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Telegina TA, Vechtomova YL, Borzova VA, Buglak AA. Tetrahydrobiopterin as a Trigger for Vitiligo: Phototransformation during UV Irradiation. Int J Mol Sci 2023; 24:13586. [PMID: 37686391 PMCID: PMC10487557 DOI: 10.3390/ijms241713586] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 08/25/2023] [Accepted: 08/30/2023] [Indexed: 09/10/2023] Open
Abstract
Vitiligo is a type of hypomelanosis. Tetrahydrobiopterin (H4Bip), the coenzyme of the initial stage of melanogenesis, appears to be a trigger for vitiligo. H4Bip is present in vitiligo in 3-5-fold excess and causes oxidative stress by triggering an autocatalytic cycle of excess hydrogen peroxide synthesis. Using quantum-chemical calculations, we have evaluated the possibility of H4Bip reactions occurring in the dark and under ultraviolet (UV) irradiation, including the formation of dihydropterin dimers. In order to simulate the oxidative stress, oxidative modification of human serum albumin (HSA) has been carried out in the presence of excessive H4Bip using the fluorescence method. The fraction of oxidized protein (FOP) has been calculated. It has been established that there is a strong oxidative modification of amino acids chromophores (tryptophan and tyrosine) in the protein (FOP 0.64). Under UV irradiation of the system (HSA + H4Bip), FOP is reduced to 0.39. Apparently, a part of H4Bip transforms into dihydropterin dimers and does not participate in the oxidative modification of the protein. The data on oxidative modification of HSA are consistent with dynamic light scattering: H4Bip promotes HSA aggregation with the formation of particles with a hydrodynamic radius Rh ≥ 2000 nm, which can become immunogenic.
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Affiliation(s)
- Taisiya A. Telegina
- Research Center of Biotechnology of the Russian Academy of Sciences, Bach Institute of Biochemistry, 119071 Moscow, Russia; (T.A.T.); (Y.L.V.); (V.A.B.)
| | - Yuliya L. Vechtomova
- Research Center of Biotechnology of the Russian Academy of Sciences, Bach Institute of Biochemistry, 119071 Moscow, Russia; (T.A.T.); (Y.L.V.); (V.A.B.)
| | - Vera A. Borzova
- Research Center of Biotechnology of the Russian Academy of Sciences, Bach Institute of Biochemistry, 119071 Moscow, Russia; (T.A.T.); (Y.L.V.); (V.A.B.)
| | - Andrey A. Buglak
- Faculty of Physics, Saint Petersburg State University, 199034 Saint Petersburg, Russia
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Insights into Molecular Structure of Pterins Suitable for Biomedical Applications. Int J Mol Sci 2022; 23:ijms232315222. [PMID: 36499560 PMCID: PMC9737128 DOI: 10.3390/ijms232315222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/22/2022] [Accepted: 11/30/2022] [Indexed: 12/07/2022] Open
Abstract
Pterins are an inseparable part of living organisms. Pterins participate in metabolic reactions mostly as tetrahydropterins. Dihydropterins are usually intermediates of these reactions, whereas oxidized pterins can be biomarkers of diseases. In this review, we analyze the available data on the quantum chemistry of unconjugated pterins as well as their photonics. This gives a comprehensive overview about the electronic structure of pterins and offers some benefits for biomedicine applications: (1) one can affect the enzymatic reactions of aromatic amino acid hydroxylases, NO synthases, and alkylglycerol monooxygenase through UV irradiation of H4pterins since UV provokes electron donor reactions of H4pterins; (2) the emission properties of H2pterins and oxidized pterins can be used in fluorescence diagnostics; (3) two-photon absorption (TPA) should be used in such pterin-related infrared therapy because single-photon absorption in the UV range is inefficient and scatters in vivo; (4) one can affect pathogen organisms through TPA excitation of H4pterin cofactors, such as the molybdenum cofactor, leading to its detachment from proteins and subsequent oxidation; (5) metal nanostructures can be used for the UV-vis, fluorescence, and Raman spectroscopy detection of pterin biomarkers. Therefore, we investigated both the biochemistry and physical chemistry of pterins and suggested some potential prospects for pterin-related biomedicine.
