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Abstract
Endogenous photosensitizers play a critical role in both beneficial and harmful light-induced transformations in biological systems. Understanding their mode of action is essential for advancing fields such as photomedicine, photoredox catalysis, environmental science, and the development of sun care products. This review offers a comprehensive analysis of endogenous photosensitizers in human skin, investigating the connections between their electronic excitation and the subsequent activation or damage of organic biomolecules. We gather the physicochemical and photochemical properties of key endogenous photosensitizers and examine the relationships between their chemical reactivity, location within the skin, and the primary biochemical events following solar radiation exposure, along with their influence on skin physiology and pathology. An important take-home message of this review is that photosensitization allows visible light and UV-A radiation to have large effects on skin. The analysis presented here unveils potential causes for the continuous increase in global skin cancer cases and emphasizes the limitations of current sun protection approaches.
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Affiliation(s)
- Erick L Bastos
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, 05508-000 São Paulo, São Paulo, Brazil
| | - Frank H Quina
- Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, 05508-000 São Paulo, São Paulo, Brazil
- Department of Chemical Engineering, Polytechnic School, University of São Paulo, 05508-000 São Paulo, São Paulo, Brazil
| | - Maurício S Baptista
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, 05508-000 São Paulo, São Paulo, Brazil
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2
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Vogt LI, Cotelesage JJH, Dolgova NV, Boyes C, Qureshi M, Sokaras D, Sharifi S, George SJ, Pickering IJ, George GN. Sulfur X-ray Absorption and Emission Spectroscopy of Organic Sulfones. J Phys Chem A 2023; 127:3692-3704. [PMID: 36912654 DOI: 10.1021/acs.jpca.2c08647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
Abstract
The sulfones are a widespread group of organo-sulfur compounds, which contain the sulfonyl SO2 group attached to two carbons and have a formal sulfur oxidation state of +2. We have examined the sulfur K near-edge X-ray absorption spectroscopy (XAS) of a range of different sulfones and find substantial spectroscopic variability depending upon the nature of the coordination to the sulfonyl group. We have also examined the sulfur Kβ X-ray emission spectroscopy (XES) of selected representative sulfones. Density functional theory simulations show satisfactory reproduction of both absorption and emission spectra while enabling assignment of the various transitions comprising the spectra. The correspondence between observed and simulated spectra shows promise for ab initio prediction of sulfur X-ray absorption and emission spectra of sulfones of any substituent. The absorption spectra and, to a lesser extent, the emission spectra are sensitive to the nature of the organic groups bound to the sulfonyl (SO2) moiety, clearly showing the potential of X-ray spectroscopy as an in situ probe of sulfone chemistry.
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Affiliation(s)
- Linda I Vogt
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Julien J H Cotelesage
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Natalia V Dolgova
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Curtis Boyes
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Muhammad Qureshi
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, United States
| | - Dimosthenis Sokaras
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, United States
| | - Samin Sharifi
- Chevron Energy Technology Company, Richmond, California 94802, United States
| | - Simon J George
- Simon Scientific, P.O. Box 71024, Richmond, California 94807, United States
| | - Ingrid J Pickering
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada.,Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9, Canada
| | - Graham N George
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada.,Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9, Canada
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Zhang Z, Chow SY, De Guzman R, Joh NH, Joubert MK, Richardson J, Shah B, Wikström M, Zhou ZS, Wypych J. A Mass Spectrometric Characterization of Light-Induced Modifications in Therapeutic Proteins. J Pharm Sci 2022; 111:1556-1564. [DOI: 10.1016/j.xphs.2022.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 02/04/2022] [Accepted: 02/04/2022] [Indexed: 12/15/2022]
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4
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Okbinoglu T, Kennepohl P. Nature of S-N Bonding in Sulfonamides and Related Compounds: Insights into π-Bonding Contributions from Sulfur K-Edge X-ray Absorption Spectroscopy. J Phys Chem A 2021; 125:615-620. [PMID: 33410696 DOI: 10.1021/acs.jpca.0c09768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Molecules containing sulfur-nitrogen bonds, like sulfonamides, have long been of interest because of their many uses and interesting chemical properties. Understanding the factors that cause sulfonamide reactivity is important, yet there continues to be controversy regarding the relevance of S-N π bonding in describing these species. In this paper, we use sulfur K-edge X-ray absorption spectroscopy (XAS) in conjunction with density functional theory (DFT) to investigate the role of S3p contributions to π-bonding in sulfonamides, sulfinamides, and sulfenamides. We explore the nature of the electron distribution of the sulfur atom to its nearest neighbors and widen our scope to its effects on rotational barriers along the sulfur-nitrogen axis. The experimental XAS data together with time-dependent DFT calculations confirm that sulfonamides-and the other sulfinated amides in this series-have essentially no S-N π bonding involving S3p contributions and that electron repulsion is the dominant force affecting rotational barriers along the S-N axis.
