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Saad-El-Din AA, El-Tanahy ZH, El-Sayed SN, Anees LM, Farroh HA. Study of electron spin resonance and viscosity for hemoglobin polymer after arsenic trioxide and gamma irradiation treatment. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2019. [DOI: 10.1016/j.jrras.2014.07.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Aisha A. Saad-El-Din
- Biophys., Lab. Rad. Phys. Dep. National Center of Radiation Research and Technology (NCRRT), AEA, P.O. Box 29, Madinat Nasr, Cairo, Egypt
| | - Zinab H. El-Tanahy
- Nucl. Phys. Dep. Faculty of Science, Al-Azhar University, Girls branch, Cairo, Egypt
| | - Suzan N. El-Sayed
- Solid Stat. Phys. Dep. Faculty of Science, Al-Azhar University, Girls branch, Cairo, Egypt
| | - Laila M. Anees
- Health Res. Dep. National Center of Radiation Research and Technology (NCRRT), AEA, P.O. Box 29, Madinat Nasr, Cairo, Egypt
| | - Hoda A. Farroh
- Health Res. Dep. National Center of Radiation Research and Technology (NCRRT), AEA, P.O. Box 29, Madinat Nasr, Cairo, Egypt
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2
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Li G, Liu X, An T, Wong PK, Zhao H. A novel method developed for estimating mineralization efficiencies and its application in PC and PEC degradations of large molecule biological compounds with unknown chemical formula. WATER RESEARCH 2016; 95:150-158. [PMID: 26994335 DOI: 10.1016/j.watres.2016.02.066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 02/28/2016] [Accepted: 02/29/2016] [Indexed: 06/05/2023]
Abstract
A new method to estimate the photocatalytic (PC) and photoelectrocatalytic (PEC) mineralization efficiencies of large molecule biological compounds with unknown chemical formula in water was firstly developed and experimentally validated. The method employed chemical oxidation under the standard dichromate chemical oxygen demand (COD) conditions to obtain QCOD values of model compounds with unknown chemical formula. The measured QCOD values were used as the reference to replace QCOD values of model compounds for calculation of the mineralization efficiencies (in %) by assuming the obtained QCOD values are the measure of the theoretical charge required for the complete mineralization of organic pollutants. Total organic carbon (TOC) was also employed as a reference to confirm the mineralization capacity of dichromate chemical oxidation. The developed method was applied to determine the degradation extent of model compounds, such as bovine serum albumin (BSA), lecithin and bacterial DNA, by PC and PEC. Incomplete PC mineralization of all large molecule biological compounds was observed, especially for BSA. But the introduction of electrochemical technique into a PC oxidation process could profoundly improve the mineralization efficiencies of model compounds. PEC mineralization efficiencies of bacterial DNA was the highest, while that of lecithin was the lowest. Overall, PEC degradation method was found to be much effective than PC method for all large molecule biological compounds investigated, with PEC/PC mineralization ratios followed an order of BSA > lecithin > DNA.
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Affiliation(s)
- Guiying Li
- Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China; Centre for Clean Environment and Energy, Gold Coast Campus, Griffith University, Queensland, 4222, Australia
| | - Xiaolu Liu
- Centre for Clean Environment and Energy, Gold Coast Campus, Griffith University, Queensland, 4222, Australia; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Taicheng An
- Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
| | - Po Keung Wong
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Huijun Zhao
- Centre for Clean Environment and Energy, Gold Coast Campus, Griffith University, Queensland, 4222, Australia.
