Model Studies of DNA Photorepair: Reduction Potentials of Thymine and Cytosine Cyclobutane Dimers Measured by Fluorescence Quenching

摘要

The interactions of various pyrimidines (1, 3-dimethylthymine, DMT, 1, 3-bis(N~4, N~4-dimethylcytosin-1- yl)propane, DMC) and their corresponding cis-syn cyclobutane dimmers (DMTD and DMCD)with a series of excited- state electron donors were examined with the goal of understanding the energetics and mechanism of UV repair by DNA photolyase. For each substrate there is a good correlation between the excited state oxidation potential(E_ox) and the quenching rate constant (Kq).