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Schaich KM. Epoxides: an underestimated lipid oxidation product. Free Radic Res 2023:1-48. [PMID: 38124354 DOI: 10.1080/10715762.2023.2277142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 08/09/2023] [Indexed: 12/23/2023]
Abstract
Immense gains in understanding of mechanisms and effects of lipid oxidation have been achieved in the nearly 90 years over which lipid oxidation has been an active research focus. Even so, the substantial questions still being raised about lipid oxidation in this special issue show clearly that missing pieces remain and must be considered for full accounting of this important reaction in any system. In this context, epoxides are spotlighted as a critical overlooked product of lipid autoxidation - underestimated in analysis, underestimated in presence as a functionally active and competitive intermediate and product of lipid oxidation, and underestimated in potential contributions to impact of lipid oxidation on other molecules and cell functions. Logical reasons for ignoring or not finding epoxides are offered in historical development of lipid oxidation knowledge. Reactions generating lipid epoxides in autoxidation are reviewed, limitations in detecting and tracking epoxides are outlined to explain why epoxides may not be detected when they should be present, and justifications for increased research and analysis of epoxides are argued. The main goal is to provide a context for recognizing epoxides as critical products that must be accounted for in determining the state rather than extent of lipid oxidation and in tracking its consequences in oils, foods, personal care products, and tissues. A secondary goal is to stimulate new research using contemporary analyses to fill in the gaps of knowledge about epoxide formation, structure, and reactions in lipid autoxidation.
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Affiliation(s)
- Karen M Schaich
- Department of Food Science, Rutgers University, New Brunswick, NJ, USA
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2
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Santiago PH, Aiube CM, de Macedo JL, Gatto CC. Hydrazone-derived copper(II) coordination polymer as a selective liquid-phase catalyst: Synthesis, crystal structure and performance towards benzyl alcohol oxidation. MOLECULAR CATALYSIS 2020. [DOI: 10.1016/j.mcat.2020.111177] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Varkhede N, Bommana R, Schöneich C, Forrest ML. Proteolysis and Oxidation of Therapeutic Proteins After Intradermal or Subcutaneous Administration. J Pharm Sci 2020; 109:191-205. [PMID: 31408633 PMCID: PMC6937400 DOI: 10.1016/j.xphs.2019.08.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/05/2019] [Accepted: 08/06/2019] [Indexed: 12/12/2022]
Abstract
The intradermal (ID) and subcutaneous (SC) routes are commonly used for therapeutic proteins (TPs) and vaccines; however, the bioavailability of TPs is typically less than small molecule drugs given via the same routes. Proteolytic enzymes in the dermal, SC, and lymphatic tissues may be responsible for the loss of TPs. In addition, the TPs may be exposed to reactive oxygen species generated in the SC tissue and the lymphatic system in response to injection-related trauma and impurities within the formulation. The reactive oxygen species can oxidize TPs to alter their efficacy and immunogenicity potential. Mechanistic understandings of the dominant proteolysis and oxidative routes are useful in the drug discovery process, formulation development, and to assess the potential for immunogenicity and altered pharmacokinetics (PK). Furthermore, in vitro tools representing the ID or SC and lymphatic system can be used to evaluate the extent of proteolysis of the TPs after the injection and before systemic entry. The in vitro clearance data may be included in physiologically based pharmacokinetic models for improved PK predictions. In this review, we have summarized various physiological factors responsible for proteolysis and oxidation of TPs after ID and SC administration.
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Affiliation(s)
- Ninad Varkhede
- Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047; Department of Pharmacokinetics, Pharmacodynamics & Drug Metabolism (PPDM), Merck Research Laboratories, West Point, Pennsylvania 19486
| | - Rupesh Bommana
- Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047; MedImmune, Gaithersburg, Maryland 20878
| | - Christian Schöneich
- Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047
| | - M Laird Forrest
- Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047.