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3
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Rodacka A. The effect of radiation-induced reactive oxygen species (ROS) on the structural and functional properties of yeast alcohol dehydrogenase (YADH). Int J Radiat Biol 2015; 92:11-23. [DOI: 10.3109/09553002.2015.1106022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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4
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Abdanan Mehdizadeh S, Minaei S, Karimi Torshizi MA, Mohajerani E. Effect of UV irradiation, sample thickness and storage temperature on storability, bacterial activity and functional properties of liquid egg. JOURNAL OF FOOD SCIENCE AND TECHNOLOGY 2015; 52:4414-22. [PMID: 26139907 PMCID: PMC4486587 DOI: 10.1007/s13197-014-1509-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 08/13/2013] [Accepted: 08/25/2013] [Indexed: 11/29/2022]
Abstract
Effect of sample thickness, ultraviolet irradiation and storage temperature on bacterial activity, storability and functional properties (foamability and stability) of liquid egg were investigated. Eggs were contaminated with prepared Salmonella suspension 108/mL. Separated albumen and yolk samples were poured in three thicknesses (1, 2 and 3 mm) and irradiated at 3, 5 10, 15 min with ultraviolet radiation and were stored at 5, 15, 25, 37 °C for up to 8 days. Observations indicated that all ultraviolet irradiation times, reduced the total count of Salmonella bacteria in egg samples. Although, functional properties were improved, protein oxidation in both albumen and yolk increased. After the first 2 days of storage, total counts of Salmonella and protein oxidation of eggs decreased solely in the 5 °C treatment. It is concluded that irradiation treatment can be used to decrease bacterial contamination of liquid egg albeit not below the safe level for raw consumption. Furthermore, the best irradiation times to improve foam ability and stability were 10 and 5 min, respectively.
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Affiliation(s)
- S. Abdanan Mehdizadeh
- />Department of Agricultural Machinery, College of Agricultural Engineering, Ramin Khuzestan University of Agriculture and Natural Resources, Mollasani, Ahvaz, Khuzestan Iran
| | - S. Minaei
- />Faculty of Agriculture, Department of Agricultural Machinery Engineering, Tarbiat Modares University, Tehran, Iran
| | - M. A. Karimi Torshizi
- />Faculty of Agriculture, Department of Poultry Science, Tarbiat Modares University, Tehran, Iran
| | - E. Mohajerani
- />Department of Physics, Shahid Beheshti University, Tehran, Iran
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5
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Wigginton KR, Menin L, Sigstam T, Gannon G, Cascella M, Hamidane HB, Tsybin YO, Waridel P, Kohn T. UV radiation induces genome-mediated, site-specific cleavage in viral proteins. Chembiochem 2012; 13:837-45. [PMID: 22416020 DOI: 10.1002/cbic.201100601] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Indexed: 11/07/2022]
Abstract
Much research has been dedicated to understanding the molecular basis of UV damage to biomolecules, yet many questions remain regarding the specific pathways involved. Here we describe a genome-mediated mechanism that causes site-specific virus protein cleavage upon UV irradiation. Bacteriophage MS2 was disinfected with 254 nm UV, and protein damage was characterized with ESI- and MALDI-based FT-ICR, Orbitrap, and TOF mass spectroscopy. Top-down mass spectrometry of the products identified the backbone cleavage site as Cys46-Ser47 in the virus capsid protein, a location of viral genome-protein interaction. The presence of viral RNA was essential to inducing backbone cleavage. The similar bacteriophage GA did not exhibit site-specific protein cleavage. Based on the major protein fragments identified by accurate mass analysis, a cleavage mechanism is proposed by radical formation. The mechanism involves initial oxidation of the Cys46 side chain followed by hydrogen atom abstraction from Ser47 C(α). Computational protein QM/MM studies confirmed the initial steps of the radical mechanism. Collectively, this study describes a rare incidence of genome-induced protein cleavage without the addition of sensitizers.
