【摘要】 通过荧光猝灭实验和测定二聚体裂解程度的辐照实验 ,研究色氨酸 (Trp)及其二肽色氨酰苯丙氨酸 (Trp Phe)对cis syn型 1,3 二甲基胸腺嘧啶二聚体 (DMTD)的光敏化裂解作用 .结果表明 ,色氨酸及其二肽在较强光 (λ >2 90nm)辐照下 ,主要通过双光子电离生成的水合电子 (e-aq)导致二聚体裂解 ,其次 ,通过激发单重态与二聚体间的电子转移导致二聚体裂解 .另外一导致二聚体裂解的可能途径 :色氨酸残基激发三重态与二聚体间的电子转移光敏化二聚体裂解 .更多还原

【Abstract】 Photosensitized splitting of cis - syn 1,3-dimethylthymine dimer by tryptophan and its peptides (Trp-Phe) was studied based on the fluorescence quenching experiments and irradiation experiments determining the splitting percentage of the dimer. It was revealed that 1,3-dimethylthymine dimer was mainly splitted by e -_ aq resulted from two-photon ionization of Trp and its peptides under irradiation with light ( λ >290 nm). Moreover, the excited singlet state of Trp and its peptides can transfer an electron to the dimer and make it splitted. In addition, the excited triplet state of Trp can also transfer an electron to the dimer and make it splitted.更多还原