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Chemical Basis of Reactive Oxygen Species Reactivity and Involvement in Neurodegenerative Diseases. Int J Mol Sci 2019; 20:ijms20102407. [PMID: 31096608 PMCID: PMC6566277 DOI: 10.3390/ijms20102407] [Citation(s) in RCA: 400] [Impact Index Per Article: 80.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/09/2019] [Accepted: 05/13/2019] [Indexed: 12/12/2022] Open
Abstract
Increasing numbers of individuals suffer from neurodegenerative diseases, which are characterized by progressive loss of neurons. Oxidative stress, in particular, the overproduction of Reactive Oxygen Species (ROS), play an important role in the development of these diseases, as evidenced by the detection of products of lipid, protein and DNA oxidation in vivo. Even if they participate in cell signaling and metabolism regulation, ROS are also formidable weapons against most of the biological materials because of their intrinsic nature. By nature too, neurons are particularly sensitive to oxidation because of their high polyunsaturated fatty acid content, weak antioxidant defense and high oxygen consumption. Thus, the overproduction of ROS in neurons appears as particularly deleterious and the mechanisms involved in oxidative degradation of biomolecules are numerous and complexes. This review highlights the production and regulation of ROS, their chemical properties, both from kinetic and thermodynamic points of view, the links between them, and their implication in neurodegenerative diseases.
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Abstract
Proteins are major targets for radicals and two-electron oxidants in biological systems due to their abundance and high rate constants for reaction. With highly reactive radicals damage occurs at multiple side-chain and backbone sites. Less reactive species show greater selectivity with regard to the residues targeted and their spatial location. Modification can result in increased side-chain hydrophilicity, side-chain and backbone fragmentation, aggregation via covalent cross-linking or hydrophobic interactions, protein unfolding and altered conformation, altered interactions with biological partners and modified turnover. In the presence of O2, high yields of peroxyl radicals and peroxides (protein peroxidation) are formed; the latter account for up to 70% of the initial oxidant flux. Protein peroxides can oxidize both proteins and other targets. One-electron reduction results in additional radicals and chain reactions with alcohols and carbonyls as major products; the latter are commonly used markers of protein damage. Direct oxidation of cysteine (and less commonly) methionine residues is a major reaction; this is typically faster than with H2O2, and results in altered protein activity and function. Unlike H2O2, which is rapidly removed by protective enzymes, protein peroxides are only slowly removed, and catabolism is a major fate. Although turnover of modified proteins by proteasomal and lysosomal enzymes, and other proteases (e.g. mitochondrial Lon), can be efficient, protein hydroperoxides inhibit these pathways and this may contribute to the accumulation of modified proteins in cells. Available evidence supports an association between protein oxidation and multiple human pathologies, but whether this link is causal remains to be established.
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Affiliation(s)
- Michael J Davies
- Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Blegdamsvej 3, Copenhagen 2200, Denmark
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YANG W, YIN B, GUO C, TAN Z, ZHANG L. EPR Study of Cumene Hydroperoxide Decomposition Catalyzed by Tetra-(p-chlorophenyl)porphinatomanganese Chloride. CHINESE JOURNAL OF CATALYSIS 2010. [DOI: 10.1016/s1872-2067(09)60068-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Crean C, Shao J, Yun BH, Geacintov NE, Shafirovich V. The role of one-electron reduction of lipid hydroperoxides in causing DNA damage. Chemistry 2009; 15:10634-40. [PMID: 19746460 DOI: 10.1002/chem.200900500] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The in vivo metabolism of plasma lipids generates lipid hydroperoxides that, upon one-electron reduction, give rise to a wide spectrum of genotoxic unsaturated aldehydes and epoxides. These metabolites react with cellular DNA to form a variety of pre-mutagenic DNA lesions. The mechanisms of action of the radical precursors of these genotoxic electrophiles are poorly understood. In this work we investigated the nature of DNA products formed by a one-electron reduction of (13S)-hydroperoxy-(9Z,11E)-octadecadienoic acid (13S-HPODE), a typical lipid molecule, and the reactions of the free radicals thus generated with neutral guanine radicals, G(-H)(*). A novel approach was devised to generate these intermediates in solution. The two-photon-induced ionization of 2-aminopurine (2AP) within the 2'-deoxyoligonucleotide 5'-d(CC[2AP]TCGCTACC) by intense nanosecond 308 nm excimer laser pulses was employed to simultaneously generate hydrated electrons and radical cations 2AP(*+). The latter radicals either in cationic or neutral forms, rapidly oxidize the nearby G base to form G(-H)(*). In deoxygenated buffer solutions (pH 7.5), the hydrated electrons rapidly reduce 13S-HPODE and the highly unstable alkoxyl radicals formed undergo a prompt beta-scission to pentyl radicals that readily combine with G(-H)(*). Two novel guanine products in these oligonucleotides, 8-pentyl- and N(2)-pentylguanine, were identified. It is shown that the DNA secondary structure significantly affects the ratio of 8-pentyl- and N(2)-pentylguanine lesions that changes from 0.9:1 in single-stranded, to 1:0.2 in double-stranded oligonucleotides. The alkylation of guanine by alkyl radicals derived from lipid hydroperoxides might contribute to the genotoxic modification of cellular DNA under hypoxic conditions. Thus, further research is warranted on the detection of pentylguanine lesions and other alkylguanines in vivo.