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A model to understand type I oxidations of biomolecules photosensitized by pterins. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY 2021. [DOI: 10.1016/j.jpap.2021.100045] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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Buglak AA, Telegina TA, Vechtomova YL, Kritsky MS. Autoxidation and photooxidation of tetrahydrobiopterin: a theoretical study. Free Radic Res 2021; 55:499-509. [PMID: 33283562 DOI: 10.1080/10715762.2020.1860213] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 11/07/2020] [Accepted: 12/02/2020] [Indexed: 01/24/2023]
Abstract
Pterins are naturally occurring pigments and enzyme cofactors widespread in living organisms. Tetrahydrobiopterin (H4Bip) is a coenzyme of aromatic amino acid hydroxylases, NO-synthases, and alkylglycerol monooxygenases. This coenzyme is prone to oxidation in the presence of molecular oxygen, a so-called autoxidation. The reactions participating in H4Bip autoxidation are well known. However, our study is an attempt to evaluate theoretically the feasibility of reactions participating in autoxidation. To do so, we have calculated the Gibbs free energy of elementary reactions between H4Bip, its derivatives, molecular oxygen, and reactive oxygen species (ROS). In the last few years, we have established the photosensitized oxidation of H4Bip experimentally. Thus, we have also evaluated the feasibility of H4Bip photooxidation reactions, which may occur according to both type-I and type-II photosensitized oxidation. We calculated Fukui indices for H4Bip and found particular atoms in the molecule that interact with nucleophiles (for example, singlet oxygen 1O2) and radicals (in particular, molecular oxygen 3O2). Therefore, we evaluated the probability of H4Bip autoxidation reactions, photooxidation reactions, and the reactivity of particular atoms in H4Bip molecule using the theoretical methods of quantum chemistry.
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Affiliation(s)
- Andrey A Buglak
- Physical Faculty, St. Petersburg State University, St. Petersburg, Russia
| | - Taisiya A Telegina
- Physical Faculty, St. Petersburg State University, St. Petersburg, Russia
- Laboratory of ecological and evolutionary biochemistry, A. N. Bach Institute of Biochemistry, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Yulia L Vechtomova
- Laboratory of ecological and evolutionary biochemistry, A. N. Bach Institute of Biochemistry, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail S Kritsky
- Laboratory of ecological and evolutionary biochemistry, A. N. Bach Institute of Biochemistry, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, Russia
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Photo-induced protein oxidation: mechanisms, consequences and medical applications. Essays Biochem 2019; 64:33-44. [DOI: 10.1042/ebc20190044] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/20/2019] [Accepted: 11/25/2019] [Indexed: 01/10/2023]
Abstract
Abstract
Irradiation from the sun has played a crucial role in the origin and evolution of life on the earth. Due to the presence of ozone in the stratosphere most of the hazardous irradiation is absorbed, nonetheless UVB, UVA, and visible light reach the earth’s surface. The high abundance of proteins in most living organisms, and the presence of chromophores in the side chains of certain amino acids, explain why these macromolecules are principal targets when biological systems are illuminated. Light absorption triggers the formation of excited species that can initiate photo-modification of proteins. The major pathways involve modifications derived from direct irradiation and photo-sensitized reactions. In this review we explored the basic concepts behind these photochemical pathways, with special emphasis on the photosensitized mechanisms (type 1 and type 2) leading to protein oxidation, and how this affects protein structure and functions. Finally, a description of the photochemical reactions involved in some human diseases, and medical applications of protein oxidation are presented.
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Theoretical study of photoreactions between oxidized pterins and molecular oxygen. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2018.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Liu L, Sun B. pH-related fluorescence quenching mechanism of pterin derivatives and the effects of 6-site substituents. CAN J CHEM 2018. [DOI: 10.1139/cjc-2017-0644] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
2-Amino-4-hydroxypteridine (pterin) and its derivatives serve as photooxidants and exhibit strong fluorescence. When they interact with hydrogen acceptors such as acetate and phosphate, their fluorescences are significantly quenched in acidic conditions (pH 4.9–5.5) but are retained in basic conditions (pH 10.0–10.5). This pH-related fluorescence quenching mechanism of pterin and its derivatives are fully investigated by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT). Pterin and its derivatives are demonstrated to show favorable excited-state proton transfer (ESPT) abilities in acidic conditions that induce the experimentally observed fluorescence quenching. In contrast, the ESPT processes are found to be retarded due to the lack of strong hydrogen-bonding interactions in basic environments, which sustain their fluorescence. Interestingly, these ESPT processes are found to show different site specificities depending on the 6-site substituents. The introduction of electron-donating substituent activates the N1 site, making it the preferred ESPT site. By contrast, the introduction of an electron-withdrawing substituent activates the N5 site, making it the favorable ESPT site. The substitutions of different functional groups are found to affect the locations of acidic centers during the excitation and relaxation processes. This further affects the hydrogen-bonding patterns and ultimately brings site specificity to the ESPT process.
