Photoinduced charge separation and DNA self-repair depend on sequence directionality and stacking pattern
Corinna L. Kufner, Sarah Crucilla, Dian Ding, Petr Stadlbauer, Jiřı́ Šponer, Jack W. Szostak, Dimitar Sasselov, Rafał Szabla
Abstract
˙ charge transfer state in the dominant conformers of the T[double bond, length as m-dash]TAG tetramer. These conformational differences also hinder alternative photorelaxation pathways of the T[double bond, length as m-dash]TAG tetranucleotide, which otherwise compete with the sequential electron transfer mechanism responsible for CPD self-repair. Overall, we demonstrate that photoinduced electron transfer is strongly dependent on conformation and the availability of alternative photodeactivation mechanisms. This knowledge can be used in the identification and prediction of canonical and modified DNA sequences exhibiting efficient electron transfer. It also further contributes to our understanding of DNA self-repair and its potential role in the photochemical selection of the most photostable sequences on the early Earth.