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Affiliation(s)
- Conor Crean
- Chemistry Department, 31 Washington Place, New York University, New York, NY 10003-5180, USA
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Argyropoulos DS, Li H, Gaspar AR, Smith K, Lucia LA, Rojas OJ. Quantitative 31P NMR detection of oxygen-centered and carbon-centered radical species. Bioorg Med Chem 2006; 14:4017-28. [PMID: 16504514 DOI: 10.1016/j.bmc.2006.02.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Revised: 02/02/2006] [Accepted: 02/06/2006] [Indexed: 11/23/2022]
Abstract
Quantitative 31P NMR spin trapping techniques can be used as effective tools for the detection and quantification of many free radical species. Free radicals react with a nitroxide phosphorus compound, 5-diisopropoxy-phosphoryl-5-methyl-1-pyrroline-N-oxide (DIPPMPO), to form stable radical adducts, which are suitably detected and accurately quantified using (31)P NMR in the presence of phosphorus containing internal standards. Initially, the 31P NMR signals for the radical adducts of oxygen-centered (*OH, O2*-) and carbon-centered (*CH3, *CH2OH, CH2*CH2OH) radicals were assigned. Subsequently, the quantitative reliability of the developed technique was demonstrated under a variety of experimental conditions. The 31P NMR chemical shifts for the hydroxyl and superoxide reaction adducts with DIPPMPO were found to be 25.3, 16.9, and 17.1 ppm (in phosphate buffer), respectively. The 31P NMR chemical shifts for *CH3, *CH2OH, *CH(OH)CH3, and *C(O)CH3 spin adducts were 23.1, 22.6, 27.3, and 30.2 ppm, respectively. Overall, this effort forms the foundations for a targeted understanding of the nature, identity, and mechanisms of radical activity in a variety of biomolecular processes.
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Affiliation(s)
- Dimitris S Argyropoulos
- Forest Biomaterials Laboratory, College of Natural Resources, North Carolina State University, Raleigh, NC 27695-8005, USA.
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Földes-Papp Z, Gerber G, Stösser R, Schneider G. Detection of Radicals at the Photolysis of tert-Butyl Hydroperoxide in DMSO and water. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/prac.19913330215] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Hawkins CL, Davies MJ. Generation and propagation of radical reactions on proteins. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1504:196-219. [PMID: 11245785 DOI: 10.1016/s0005-2728(00)00252-8] [Citation(s) in RCA: 503] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The oxidation of proteins by free radicals is thought to play a major role in many oxidative processes within cells and is implicated in a number of human diseases as well as ageing. This review summarises information on the formation of radicals on peptides and proteins and how radical damage may be propagated and transferred within protein structures. The emphasis of this article is primarily on the deleterious actions of radicals generated on proteins, and their mechanisms of action, rather than on enzymatic systems where radicals are deliberately formed as transient intermediates. The final section of this review examines the control of protein oxidation and how such damage might be limited by antioxidants.