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Affiliation(s)
- Krista Rule Wigginton
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
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6
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Sterilization and protection of protein in combinations of Camellia sinensis green tea extract and gamma irradiation. Int J Biol Macromol 2011; 48:452-8. [DOI: 10.1016/j.ijbiomac.2011.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 12/18/2010] [Accepted: 01/04/2011] [Indexed: 01/16/2023]
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7
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Frengova GI, Beshkova DM. Carotenoids from Rhodotorula and Phaffia: yeasts of biotechnological importance. J Ind Microbiol Biotechnol 2008; 36:163-80. [PMID: 18982370 DOI: 10.1007/s10295-008-0492-9] [Citation(s) in RCA: 168] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Accepted: 10/14/2008] [Indexed: 10/21/2022]
Abstract
Carotenoids represent a group of valuable molecules for the pharmaceutical, chemical, food and feed industries, not only because they can act as vitamin A precursors, but also for their coloring, antioxidant and possible tumor-inhibiting activity. Animals cannot synthesize carotenoids, and these pigments must therefore be added to the feeds of farmed species. The synthesis of different natural commercially important carotenoids (beta-carotene, torulene, torularhodin and astaxanthin) by several yeast species belonging to the genera Rhodotorula and Phaffia has led to consider these microorganisms as a potential pigment sources. In this review, we discuss the biosynthesis, factors affecting carotenogenesis in Rhodotorula and Phaffia strains, strategies for improving the production properties of the strains and directions for potential utility of carotenoid-synthesizing yeast as a alternative source of natural carotenoid pigments.
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Affiliation(s)
- Ginka I Frengova
- Laboratory of Applied Microbiology, Institute of Microbiology, Bulgarian Academy of Sciences, 26 Maritza Blvd., 4002, Plovdiv, Bulgaria.
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8
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Jones BJ, Vergne MJ, Bunk DM, Locascio LE, Hayes MA. Cleavage of Peptides and Proteins Using Light-Generated Radicals from Titanium Dioxide. Anal Chem 2007; 79:1327-32. [PMID: 17297930 DOI: 10.1021/ac0613737] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Protein identification and characterization often requires cleavage into distinct fragments. Current methods require proteolytic enzymes or chemical agents and typically a second reagent to discontinue cleavage. We have developed a selective cleavage process for peptides and proteins using light-generated radicals from titanium dioxide. The hydroxyl radicals, produced at the TiO(2) surface using UV light, are present for only hundreds of microseconds and are confined to a defined reagent zone. Peptides and proteins can be moved past the "reagent zone", and cleavage is tunable through residence time, illumination time, and intensity. Using this method, products are observed consistent with cleavage at proline residues. These initial experiments indicate the method is rapid, specific, and reproducible. In certain configurations, cleavage products are produced in less than 10 s. Reproducible product patterns consistent with cleavage of the peptide bond at proline for angiotensin I, Lys-bradykinin, and myoglobin are demonstrated using capillary electrophoresis. Mass characterization of fragments produced in the cleavage of angiotensin I was obtained using liquid chromatography-mass spectrometry. In addition to the evidence supporting cleavage at proline, enkephalin and peptide A-779, two peptides that do not contain proline, showed no evidence of cleavage under the same conditions.
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9
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Nazzaro F, Fratianni F, Picariello G, Coppola R, Reale A, Luccia AD. Evaluation of gamma rays influence on some biochemical and microbiological aspects in black truffles. Food Chem 2007. [DOI: 10.1016/j.foodchem.2006.07.067] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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10
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Lee S, Sun N, Jang J, An G, Won M, Song K. Characterization of Phaffia rhodozyma 3A 4-8 Generated by Low-dose γ-irradiation. J Food Sci 2006. [DOI: 10.1111/j.1365-2621.2004.tb09939.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Gaber MH. Effect of gamma-irradiation on the molecular properties of bovine serum albumin. J Biosci Bioeng 2005; 100:203-6. [PMID: 16198265 DOI: 10.1263/jbb.100.203] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2004] [Accepted: 04/28/2005] [Indexed: 11/17/2022]
Abstract
To investigate the effect of oxygen radicals on the molecular properties of bovine serum albumin (BSA), the secondary and tertiary structures, molecular weight and optical anisotropy of BSA were examined after the irradiation of the protein at various doses. gamma-Irradiation of the protein solution caused the disruption of the ordered structure of protein molecules as well as degradation, cross-linking and aggregation of polypeptide chains. Fluorescence spectroscopy indicated that irradiation quenched the emission intensity excited at 280 nm. Fourier transform infrared spectroscopy (FTIR) indicated that irradiation caused transformation from beta-turns into beta-sheets. A light scattering study showed that increasing the radiation dose decreased the molecular weight of the protein. Optical anisotropy data showed that radiation changed the ordered structure of the protein. Ultraviolet absorption spectroscopy indicated that fragmentation and aggregation might occur in response to radiation exposure.
