Mechanism of electron transfer processes photoinduced by lumazine
- Autores
- Denofrio, María Paula; Dántola, María Laura; Vicendo, Patricia; Oliveros, Esther; Thomas, Andrés Héctor; Lorente, Carolina
- Año de publicación
- 2012
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- UV-A (320–400 nm) and UV-B (280–320 nm) radiation causes damage to DNA and other biomolecules through reactions induced by different endogenous or exogenous photosensitizers. Lumazines are heterocyclic compounds present in biological systems as biosynthetic precursors and/or products of metabolic degradation. The parent and unsubstituted compound called lumazine (pteridine-2,4(1,3H)-dione; Lum) is able to act as photosensitizer through electron transfer-initiated oxidations. To get further insight into the mechanisms involved, we have studied in detail the oxidation of 2′-deoxyadenosine 5′-monophosphate (dAMP) photosensitized by Lum in aqueous solution. After UV-A or UV-B excitation of Lum and formation of its triplet excited state (³Lum*), three reaction pathways compete for the deactivation of the latter: intersystem crossing to singlet ground state, energy transfer to O₂, and electron transfer between dAMP and ³Lum* yielding the corresponding pair of radical ions (Lum˙⁻ and dAMP˙⁺). In the following step, the electron transfer from Lum˙⁻ to O₂ regenerates Lum and forms the superoxide anion (O₂˙⁻), which undergoes disproportionation into H₂O₂ and O₂. Finally dAMP˙⁺ participates in subsequent reactions to yield products.
Facultad de Ciencias Exactas
Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas - Materia
-
Ciencias Exactas
electron transfer
lumazine - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- http://creativecommons.org/licenses/by-nc-sa/4.0/
- Repositorio
- Institución
- Universidad Nacional de La Plata
- OAI Identificador
- oai:sedici.unlp.edu.ar:10915/130519
Ver los metadatos del registro completo
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Mechanism of electron transfer processes photoinduced by lumazineDenofrio, María PaulaDántola, María LauraVicendo, PatriciaOliveros, EstherThomas, Andrés HéctorLorente, CarolinaCiencias Exactaselectron transferlumazineUV-A (320–400 nm) and UV-B (280–320 nm) radiation causes damage to DNA and other biomolecules through reactions induced by different endogenous or exogenous photosensitizers. Lumazines are heterocyclic compounds present in biological systems as biosynthetic precursors and/or products of metabolic degradation. The parent and unsubstituted compound called lumazine (pteridine-2,4(1,3H)-dione; Lum) is able to act as photosensitizer through electron transfer-initiated oxidations. To get further insight into the mechanisms involved, we have studied in detail the oxidation of 2′-deoxyadenosine 5′-monophosphate (dAMP) photosensitized by Lum in aqueous solution. After UV-A or UV-B excitation of Lum and formation of its triplet excited state (³Lum*), three reaction pathways compete for the deactivation of the latter: intersystem crossing to singlet ground state, energy transfer to O₂, and electron transfer between dAMP and ³Lum* yielding the corresponding pair of radical ions (Lum˙⁻ and dAMP˙⁺). In the following step, the electron transfer from Lum˙⁻ to O₂ regenerates Lum and forms the superoxide anion (O₂˙⁻), which undergoes disproportionation into H₂O₂ and O₂. Finally dAMP˙⁺ participates in subsequent reactions to yield products.Facultad de Ciencias ExactasInstituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas2012info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf409-417http://sedici.unlp.edu.ar/handle/10915/130519enginfo:eu-repo/semantics/altIdentifier/issn/1474-9092info:eu-repo/semantics/altIdentifier/issn/1474-905Xinfo:eu-repo/semantics/altIdentifier/doi/10.1039/c1pp05315ainfo:eu-repo/semantics/altIdentifier/pmid/22212735info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:32:07Zoai:sedici.unlp.edu.ar:10915/130519Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:32:08.31SEDICI (UNLP) - Universidad Nacional de La Platafalse |
dc.title.none.fl_str_mv |
Mechanism of electron transfer processes photoinduced by lumazine |
title |
Mechanism of electron transfer processes photoinduced by lumazine |
spellingShingle |
Mechanism of electron transfer processes photoinduced by lumazine Denofrio, María Paula Ciencias Exactas electron transfer lumazine |
title_short |
Mechanism of electron transfer processes photoinduced by lumazine |
title_full |
