Cannistraro S, van de Vorst A
Biochim Biophys Acta. 1977 Jan 20;474(2):173-9. doi: 10.1016/0005-2787(77)90191-5.
At pH values 5 and 9, the influence of cysteine, cystine, 3-mercaptopropionic acid and S-methylcysteine on the induction of H-adduct radicals in thymidine and thymidine 5'-monophosphate photosensitized by proflavin is investigated. The results obtained indicate that efficient protection is given when the electrostatic interactions between the charged groups of the molecules present allow the close proximity of a thiol or a disulfide bridge and the proflavin - DNAs complex constituent. The scheme proposed for the mechanism involves the capture by the protector of an electron or a proton, indispensable intermediates in the formation of the H-adduct radicals.
在pH值为5和9时，研究了半胱氨酸、胱氨酸、3-巯基丙酸和S-甲基半胱氨酸对由黄素引发的胸苷和5'-单磷酸胸苷光致敏过程中H-加合物自由基诱导的影响。所得结果表明，当存在的分子带电基团之间的静电相互作用使硫醇或二硫键与黄素-DNA复合物成分紧密接近时，能提供有效的保护作用。所提出的作用机制方案涉及保护剂捕获电子或质子，这是形成H-加合物自由基过程中不可或缺的中间体。