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Affiliation(s)
- Lei Liu
- College of Chemical and Materials Engineering, Anhui Science and Technology University, Fengyang, 233100, China
| | - Bingqing Sun
- College of Resource and Environment, Anhui Science and Technology University, Fengyang, 233100, China
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Dantola ML, Reid LO, Castaño C, Lorente C, Oliveros E, Thomas AH. Photosensitization of peptides and proteins by pterin derivatives. Pteridines 2017. [DOI: 10.1515/pterid-2017-0013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Abstract
Proteins are one of the preferential targets of the photosensitized damaging effects of ultraviolet (UV) radiation on biological system. Pterins belong to a family of heterocyclic compounds, which are widespread in living systems and participate in relevant biological functions. In pathological conditions, such as vitiligo, oxidized pterins accumulate in the white skin patches of patients suffering this depigmentation disorder. It is known that pterins are able to photosensitize damage in nucleotides and DNA by type I (electron transfer) and type II (singlet oxygen) mechanisms. Recently, it has been demonstrated that proteins and its components may also be damaged when solutions containing both proteins and pterin are exposed to UV-A radiation. Therefore, given the biological and medical relevance of the photosensitizing properties of these molecules, we present in this article an overview of the capability of different pterin derivatives to photoinduce damage in proteins present in the skin, focusing our attention on the chemical modifications of tyrosine and tryptophan residues.
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Affiliation(s)
- Maria Laura Dantola
- Facultad de Ciencias Exactas, Departamento de Química, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA) , Universidad Nacional de La Plata, CCT La Plata-CONICET , Casilla de Correo 16, Sucursal 4 , 1900 La Plata , Argentina
| | - Lara O. Reid
- Facultad de Ciencias Exactas, Departamento de Química, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA) , Universidad Nacional de La Plata, CCT La Plata-CONICET , Casilla de Correo 16, Sucursal 4 , 1900 La Plata , Argentina
| | - Carolina Castaño
- Facultad de Ciencias Exactas, Departamento de Química, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA) , Universidad Nacional de La Plata, CCT La Plata-CONICET , Casilla de Correo 16, Sucursal 4 , 1900 La Plata , Argentina
| | - Carolina Lorente
- Facultad de Ciencias Exactas, Departamento de Química, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA) , Universidad Nacional de La Plata, CCT La Plata-CONICET , Casilla de Correo 16, Sucursal 4 , 1900 La Plata , Argentina
| | - Esther Oliveros
- Laboratoire des Interactions Moléculaires et Réactivité Chimique et Photochimique (IMRCP), UMR 5623-CNRS/UPS , Université Toulouse III (Paul Sabatier ), 118, route de Narbonne , F-31062 Toulouse Cédex 9 , France
| | - Andrés H. Thomas
- Facultad de Ciencias Exactas, Departamento de Química, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA) , Universidad Nacional de La Plata, CCT La Plata-CONICET , Casilla de Correo 16, Sucursal 4 , 1900 La Plata , Argentina
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Reid LO, Roman EA, Thomas AH, Dántola ML. Photooxidation of Tryptophan and Tyrosine Residues in Human Serum Albumin Sensitized by Pterin: A Model for Globular Protein Photodamage in Skin. Biochemistry 2016; 55:4777-86. [DOI: 10.1021/acs.biochem.6b00420] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lara O. Reid
- Instituto
de Investigaciones Fisicoquímicas Teóricas y Aplicadas
(INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CCT La Plata-CONICET, Casilla de Correo 16, Sucursal 4, 1900 La Plata, Argentina
| | - Ernesto A. Roman
- Instituto
de Química y Físico-Químicas Biológicas
(IQUIFIB), Universidad de Buenos Aires, Junín 956, 1113 Buenos Aires, Argentina
| | - Andrés H. Thomas
- Instituto
de Investigaciones Fisicoquímicas Teóricas y Aplicadas
(INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CCT La Plata-CONICET, Casilla de Correo 16, Sucursal 4, 1900 La Plata, Argentina
| | - M. Laura Dántola
- Instituto
de Investigaciones Fisicoquímicas Teóricas y Aplicadas
(INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CCT La Plata-CONICET, Casilla de Correo 16, Sucursal 4, 1900 La Plata, Argentina
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Thomas AH, Catalá Á, Vignoni M. Soybean phosphatidylcholine liposomes as model membranes to study lipid peroxidation photoinduced by pterin. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1858:139-45. [PMID: 26551322 DOI: 10.1016/j.bbamem.2015.11.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 10/15/2015] [Accepted: 11/05/2015] [Indexed: 11/16/2022]
Abstract
Oxidized pterins, efficient photosensitizers under UVA irradiation, accumulate in the skin of patients suffering from vitiligo, a chronic depigmentation disorder. Soybean phosphatidylcholine (SoyPC) liposomes were employed as model membranes to investigate if pterin (Ptr), the parent compound of oxidized pterins, is able to photoinduced lipid peroxidation. Size exclusion chromatography and dialysis experiments showed that Ptr is not encapsulated inside the liposomes and the lipid membrane is permeable to this compound. The formation of conjugated dienes and trienes, upon UVA irradiation, was followed by absorption at 234 and 270 nm, respectively. The photoproducts were characterized by mass spectrometry and oxygenation of SoyPC was demonstrated. In addition, analysis of MS/MS spectra suggested the formation hydroperoxides. Finally, the biological implications of the findings are discussed.