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Affiliation(s)
- Mohamed H Gaber
- Biophysics Department, Faculty of Science, Cairo University, Giza, Egypt.
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12
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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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13
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Sun N, Lee S, Song KB. Characterization of a carotenoid-hyperproducing yeast mutant isolated by low-dose gamma irradiation. Int J Food Microbiol 2004; 94:263-7. [PMID: 15246237 DOI: 10.1016/s0168-1605(03)00311-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2002] [Revised: 03/20/2003] [Accepted: 04/22/2003] [Indexed: 11/30/2022]
Abstract
To isolate a carotenoid-hyperproducing yeast, Phaffia rhodozyma was treated by low-dose gamma irradiation below 10 kGy. Through repeated rounds of gamma irradiation and visual screening, a mutant 3A4-8 was isolated. It produced 3.3 mg of carotenoid per gram of yeast, 50% higher carotenoid content than that of the unirradiated strain. Glucose and peptone were the most suitable carbon and nitrogen sources for production of carotenoid based on the growth experiment of the mutant under various carbon and nitrogen sources. This result suggests that low-dose gamma irradiation could be used as a means of mutagenesis for isolation of a carotenoid-hyperproducing strain of P. rhodozyma because only the carotenoid-hyperproducing yeast survives gamma irradiation by scavenging oxygen radicals generated by radiolysis of water.
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Affiliation(s)
- Namkyu Sun
- Department of Food Science and Technology, College of Agricultural and Life Sciences, Chungnam National University, Daejeon 305-764, South Korea
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14
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15
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Lee Y, Song KB. Effect of gamma-irradiation on the molecular properties of myoglobin. JOURNAL OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2002; 35:590-4. [PMID: 12470593 DOI: 10.5483/bmbrep.2002.35.6.590] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To elucidate the effect of gamma-irradiation on the molecular properties of myoglobin, the secondary and tertiary structures, as well as the molecular weight size of the protein, were examined after irradiation at various irradiation doses. Gamma-irradiation of myoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, crosslinking, and aggregation of the polypeptide chains. A SDSPAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation, due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid protected against the degradation and aggregation of proteins by scavenging oxygen radicals that are produced by irradiation. A circular dichroism study showed that an increase of the irradiation decreased the alpha-helical content of myoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation increased the emission intensity that was excited at 280 nm.
