Suchergebnisse

[EN] The photochemistry of the DNA biomacromolecule is an issue of paramount importance as it is part of the etiology of skin cancer development, being ultraviolet sunlight radiation the most relevant environmental carcinogen. Herein, we demonstrate the potential of pterin, an endogenous compound, to form covalent adduct under UVA irradiation with a short thymine oligomer as well as with the whole DNA polymer. Our approach is based on the spectroscopic features of pterin, which allow, by monitoring specific absorption or emission wavelengths, the following-up of the covalent binding. The results are confirmed by HPLC coupled with mass spectrometry, revealing the attachment of one or two pterin units to the homothymine 5-mer oligonucleotide. Altogether the findings point toward the role of pterin as endogenous sensitizer and genotoxic compound. ; The present work was partially supported by Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET-Grant PIP 112-200901-0304), Agencia de Promocion Cientifica y Tecnologica (ANPCyT-Grant PICT-2012-0508), Universidad Nacional de La Plata (UNLP-Grant X712). Funding from the Programa CSIC de Cooperacion Cientifica para el Desarrollo (iCOOPLight project ref 20105CD0017) and Spanish Government (CTQ2015-70164-P) are gratefully acknowledged. S.E.R. thanks ANPCyT and CONICET for doctoral research fellowships. M.G.T thanks CONICET for postdoctoral fellowship. C.L. and A.H.T. are research members of CONICET. The authors thank Dr. Mariana Vignoni (INIFTA, CONICET) and Nathalie Martins-Froment of the Service Commun de Spectrometrie de Masse (FR2599), Universite de Toulouse III (Paul Sabatier) for their crucial contributions in mass spectrometry measurements. ; Estébanez, S.; Lorente, C.; Gaspar Tosato, M.; Miranda Alonso, MÁ.; Marín García, ML.; Lhiaubet, VL.; Thomas, AH. (2019). Photochemical formation of a fluorescent thymidine-pterin adduct in DNA. Dyes and Pigments. 160:624-632. https://doi.org/10.1016/j.dyepig.2018.08.024 ; S ; 624 ; 632 ; 160