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Affiliation(s)
- Tulin Okbinoglu
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver BC V6T 1Z1, Canada
| | - Pierre Kennepohl
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver BC V6T 1Z1, Canada.,Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary AB T2N 1N4, Canada
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Vogt LI, Cotelesage JJH, Dolgova NV, Titus CJ, Sharifi S, George SJ, Pickering IJ, George GN. X-ray absorption spectroscopy of organic sulfoxides. RSC Adv 2020; 10:26229-26238. [PMID: 35519739 PMCID: PMC9055334 DOI: 10.1039/d0ra04653a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 07/02/2020] [Indexed: 01/21/2023] Open
Abstract
Organic sulfoxides, a group of compounds containing the sulfinyl S[double bond, length as m-dash]O group, are widespread in nature, important in health and disease, and used in a variety of applications in the pharmaceutical industry. We have examined the sulfur K-edge X-ray absorption near-edge spectra of a range of different sulfoxides and find that their spectra are remarkably similar. Spectra show an intense absorption peak that is comprised of two transitions; a S 1s → (S-O)σ* and a S 1s → [(S-O)π* + (S-C)σ*] transition. In most cases these are sufficiently close in energy that they are not properly resolved; however for dimethylsulfoxide the separation between these transitions increases in aqueous solution due to hydrogen bonding to the sulfinyl oxygen. We also examined tetrahydrothiophene sulfoxide using both the sulfur and oxygen K-edge. This compound has a mild degree of ring strain at the sulfur atom, which changes the energies of the two transitions so that the S 1s → [(S-O)π* + (S-C)σ*] is below the S 1s → (S-O)σ*. A comparison of the oxygen K-edge X-ray absorption near-edge spectra of tetrahydrothiophene sulfoxide with that of an unhindered sulfoxide shows little change, indicating that the electronic environment of oxygen is very similar.
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Affiliation(s)
- Linda I Vogt
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan Saskatoon Saskatchewan S7N 5E2 Canada
| | - Julien J H Cotelesage
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan Saskatoon Saskatchewan S7N 5E2 Canada
| | - Natalia V Dolgova
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan Saskatoon Saskatchewan S7N 5E2 Canada
| | - Charles J Titus
- Department of Physics, Stanford University Stanford California 94305 USA
| | - Samin Sharifi
- Chevron Energy Technology Company Richmond California 94802 USA
| | - Simon J George
- Simon Scientific 200 Allston Way, Unit 232 Berkeley California 94701 USA
| | - Ingrid J Pickering
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan Saskatoon Saskatchewan S7N 5E2 Canada
- Department of Chemistry, University of Saskatchewan Saskatoon Saskatchewan S7N 5C9 Canada
| | - Graham N George
- Molecular and Environmental Sciences Group, Department of Geological Sciences, University of Saskatchewan Saskatoon Saskatchewan S7N 5E2 Canada
- Department of Chemistry, University of Saskatchewan Saskatoon Saskatchewan S7N 5C9 Canada
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Synthesis and biological evaluation of quercetin and resveratrol peptidyl derivatives as potential anticancer and antioxidant agents. Amino Acids 2018; 51:319-329. [PMID: 30392096 DOI: 10.1007/s00726-018-2668-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 10/16/2018] [Indexed: 12/26/2022]
Abstract
Quercetin and resveratrol are polyphenolic compounds, members of the flavonoid and the stilbene family, respectively, both medicinally important as dietary anticancer and antioxidant agents. They are present in a variety of foods-including fruits, vegetables, tea, wine, as well as other dietary supplements-and are responsible for various health benefits. Different quercetin and resveratrol esters of Leu/Met-enkephalin and tetrapeptide Leu-Ser-Lys-Leu (LSKL) were synthesized as model systems for monitoring the influence of the peptides on biological activity of resveratrol and quercetin. General formula of the main peptidyl-quercetin derivatives is 2-[3-(aa)n-4-hydroxyphenyl]-3,5,7-tri-hydroxy-4H-1-benzopyran-4-on, and the general formula of the main peptidyl-resveratrol derivatives is (E)-5-[4-(aa)n)styryl]benzene-1,3-diol. The antioxidant and anticancer activities of prepared compounds were investigated. Significant anticancer activity was obtained for the LSKL-based both quercetin and resveratrol derivatives. All prepared compounds exhibit antioxidant activity, in particular quercetin derivative containing Met-enkephalin.
