymes are reviewed. Those include: lignin peroxidase, cytochrome c peroxidase, cytochrome c oxidase, turnip isoperoxidase 7, bovine catalase, two isoforms of prostaglandin H synthase, Mycobacterium tuberculosis and Synechocystis PCC6803 catalase-peroxidases.
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Affiliation(s)
- Dimitri A Svistunenko
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ, United Kingdom.
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Reeder BJ, Svistunenko DA, Cooper CE, Wilson MT. The radical and redox chemistry of myoglobin and hemoglobin: from in vitro studies to human pathology. Antioxid Redox Signal 2004; 6:954-66. [PMID: 15548893 DOI: 10.1089/ars.2004.6.954] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Recent research has shown that myoglobin and hemoglobin play important roles in the pathology of certain disease states, such as renal dysfunction following rhabdomyolysis and vasospasm following subarachnoid hemorrhages. These pathologies are linked to the interaction of peroxides with heme proteins to initiate oxidative reactions, including generation of powerful vasoactive molecules (the isoprostanes) from free and membrane- bound lipids. This review focuses on the peroxide-induced formation of radicals, their assignment to specific protein residues, and the pseudoperoxidase and prooxidant activities of the heme proteins. The discovery of heme to protein cross-linked forms of myoglobin and hemoglobin in vivo, definitive markers of the participation of these heme proteins in oxidative reactions, and the recent results from heme oxygenase knockout/knockin animal model studies, indicate that higher oxidation states (ferryl) of heme proteins and their associated radicals play a major role in the mechanisms of pathology.
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Affiliation(s)
- Brandon J Reeder
- Department of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex, UK.
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Konovalova TA, Kispert LD, van Tol J, Brunel LC. Multifrequency High-Field Electron Paramagnetic Resonance Characterization of the Peroxyl Radical Location in Horse Heart Myoglobin Oxidized by H2O2. J Phys Chem B 2004. [DOI: 10.1021/jp0313425] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tatyana A. Konovalova
- Department of Chemistry, Box 870336, University of Alabama, Tuscaloosa, Alabama 35487, and Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310
| | - Lowell D. Kispert
- Department of Chemistry, Box 870336, University of Alabama, Tuscaloosa, Alabama 35487, and Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310
| | - Johan van Tol
- Department of Chemistry, Box 870336, University of Alabama, Tuscaloosa, Alabama 35487, and Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310
| | - Louis-Claude Brunel
- Department of Chemistry, Box 870336, University of Alabama, Tuscaloosa, Alabama 35487, and Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310
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