VIP (very important paper): Photosensitization of DNA by a 5-Methyl-2-Pyrimidone Deoxyribonucleoside: The (6–4) Photoproduct as a Trojan Horse
Victoria Vendrell-Criado, Gemma M. Rodríguez-Muñiz, M. Consuelo Cuquerella, Virginie Lhiaubet-Vallet,* and Miguel A. Miranda*
An interesting feature of (6–4) photoproducts is their relatively long-wavelength absorption, which could extend the active fraction of sunlight. Surprisingly, their potential role as intrinsic DNA photosensitizers has not been addressed yet. This appealing question has been tackled here by model studies with a 5-methyl-2-pyrimidone deoxyribonucleoside, the main chromophore of (6–4) photoproducts. The results reveal photosensitized formation of oxidation products and cyclobutane thymine dimers. Overall, this raises the issue of a possible aggravation of the photomutagenicity of (6–4) lesions, acting as Trojan horses.