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Ochmann M, Hussain A, von Ahnen I, Cordones AA, Hong K, Lee JH, Ma R, Adamczyk K, Kim TK, Schoenlein RW, Vendrell O, Huse N. UV-Photochemistry of the Disulfide Bond: Evolution of Early Photoproducts from Picosecond X-ray Absorption Spectroscopy at the Sulfur K-Edge. J Am Chem Soc 2018; 140:6554-6561. [PMID: 29771112 DOI: 10.1021/jacs.7b13455] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We have investigated dimethyl disulfide as the basic moiety for understanding the photochemistry of disulfide bonds, which are central to a broad range of biochemical processes. Picosecond time-resolved X-ray absorption spectroscopy at the sulfur K-edge provides unique element-specific insight into the photochemistry of the disulfide bond initiated by 267 nm femtosecond pulses. We observe a broad but distinct transient induced absorption spectrum which recovers on at least two time scales in the nanosecond range. We employed RASSCF electronic structure calculations to simulate the sulfur-1s transitions of multiple possible chemical species, and identified the methylthiyl and methylperthiyl radicals as the primary reaction products. In addition, we identify disulfur and the CH2S thione as the secondary reaction products of the perthiyl radical that are most likely to explain the observed spectral and kinetic signatures of our experiment. Our study underscores the importance of elemental specificity and the potential of time-resolved X-ray spectroscopy to identify short-lived reaction products in complex reaction schemes that underlie the rich photochemistry of disulfide systems.
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Affiliation(s)
- Miguel Ochmann
- Department of Physics , University of Hamburg and Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science , 22761 Hamburg , Germany
| | - Abid Hussain
- Department of Physics , University of Hamburg and Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science , 22761 Hamburg , Germany
| | - Inga von Ahnen
- Department of Physics , University of Hamburg and Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science , 22761 Hamburg , Germany
| | - Amy A Cordones
- Ultrafast X-ray Science Lab, Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Kiryong Hong
- Department of Chemistry and Chemistry Institute of Functional Materials , Pusan National University , Busan 46241 , South Korea
| | - Jae Hyuk Lee
- Ultrafast X-ray Science Lab, Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Rory Ma
- Department of Chemistry and Chemistry Institute of Functional Materials , Pusan National University , Busan 46241 , South Korea
| | - Katrin Adamczyk
- Department of Physics , University of Hamburg and Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science , 22761 Hamburg , Germany
| | - Tae Kyu Kim
- Department of Chemistry and Chemistry Institute of Functional Materials , Pusan National University , Busan 46241 , South Korea
| | - Robert W Schoenlein
- Ultrafast X-ray Science Lab, Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Oriol Vendrell
- Center for Free-Electron Laser Science , DESY and The Hamburg Centre for Ultrafast Imaging , 22607 Hamburg , Germany
| | - Nils Huse
- Department of Physics , University of Hamburg and Max Planck Institute for the Structure and Dynamics of Matter, Center for Free Electron Laser Science , 22761 Hamburg , Germany
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Sulfur Radicals and Their Application. Top Curr Chem (Cham) 2018; 376:22. [DOI: 10.1007/s41061-018-0197-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 04/11/2018] [Indexed: 12/11/2022]
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Thiruppathi D, Karuppasamy P, Ganesan M, Sivasubramanian VK, Rajendran T, Rajagopal S. Electron transfer reactions of methionine peptides with photochemically generated ruthenium(III)–polypyridyl complexes. J Photochem Photobiol A Chem 2014. [DOI: 10.1016/j.jphotochem.2014.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Electron Transfer Reactions of Photochemically Generated Ruthenium(III)-Polypyridyl Complexes with Methionines. INT J CHEM KINET 2014. [DOI: 10.1002/kin.20874] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Ignasiak MT, Marciniak B, Houée-Levin C. A Long Story of Sensitized One-Electron Photo-oxidation of Methionine. Isr J Chem 2014. [DOI: 10.1002/ijch.201300109] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Abstract
Photo-induced damage to proteins occurs via multiple pathways. Direct damage induced by UVB (λ 280-320 nm) and UVA radiation (λ 320-400 nm) is limited to a small number of amino acid residues, principally tryptophan (Trp), tyrosine (Tyr), histidine (His) and disulfide (cystine) residues, with this occurring via both excited state species and radicals. Indirect protein damage can occur via singlet oxygen ((1)O(2)(1)Δ(g)), with this resulting in damage to Trp, Tyr, His, cystine, cysteine (Cys) and methionine (Met) residues. Although initial damage is limited to these residues multiple secondary processes, that occur both during and after radiation exposure, can result in damage to other intra- and inter-molecular sites. Secondary damage can arise via radicals (e.g. Trp, Tyr and Cys radicals), from reactive intermediates generated by (1)O(2) (e.g. Trp, Tyr and His peroxides) and via molecular reactions of photo-products (e.g. reactive carbonyls). These processes can result in protein fragmentation, aggregation, altered physical and chemical properties (e.g. hydrophobicity and charge) and modulated biological turnover. Accumulating evidence implicates these events in cellular and tissue dysfunction (e.g. apoptosis, necrosis and altered cell signaling), and multiple human pathologies.