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Affiliation(s)
- Yongwoo Lee
- Department of Food Science and Technology, College of Agriculture and Life Sciences, Chungnam National University, Taejon 305-764, Korea
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16
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Song KB, Lee S, Lee S. Effect of Gamma-Irradiation on the Molecular Properties of Blood Plasma Proteins. Prev Nutr Food Sci 2002. [DOI: 10.3746/jfn.2002.7.2.184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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17
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Moon S, Song KB. Effect of γ-irradiation on the molecular properties of ovalbumin and ovomucoid and protection by ascorbic acid. Food Chem 2001. [DOI: 10.1016/s0308-8146(01)00166-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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18
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Siddique MS, Eddeb F, Mantle D, Mendelow AD. Extracts of Ginkgo biloba and Panax ginseng protect brain proteins from free radical induced oxidative damage in vitro. ACTA NEUROCHIRURGICA. SUPPLEMENT 2001; 76:87-90. [PMID: 11450098 DOI: 10.1007/978-3-7091-6346-7_18] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Oxidative damage to normal human brain tissue was induced following exposure to hydroxyl (OH.) or superoxide (O2-.) free radical species generated by CO60 irradiation in vitro. Both enzymic and cytoskeletal proteins showed substantial (dose dependent) oxidative damage following exposure to OH. or O2-., as quantified by SDS-polyacrylamide gel electrophoretic analysis. Extracts of Ginkgo biloba or Panax ginseng showed a remarkable capacity to protect brain tissue proteins from oxidative damage in vitro, even at extreme (2000 kRads) dosage levels of OH. or O2-.. We suggest, therefore, that the beneficial effect of these plant extracts in preventing brain tissue damage in vivo (e.g. following ischemia-reperfusion) may result from their action in protecting brain proteins from oxidative damage, in addition to their previously reported capacity to reduce free radical induced lipid peroxidation.
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Affiliation(s)
- M S Siddique
- Department of Neurosurgery, Regional Neurosciences Centre, Newcastle General Hospital, UK
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19
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Radiation chemistry of proteins. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0167-6881(01)80022-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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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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21
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Mantle D, Eddeb F, Areni K, Snowden C, Mendelow AD. Comparative antioxidant potential of anaesthetics and perioperative drugs in vitro. Clin Chim Acta 2000; 301:41-53. [PMID: 11020461 DOI: 10.1016/s0009-8981(00)00315-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have investigated the comparative antioxidant capacity of a range of anaesthetics (inhaled and intravenous) and perioperative neurosurgical drugs (at clinically relevant concentrations) using different radical species and assay methods in vitro. The highest levels of antioxidant activity against the ABTS(.+) radical were obtained with propofol (100 mmol/LTE) and dopamine (1080 mmol/LTE), respectively. However, only dopamine (12 mmol/l) showed antioxidant activity in protecting proteins in normal brain tissue from oxidative damage (assessed via SDS-PAGE analysis) induced by OH(.) or O(2)(-.) generated radiolytically in vitro. Neither dopamine nor propofol showed antioxidant activity against O(2)(-.) generated chemically via reaction between xanthine and xanthine oxidase in vitro. From these data, together with data on the relative antioxidant properties of anaesthetics/drugs obtained by other research groups which we have reviewed, we conclude that the apparent antioxidant activity of a given compound may depend entirely on the free radical species and/or the method of generation or assay employed. Finally, we suggest that on the basis of data obtained showing protection of brain proteins from oxidative damage induced by OH(.), or O(2)(-.) in vitro, further investigation into the in vivo antioxidant therapeutic potential of dopamine (or its analogues) on neurosurgical patients may be warranted.
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Affiliation(s)
- D Mantle
- Department of Neurochemistry, Regional Neurosciences Centre, Newcastle General Hospital, New Castle-upon-Tyne NE4 6BE, UK
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Maleknia SD, Brenowitz M, Chance MR. Millisecond radiolytic modification of peptides by synchrotron X-rays identified by mass spectrometry. Anal Chem 1999; 71:3965-73. [PMID: 10500483 DOI: 10.1021/ac990500e] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Radiolysis of peptide and protein solutions with high-energy X-ray beams induces stable, covalent modifications of amino acid residues that are useful for synchrotron protein footprinting. A series of 5-14 amino acid residue peptides of varied sequences were selected to study their synchrotron radiolysis chemistry. Radiolyzed peptide products were detected within 10 ms of exposure to a white light synchrotron X-ray beam. Mass spectrometry techniques were used to characterize radiolytic modification to amino acids cysteine (Cys), methionine (Met), phenylalanine (Phe), tyrosine (Tyr), tryptophan (Trp), proline (Pro), histidine (His), and leucine (Leu). A reactivity order of Cys, Met >> Phe, Tyr, > Trp > Pro > His, Leu was determined under aerobic reaction conditions from MS/MS analysis of the radiolyzed peptide products. Radiolysis of peptides in 18O-labeled water under aerobic conditions revealed that oxygenated radical species from air and water both contribute to the modification of amino acid side chains. Cysteine and methionine side chains reacted with hydroxyl radicals generated from radiolysis of water as well as molecular oxygen. Phenylalanine and tyrosine residues were modified predominantly by hydroxyl radicals, and the source of modification of proline was exclusively through molecular oxygen.