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Affiliation(s)
- Andrés H Thomas
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), CCT La Plata-CONICET, Casilla de Correo 16, Sucursal 4, (1900) La Plata, Argentina
| | - Ángel Catalá
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), CCT La Plata-CONICET, Casilla de Correo 16, Sucursal 4, (1900) La Plata, Argentina
| | - Mariana Vignoni
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP), CCT La Plata-CONICET, Casilla de Correo 16, Sucursal 4, (1900) La Plata, Argentina.
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Laura Dántola M, Zurbano BN, Thomas AH. Photoinactivation of tyrosinase sensitized by folic acid photoproducts. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 149:172-9. [DOI: 10.1016/j.jphotobiol.2015.06.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 05/11/2015] [Accepted: 06/03/2015] [Indexed: 02/08/2023]
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12
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Thomas AH, Zurbano BN, Lorente C, Santos J, Roman EA, Laura Dántola M. Chemical changes in bovine serum albumin photoinduced by pterin. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2014; 141:262-8. [DOI: 10.1016/j.jphotobiol.2014.10.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/23/2014] [Accepted: 10/14/2014] [Indexed: 11/28/2022]
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Liu L, Yang D, Li P. pH-Related and Site-Specific Excited-State Proton Transfer from Pterin to Acetate. J Phys Chem B 2014; 118:11707-14. [DOI: 10.1021/jp5082017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Lei Liu
- State Key Laboratory of Molecular
Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- State Key Laboratory
of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Dapeng Yang
- State Key Laboratory of Molecular
Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Physics Laboratory, North China University of Water Resources and Electric Power, Zhengzhou 450045, China
| | - Peng Li
- State Key Laboratory of Molecular
Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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Denofrio MP, Ogilby PR, Thomas AH, Lorente C. Selective quenching of triplet excited states of pteridines. Photochem Photobiol Sci 2014; 13:1058-65. [DOI: 10.1039/c4pp00079j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Castaño C, Lorente C, Martins-Froment N, Oliveros E, Thomas AH. Degradation of α-melanocyte-stimulating hormone photosensitized by pterin. Org Biomol Chem 2014; 12:3877-86. [DOI: 10.1039/c4ob00434e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Castaño C, Dántola ML, Oliveros E, Thomas AH, Lorente C. Oxidation of Tyrosine Photoinduced by Pterin in Aqueous Solution. Photochem Photobiol 2013; 89:1448-55. [DOI: 10.1111/php.12099] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 05/07/2013] [Indexed: 12/01/2022]
Affiliation(s)
- Carolina Castaño
- Departamento de Química; Facultad de Ciencias Exactas; Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA); Universidad Nacional de La Plata; CCT La Plata-CONICET; La Plata Argentina
| | - María L. Dántola
- Departamento de Química; Facultad de Ciencias Exactas; Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA); Universidad Nacional de La Plata; CCT La Plata-CONICET; La Plata Argentina
| | - Esther Oliveros
- Laboratoire des Interactions Moléculaires Réactivité Chimique et Photochimique (IMRCP); UMR 5623-CNRS/UPS; Université Toulouse III (Paul Sabatier); Toulouse Cédex France
| | - Andrés H. Thomas
- Departamento de Química; Facultad de Ciencias Exactas; Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA); Universidad Nacional de La Plata; CCT La Plata-CONICET; La Plata Argentina
| | - Carolina Lorente
- Departamento de Química; Facultad de Ciencias Exactas; Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA); Universidad Nacional de La Plata; CCT La Plata-CONICET; La Plata Argentina
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Thomas AH, Lorente C, Roitman K, Morales MM, Dántola ML. Photosensitization of bovine serum albumin by pterin: A mechanistic study. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2013; 120:52-8. [DOI: 10.1016/j.jphotobiol.2013.01.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Revised: 01/14/2013] [Accepted: 01/15/2013] [Indexed: 10/27/2022]
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