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Affiliation(s)
- David I Pattison
- The Heart Research Institute, 7 Eliza Street, Newtown, Sydney, NSW 2042, Australia
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Long LH, Wu PF, Guan XL, Zhang JQ, Jin Y, Zhang Z, Wang Y, Li YY, Chen JG, Wang F. Determination of protein-bound methionine oxidation in the hippocampus of adult and old rats by LC-ESI-ITMS method after microwave-assisted proteolysis. Anal Bioanal Chem 2011; 399:2267-74. [PMID: 21207014 DOI: 10.1007/s00216-010-4604-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2010] [Revised: 11/18/2010] [Accepted: 12/13/2010] [Indexed: 11/30/2022]
Abstract
Protein-bound methionine (Met) oxidation has been associated with normal aging and a variety of age-related diseases, including Alzheimer's disease and Parkinson's disease. Monitoring the changes of protein-bound methionine content in the brain in response to normal aging and oxidative stress is of great interest and could be used as an indicator of oxidative stress of rats in pathological conditions. We have developed a rapid analytical method for the determination of oxidized products of protein-bound methionine in rat brain. The assay involved rapid acid proteolysis with microwave irradiation and solid-phase extraction of the free amino acids followed by LC-ESI-ITMS analysis. Detection was achieved in positive ionization with an ion trap mass spectrometer operating in multiple-reaction monitoring mode. The calibration curves of the analytes were linear (r(2) > 0.99) in the range between 0.098 and 1.560 μg/mL. Intra- and inter-day relative standard deviation percentages were <9% and <8%, respectively. The assay performance was sufficient to support a rapid analytical tool for monitoring brain protein-bound methionine oxidation levels. The content of protein-bound Met and methionine sulfoxide (MetO) in the hippocampus of adult and old rats with or without H(2)O(2) treatment was determined by employing the new method. The content of protein-bound MetO was significantly increased in old rats after exposure to H(2)O(2). This result indicates increased sensitivity to Met oxidation in the hippocampus of old rats.
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Affiliation(s)
- Li-Hong Long
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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Lucas HR, Lee JC. Effect of dioxygen on copper(II) binding to alpha-synuclein. J Inorg Biochem 2009; 104:245-9. [PMID: 20064662 DOI: 10.1016/j.jinorgbio.2009.12.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 11/18/2009] [Accepted: 12/14/2009] [Indexed: 11/24/2022]
Abstract
Using the fluorescent amino acid tryptophan (Trp), we have characterized the copper(II) binding of F4W alpha-synuclein in the presence and absence of dioxygen at neutral pH. Variations in Trp fluorescence indicate that copper(II) binding is enhanced by the presence of dioxygen, with the apparent dissociation constant (K(d(app))) changing from 100nM (anaerobic) to 10nM (aerobic). To investigate the possible role of methionine oxidation, complementary work focused on synthetic peptide models of the N-terminal Cu(II)-alpha-syn site, MDV(F/W) and M( *)DV(F/W), where M( *)=methionine sulfoxide. Furthermore, we employed circular dichroism (CD) spectroscopy to demonstrate that the phenyl-to-indole (F-->W) substitution does not alter copper(II) binding properties and to confirm the 1:1 metal-peptide binding stoichiometry. CD comparisons also revealed that Met1 oxidation does not affect the copper-peptide conformation and further suggested the possible existence of a Cu(II)-Trp/Phe (cation-pi) interaction.
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Affiliation(s)
- Heather R Lucas
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-8013, United States
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Glass RS, Hug GL, Schöneich C, Wilson GS, Kuznetsova L, Lee TM, Ammam M, Lorance E, Nauser T, Nichol GS, Yamamoto T. Neighboring amide participation in thioether oxidation: relevance to biological oxidation. J Am Chem Soc 2009; 131:13791-805. [PMID: 19772365 DOI: 10.1021/ja904895u] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
To investigate neighboring amide participation in thioether oxidation, which may be relevant to brain oxidative stress accompanying beta-amyloid peptide aggregation, conformationally constrained methylthionorbornyl derivatives with amido moieties were synthesized and characterized, including an X-ray crystallographic study of one of them. Electrochemical oxidation of these compounds, studied by cyclic voltammetry, revealed that their oxidation peak potentials were less positive for those compounds in which neighboring group participation was geometrically possible. Pulse radiolysis studies provided evidence for bond formation between the amide moiety and sulfur on one-electron oxidation in cases where the moieties are juxtaposed. Furthermore, molecular constraints in spiro analogues revealed that S-O bonds are formed on one-electron oxidation. DFT calculations suggest that isomeric sigma*(SO) radicals are formed in these systems.
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Affiliation(s)
- Richard S Glass
- Department of Chemistry, The University of Arizona, Tucson, Arizona 85721, USA.
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