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Affiliation(s)
- S D Maleknia
- Albert Einstein Center for Synchrotron BioSciences, Department of Physiology & Biophysics, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York 10461, USA.
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23
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Yang YCJ, Song KB. Effect of ascorbic acid and protein concentration on the molecular weight profile of bovine serum albumin and β-lactoglobulin by γ-irradiation. Food Res Int 1999. [DOI: 10.1016/s0963-9969(99)00127-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Rauk A, Yu D, Taylor J, Shustov GV, Block DA, Armstrong DA. Effects of structure on alpha C-H bond enthalpies of amino acid residues: relevance to H transfers in enzyme mechanisms and in protein oxidation. Biochemistry 1999; 38:9089-96. [PMID: 10413483 DOI: 10.1021/bi990249x] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The bond dissociation enthalpies (BDE) of all of the amino acid residues, modeled by HC(O)NHCH(R)C(O)NH(2) (PH(res)), were determined at the B3LYP/6-31G//B3LYP/6-31G level, coupled with isodesmic reactions. The results for neutral side chains with phi, psi angles approximately 180 degrees, approximately 180 degrees in ascending order, to an expected accuracy of +/-10 kJ mol(-)(1), are Asn 326; cystine 330; Asp 332; Gln 334; Trp 337; Arg 340; Lys 340; Met 343; His 344; Phe 344; Tyr 344; Leu 344; Ala 345; Cys 346; Ser 349; Gly 350; Ile 351; Val 352; Glu 354; Thr 357; Pro-cis 358; Pro-trans 369. BDEs calculated at the ROMP2/6-31G//B3LYP/6-31G level exhibit the same trends but are approximately 7 kJ mol(-)(1) higher. All BDEs are smaller than those of typical secondary or tertiary C-H bonds due to the phenomenon of captodative stabilization. The stabilization is reduced by changes in the phi,psi angles. As a result the BDEs increase by about 10 kJ mol(-)(1) in beta-sheet and 40 kJ mol(-)(1) in alpha-helical environments, respectively. In effect the alpha C-H BDEs can be "tuned" from about 345 to 400 kJ mol(-)(1) by adjusting the local environment. Some very significant effects of this are seen in the current literature on H-transfer processes in enzyme mechanisms and in oxidative damage to proteins. These observations are discussed in terms of the findings of the present study.
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Affiliation(s)
- A Rauk
- Department of Chemistry, University of Calgary, Alberta, Canada
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25
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Abstract
We have studied the effects of the interaction of radiation generated human serum albumin radicals (HSA*) with human hemoglobin molecules (Hb). Diluted Hb aqueous solutions were irradiated under N2O or argon without HSA and in the presence of HSA. Analysis of Hb absorbance spectra in the visible range, cross-linking of HSA* radicals with Hb molecules and functional properties of Hb were investigated. The degree of Hb destruction estimated on the basis of changes in the absorption spectra indicated that the effectiveness of HSA* radicals generated under N2O for Hb destruction was approximately equal to that of *OH radicals. In this case mainly *OH radicals formed the secondary HSA* radicals. However, during the irradiation Hb + HSA under argon the presence of equivalent amounts of oxidizing and reducing products of water radiolysis lowers the degree of Hb destruction. Some reactions of HSA* radicals with Hb molecules lead to the formation of covalent bonds between the molecules of both proteins. The following types of hybrids could be distinguished: Hb monomer-HSA, Hb dimer-HSA and higher aggregates. Structural changes of Hb by HSA* radicals were reflected by alterations in the oxygen affinity (increase) and cooperativity (decrease) of Hb. The results obtained indicate that in the experimental systems studied, the HSA* radical reactions with Hb molecules are favoured over recombination reactions of HSA* radicals. On this basis one can suggest that in the studied systems Hb plays the role of an acceptor of radical energy located on HSA.