Mechanism of electron transfer processes photoinduced by lumazine |
title_fullStr |
Mechanism of electron transfer processes photoinduced by lumazine |
title_full_unstemmed |
Mechanism of electron transfer processes photoinduced by lumazine |
title_sort |
Mechanism of electron transfer processes photoinduced by lumazine |
dc.creator.none.fl_str_mv |
Denofrio, María Paula Dántola, María Laura Vicendo, Patricia Oliveros, Esther Thomas, Andrés Héctor Lorente, Carolina |
author |
Denofrio, María Paula |
author_facet |
Denofrio, María Paula Dántola, María Laura Vicendo, Patricia Oliveros, Esther Thomas, Andrés Héctor Lorente, Carolina |
author_role |
author |
author2 |
Dántola, María Laura Vicendo, Patricia Oliveros, Esther Thomas, Andrés Héctor Lorente, Carolina |
author2_role |
author author author author author |
dc.subject.none.fl_str_mv |
Ciencias Exactas electron transfer lumazine |
topic |
Ciencias Exactas electron transfer lumazine |
dc.description.none.fl_txt_mv |
UV-A (320–400 nm) and UV-B (280–320 nm) radiation causes damage to DNA and other biomolecules through reactions induced by different endogenous or exogenous photosensitizers. Lumazines are heterocyclic compounds present in biological systems as biosynthetic precursors and/or products of metabolic degradation. The parent and unsubstituted compound called lumazine (pteridine-2,4(1,3H)-dione; Lum) is able to act as photosensitizer through electron transfer-initiated oxidations. To get further insight into the mechanisms involved, we have studied in detail the oxidation of 2′-deoxyadenosine 5′-monophosphate (dAMP) photosensitized by Lum in aqueous solution. After UV-A or UV-B excitation of Lum and formation of its triplet excited state (³Lum*), three reaction pathways compete for the deactivation of the latter: intersystem crossing to singlet ground state, energy transfer to O₂, and electron transfer between dAMP and ³Lum* yielding the corresponding pair of radical ions (Lum˙⁻ and dAMP˙⁺). In the following step, the electron transfer from Lum˙⁻ to O₂ regenerates Lum and forms the superoxide anion (O₂˙⁻), which undergoes disproportionation into H₂O₂ and O₂. Finally dAMP˙⁺ participates in subsequent reactions to yield products. Facultad de Ciencias Exactas Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas |
description |
UV-A (320–400 nm) and UV-B (280–320 nm) radiation causes damage to DNA and other biomolecules through reactions induced by different endogenous or exogenous photosensitizers. Lumazines are heterocyclic compounds present in biological systems as biosynthetic precursors and/or products of metabolic degradation. The parent and unsubstituted compound called lumazine (pteridine-2,4(1,3H)-dione; Lum) is able to act as photosensitizer through electron transfer-initiated oxidations. To get further insight into the mechanisms involved, we have studied in detail the oxidation of 2′-deoxyadenosine 5′-monophosphate (dAMP) photosensitized by Lum in aqueous solution. After UV-A or UV-B excitation of Lum and formation of its triplet excited state (³Lum*), three reaction pathways compete for the deactivation of the latter: intersystem crossing to singlet ground state, energy transfer to O₂, and electron transfer between dAMP and ³Lum* yielding the corresponding pair of radical ions (Lum˙⁻ and dAMP˙⁺). In the following step, the electron transfer from Lum˙⁻ to O₂ regenerates Lum and forms the superoxide anion (O₂˙⁻), which undergoes disproportionation into H₂O₂ and O₂. Finally dAMP˙⁺ participates in subsequent reactions to yield products. |
publishDate |
2012 |
dc.date.none.fl_str_mv |
2012 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Articulo http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
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http://sedici.unlp.edu.ar/handle/10915/130519 |
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http://sedici.unlp.edu.ar/handle/10915/130519 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/issn/1474-9092 info:eu-repo/semantics/altIdentifier/issn/1474-905X info:eu-repo/semantics/altIdentifier/doi/10.1039/c1pp05315a info:eu-repo/semantics/altIdentifier/pmid/22212735 |
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info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
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openAccess |
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http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
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