Mechanism of UV-Induced Formation of Dewar Lesions in DNA

摘要

Living organisms exposed to sunlight are constantly challenged by the formation of UV-induced lesions in DNA, which induce cell death and cause mutations. UV irradiation of TpT and TpC sequences leads to the formation of two primary lesions, namely cyclobutane-pyrimidine dimers (CPD) and (6-4) lesions, as depicted in Scheme 1. These (6-4) lesions possess an additional absorption at λ_(max) = 320 nm and rearrange to give Dewar valence isomers.