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Affiliation(s)
- M Puchała
- Department of Molecular Biophysics, University of Lódź, Poland
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26
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Finley EL, Dillon J, Crouch RK, Schey KL. Radiolysis-Induced Oxidation of Bovine α-Crystallin. Photochem Photobiol 1998. [DOI: 10.1111/j.1751-1097.1998.tb03245.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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27
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Traverso N, Menini S, Cottalasso D, Odetti P, Marinari UM, Pronzato MA. Mutual interaction between glycation and oxidation during non-enzymatic protein modification. BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1336:409-18. [PMID: 9367168 DOI: 10.1016/s0304-4165(97)00052-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Aging pathogenesis involves non-enzymatic modifications of proteins; protein oxidation, glycation and their interactions have aroused a particular interest. Possible interrelations between oxidation and glycation have been evaluated in vitro: bovine serum albumin was oxidized by gamma-irradiation and then exposed to in vitro glycation. Fluorescence modifications induced by radiolytic oxidation and glycation were similar and tended to be additive. Both non-enzymatic processes provoked a loss of free sulfhydryl groups and a strong increment of protein carbonyl content: this supports that glycation can act through oxidative mechanisms. The observed rearrangement of amino groups after irradiation could predispose proteins to glycation attacks. Protein peroxides generated during irradiation appear able to give birth to further protein modifications leading to the generation of carbonyl groups and to interact with monosaccharides, probably stimulating their autoxidation and in turn glycative protein damage. Glycation increases the oxidation-mediated structural damage revealed by SDS-PAGE. Therefore our data support the hypothesis of mutual enhancement between oxidation and glycation of proteins and suggest possible molecular mechanisms of interactions.
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Affiliation(s)
- N Traverso
- Institute of General Pathology, Genova, Italy.
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28
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Filali-Mouhim A, Audette M, St-Louis M, Thauvette L, Denoroy L, Penin F, Chen X, Rouleau N, Le Caer JP, Rossier J, Potier M, Le Maire M. Lysozyme fragmentation induced by gamma-radiolysis. Int J Radiat Biol 1997; 72:63-70. [PMID: 9246195 DOI: 10.1080/095530097143545] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Irradiation of lysozyme in frozen states in the absence of oxygen induces specific fragmentation at defined sites along the backbone chain. This paper localizes radio-fragmentation sites by two methods. First, N-terminal sequencing of radiolysis fragments after separation by SDS-polyacrylamide gel electrophoresis and estimation of their molecular masses. Secondly, after purification of radiolysis fragments by reverse phase-HPLC and determination of their molecular mass by electro-spray-ionization mass-spectrometric analysis, combined to N-terminal sequencing and total amino acid analysis. Evidence for the breakage of the peptide bond itself (CO-NH) is given, with radio-fragmentation sites mostly found at the surface of irradiated lysozyme in solvent exposed loops and turns.
