羟基肉桂酸衍生物对组蛋白 H3 辐射保护的 ESR 研究  

ESR STUDY ON RADIATION PROTECTION OF HISTONE H3 BY HYDROXYCINNAMIC ACID DERIVATIVES

作　　者：林维真[1,2] 屠铁城[1,2] 董继荣[1,2] 姚思德[1,2] 张加山[1,2] 林念芸[1,2] 

机构地区：[1]中国科学院辐射化学研究开放实验室 [2]上海原子核研究所

出　　处：《辐射研究与辐射工艺学报》1997年第4期210-216,共7页Journal of Radiation Research and Radiation Processing

基　　金：国家自然科学基金

摘　　要：应用ＥＳＲ波谱模拟解析法，研究了７７Ｋγ辐射引发羟基肉桂酸衍生物与组蛋白Ｈ３的二元分子复合体系两组分间的电子转移过程。在解析二元复合体系ＥＳＲ波谱的基础上，计算了二元分子复合体系两组分摩尔比不同的一系列复合体系的自旋转移比Ｒｓｃ。研究发现Ｒｓｃ与复合体系的摩尔比呈良好的线性关系，这表明羟基肉桂酸衍生物具有较强的夺取蛋白质肽链酰胺羰基阴离子自由基电子和修复蛋白质辐射损伤的能力，这与用羟基肉桂酸衍生物通过电荷转移对生物大分子辐射损伤的保护、修复机理的前期研究结果相符。在研究了辐射引发的组蛋白Ｈ３咖啡酸分子复合体系自旋转移比的ｐＨ效应基础上，阐明了分子复合体系内蛋白质肽链酰胺羰基与咖啡酸间的氢键是实现体系内分子间电子转移的主要通道。Radiation induced electron transfer between histone H3 and some hydroxycinnamic acid derivatives within binary molecular aggregates has been in vestigated by means of resolution and simulation of ESR spectra from those aggregates γ irradiated and recorded at 77K, respectively The excellent linear relationships, which were made on the basis of simulation of composite ESR spectra relevant to those binary aggregates with various molar ratios of the two components, between spin transfer ratios (Rsc) and molar ratios (r) of the aggregates indicate that those hydroxycinnamic acid derivatives have effective potential for repair of the radiation damaged protein by abstracting electrons on peptide carbonyl radical anions in protein These results are in good accord with our previous studies on radiation protection of DNA and proteins via charge transfer from the damaged biomolecules to hydroxycinnamic acid derivatives The hydrogen bond formed between peptide carbonyl in protein and phenolic hydroxyl of hydroxycinnamic acids within the aggregates has been illustrated as the major pathway for electron transfer from H3 to caffeic acid hased upon pH dependence on the linear relationship between Rsc and r of irradiated histone H3caffeic acid aggregates

关 键 词：组蛋白 咖啡酸 芥子酸 辐射保护 酚羟基自由基 

分 类 号：R979.6[医药卫生—药品] Q691.2[医药卫生—药学]