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Affiliation(s)
- C L Hawkins
- Heart Research Institute, 145 Missenden Road, Camperdown, 2050, Sydney, NSW, Australia
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Headlam HA, Mortimer A, Easton CJ, Davies MJ. beta-Scission of C-3 (beta-carbon) alkoxyl radicals on peptides and proteins: a novel pathway which results in the formation of alpha-carbon radicals and the loss of amino acid side chains. Chem Res Toxicol 2000; 13:1087-95. [PMID: 11087430 DOI: 10.1021/tx0001171] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Exposure of proteins to radicals in the presence of O(2) brings about multiple changes in the target molecules. These alterations include oxidation of side chains, fragmentation, cross-linking, changes in hydrophobicity and conformation, altered susceptibility to proteolytic enzymes, and formation of new reactive groups, including hydroperoxides. These processes can result in the loss of structural or enzymatic activity. Backbone fragmentation is known to occur via a number of mechanisms, most of which involve hydrogen abstraction from the alpha-carbon site on the backbone. In this study, we demonstrate that initial attack at a side chain site, the beta-position (C-3), can give rise to formation of alpha-carbon radicals, and hence backbone cleavage, via the formation and subsequent beta-scission of C-3 alkoxyl radicals. This beta-scission reaction is rapid (k estimated to be >10(7) s(-)(1)) even with primary alkoxyl radicals derived from Ala residues, and occurs when the alkoxyl radicals are generated from a variety of precursors, including hydroperoxides and nitrate esters. These reactions release the former side chain as a reactive aldehyde or ketone; thus, Ala peptides release high yields of methanal (formaldehyde). This product has been quantified with a number of oxidized peptides and proteins, and can account for up to 64% of the initial attacking radicals with some Ala peptides. When quantified together with the hydroperoxide precursors, these species account for up to 80% of the initial radicals, confirming that this is a major process. Methanal causes cell toxicity and DNA damage and is an animal carcinogen and a genotoxic agent in human cells. Thus, the formation and subsequent reaction of alkoxyl radicals formed at the C-3 position on aliphatic amino acid side chains on peptides and proteins can give rise to both backbone fragmentation and the release of further reactive species which can cause cell toxicity and mutagenicity.
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Affiliation(s)
- H A Headlam
- The EPR Group, The Heart Research Institute, 145 Missenden Road, Camperdown, Sydney, NSW 2050, Australia
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Freyaldenhoven MA, Lehman PA, Franz TJ, Lloyd RV, Samokyszyn VM. Retinoic acid-dependent stimulation of 2,2'-azobis(2-amidinopropane)-initiated autoxidation of linoleic acid in sodium dodecyl sulfate micelles: a novel prooxidant effect of retinoic acid. Chem Res Toxicol 1998; 11:102-10. [PMID: 9511901 DOI: 10.1021/tx970044u] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
(E)-Retinoic acid (RA) was shown to stimulate the rate of 2,2'-azobis(2-amidinopropane) (AAPH)-initiated autoxidation of linoleic acid (18:2) in sodium dodecyl sulfate (SDS) micelles. RA-dependent stimulation of 18:2 autoxidation was characterized by enhanced rates of dioxygen uptake which were linear with retinoid concentration. In contrast, 5,6-epoxy-RA, a major oxidation product of RA, failed to affect the rate of dioxygen consumption at all concentrations tested. RA was also shown to stimulate peroxyl radical-dependent oxidation of styrene to the corresponding oxirane when styrene was included in the micellar system as a molecular probe. Furthermore, unequivocal evidence of RA-dependent stimulation of 18:2 autoxidation was obtained by relative quantitation of 13-hydroxy-(9Z, 11E)-octadecadienoic acid (13-HODE) plus 9-hydroxy-(10E,12Z)-octadecadienoic acid (9-HODE) production. In addition, enhanced carbon-centered radical formation was demonstrated in the presence of RA by EPR spectroscopy using alpha-(4-pyridyl 1-oxide)-N-tert-butylnitrone (4-POBN) as a spin trap. Analysis and quantitation of RA oxidation products indicated that RA was oxidized to one primary product, 5,6-epoxy-RA, which was identified on the basis of cochromatography with synthetic standard (in a reverse-phase HPLC system), electronic absorption spectroscopy, and positive chemical ionization mass spectrometry of the corresponding methyl ester. Other minor oxidation products were also detected but not characterized. In contrast, reaction mixtures devoid of 18:2 failed to demonstrate significant retinoid oxidation. Mechanisms are proposed to account for the prooxidant effects of RA in this system.