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Affiliation(s)
- A Filali-Mouhim
- Hôpital Sainte-Justine, Département de Pédiatrie, Université de Montréal, Québec, Canada
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29
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Dean RT, Fu S, Stocker R, Davies MJ. Biochemistry and pathology of radical-mediated protein oxidation. Biochem J 1997; 324 ( Pt 1):1-18. [PMID: 9164834 PMCID: PMC1218394 DOI: 10.1042/bj3240001] [Citation(s) in RCA: 1128] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Radical-mediated damage to proteins may be initiated by electron leakage, metal-ion-dependent reactions and autoxidation of lipids and sugars. The consequent protein oxidation is O2-dependent, and involves several propagating radicals, notably alkoxyl radicals. Its products include several categories of reactive species, and a range of stable products whose chemistry is currently being elucidated. Among the reactive products, protein hydroperoxides can generate further radical fluxes on reaction with transition-metal ions; protein-bound reductants (notably dopa) can reduce transition-metal ions and thereby facilitate their reaction with hydroperoxides; and aldehydes may participate in Schiff-base formation and other reactions. Cells can detoxify some of the reactive species, e.g. by reducing protein hydroperoxides to unreactive hydroxides. Oxidized proteins are often functionally inactive and their unfolding is associated with enhanced susceptibility to proteinases. Thus cells can generally remove oxidized proteins by proteolysis. However, certain oxidized proteins are poorly handled by cells, and together with possible alterations in the rate of production of oxidized proteins, this may contribute to the observed accumulation and damaging actions of oxidized proteins during aging and in pathologies such as diabetes, atherosclerosis and neurodegenerative diseases. Protein oxidation may also sometimes play controlling roles in cellular remodelling and cell growth. Proteins are also key targets in defensive cytolysis and in inflammatory self-damage. The possibility of selective protection against protein oxidation (antioxidation) is raised.
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Affiliation(s)
- R T Dean
- Cell Biology Unit, The Heart Research Institute, 145-147 Missenden Road, Camperdown, Sydney, NSW 2050, Australia
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30
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Puchała M, Schuessler H. Oxygen effect in the radiolysis of proteins. IV. Myoglobin. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1995; 46:326-32. [PMID: 8537187 DOI: 10.1111/j.1399-3011.1995.tb00605.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Radiolysis of myoglobin was carried out under air and under nitrogen in phosphate buffer at pH 5 and 7. The radiation products were separated by SDS-polyacrylamide gel electrophoresis and by HPL gel chromatography with guanidine.HCl. Under nitrogen the main reaction is the aggregation caused by covalent cross-links. Under air the radiolysis leads to peptide chain scission, which is not a random process, but produces specific protein fragments. The estimated molecular weights of these fragments gave further support to the assumption that the aminoacyl-proline peptide group is the preferential breaking site. In contrast to haemoglobin, myoglobin showed nearly no radiation-induced fragmentation under nitrogen.
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Affiliation(s)
- M Puchała
- Department of Molecular Biophysics, University of Lódź, Poland
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31
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Bhattacharya D, Saha A, Mandal PC. Radiation-induced inactivation of flavocytochrome b2 in dilute aqueous solution. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1250:1-8. [PMID: 7612647 DOI: 10.1016/0167-4838(95)00040-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Effect of gamma radiation on flavocytochrome b2 in dilute aqueous solution was studied. A study of the effect of the radiolytically produced inorganic free-radical anions such as I2.-, Br2.- and (SCN)2.- on the enzyme activity indicates the involvement of cysteine and tyrosine residues in the catalytic activity of flavocytochrome b2. The changes in kinetic parameters, i.e., Michaelis-Menten constant Km and maximal velocity Vmax, due to irradiation under different conditions suggest that radiation induced enzyme inactivation is the result of destruction of active-site residues as well as modification of the substrate binding site. Fluorescence studies of unirradiated and irradiated enzyme reveal that FMN (flavin mononucleotide) is inaccessible to water radicals.
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Affiliation(s)
- D Bhattacharya
- Nuclear Chemistry Division, Saha Institute of Nuclear Physics, Calcutta, India
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32
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Saha A, Mandal P, Bhattacharyya S. Radiation-induced inactivation of enzymes—A review. Radiat Phys Chem Oxf Engl 1993 1995. [DOI: 10.1016/0969-806x(94)00130-c] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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