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Affiliation(s)
- M A Freyaldenhoven
- Department of Pharmacology & Toxicology, University of Arkansas for Medical Sciences, Little Rock 72205, USA
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Iannone A, Tomasi A, Canfield LM. Generation of N-tert-butyl-α-phenylnitrone radical adducts in iron breakdown of tert-butyl-hydroperoxide. RESEARCH ON CHEMICAL INTERMEDIATES 1996. [DOI: 10.1163/156856796x00674] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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The effect of inclusion in?-cyclodextrin on the chemistry of peroxides: Reactions of radicals with?-cyclodextrin. ACTA ACUST UNITED AC 1995. [DOI: 10.1007/bf00707888] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Some chemical and biochemical constraints of oxidative stress in living cells* *This chapter is dedicated to René Buvet († November 26, 1992) who led me to the astonishing world of oxygen biochemistry. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/s0167-7306(08)60438-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Chamulitrat W, Hughes MF, Eling TE, Mason RP. Superoxide and peroxyl radical generation from the reduction of polyunsaturated fatty acid hydroperoxides by soybean lipoxygenase. Arch Biochem Biophys 1991; 290:153-9. [PMID: 1654862 DOI: 10.1016/0003-9861(91)90601-e] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Soybean lipoxygenase is shown to catalyze the breakdown of polyunsaturated fatty acid hydroperoxides to produce superoxide radical anion as detected by spin trapping with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). In addition to the DMPO/superoxide radical adduct, the adducts of peroxyl, acyl, carbon-centered, and hydroxyl radicals were identified in incubations containing linoleic acid and lipoxygenase. These DMPO radical adducts were observed just prior to the system becoming anaerobic. Only a carbon-centered radical adduct was observed under anaerobic conditions. The superoxide radical production required the presence of fatty acid substrates, fatty acid hydroperoxides, active lipoxygenase, and molecular oxygen. Superoxide radical production was inhibited when nordihydroguaiaretic acid, butylated hydroxytoluene, or butylated hydroxyanisole was added to the incubation mixtures. We propose that polyunsaturated fatty acid hydroperoxides are reduced to form alkoxyl radicals and that after an intramolecular rearrangement, the resulting hydroxyalkyl radical reacts with oxygen, forming a peroxyl radical which subsequently eliminates superoxide radical anion.
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Affiliation(s)
- W Chamulitrat
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709
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Mark G, Schuchmann MN, Schuchmann HP, von Sonntag C. The photolysis of potassium peroxodisulphate in aqueous solution in the presence of tert-butanol: a simple actinometer for 254 nm radiation. J Photochem Photobiol A Chem 1990. [DOI: 10.1016/1010-6030(90)80028-v] [Citation(s) in RCA: 127] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Chamulitrat W, Mason RP. Alkyl free radicals from the beta-scission of fatty acid alkoxyl radicals as detected by spin trapping in a lipoxygenase system. Arch Biochem Biophys 1990; 282:65-9. [PMID: 2171436 DOI: 10.1016/0003-9861(90)90087-f] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
2-Methyl-2-nitrosopropane (tNB)-radical adducts from incubation mixtures of fatty acids and soybean lipoxygenase in borate buffer (pH 9.0) were measured by electron paramagnetic resonance (EPR). In addition to the previously reported six-line signal of secondary carbon-centered radicals (RCHR'), a weak signal submerged in the baseline was detected after the peroxidation phase was finished. We propose that this radical is a decomposition product formed via beta-scission of fatty acid alkoxyl radicals. EPR spectra of tNB-radical adducts formed in mixtures of either linoleic acid, arachidonic acid, or 15-hydroperoxyeicosatetraenoic acid with lipoxygenase exhibited hyperfine structure characteristic of tNB/.CH2CH2-R with hyperfine coupling constants: aN = 17.1 G; aH beta = 11.2 G (2H); and aH gamma = 0.6 G (2H). In the case of linolenic acid, this radical tNB/.CH=CH-R' with hyperfine coupling constants: aN = 17.1 G; aH beta = 10.9 G (2H); aH gamma = 1.1 G; and aH delta = 0.5 G. In accord with the decomposition scheme of hydroperoxides derived from unsaturated fatty acids, the radical adducts tNB/.CH2CH2-R and tNB/.CH2-CH=CH-R' were assigned as the pentyl and 2-pentenyl radicals, respectively.
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Affiliation(s)
- W Chamulitrat
- National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
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Chamulitrat W, Takahashi N, Mason RP. Peroxyl, alkoxyl, and carbon-centered radical formation from organic hydroperoxides by chloroperoxidase. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)83127-1] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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