Soszyński M, Schuessler H
Department of Molecular Biophysics, University of Lódź.
Int J Radiat Biol. 1998 Feb;73(2):211-8. doi: 10.1080/095530098142608.
The effect of ethanol and formate radicals on the major proteins of human erythrocyte membranes has been investigated.
Human erythrocyte ghosts and of erythrocyte ghosts stripped of peripheric proteins were irradiated in phosphate buffer with 100 mmol dm(-3) ethanol or 100 mmol dm(-3) formate under N2 or N2O. The alterations of the proteins were investigated by SDS-polyacrylamide gel electrophoresis and high-performance gel permeation chromatography.
In contrast to previous results on ribonuclease and on serum albumin the ethanol radicals were found to have a higher efficiency to damage erythrocyte membrane proteins than the formate radicals. Spectrin (Bands 1 and 2) and capnophorin (Band 3) showed the highest radiation-induced loss of all membrane proteins. When cysteamine or dithiothreitol were added to the erythrocyte ghosts with a similar OH-scavenging capacity as ethanol or formate, no degradation or aggregation of the membrane proteins could be observed even after a dose as high as 1800 Gy.
The results of this study confirm the high radiosensitivity of spectrin and capnophorin to primary radicals. Similarly to soluble proteins, membrane-associated proteins are more significantly damaged by ethanol radicals than by formate radicals.
研究乙醇和甲酸根自由基对人红细胞膜主要蛋白质的影响。
在氮气或一氧化二氮环境下，用100 mmol dm(-3)乙醇或100 mmol dm(-3)甲酸在磷酸盐缓冲液中照射人红细胞血影及去除外周蛋白的红细胞血影。通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳和高效凝胶渗透色谱法研究蛋白质的变化。
与先前关于核糖核酸酶和血清白蛋白的结果相反，发现乙醇自由基比甲酸根自由基对红细胞膜蛋白的损伤效率更高。血影蛋白（带1和带2）和碳酸酐酶（带3）在所有膜蛋白中显示出最高的辐射诱导损失。当向红细胞血影中加入具有与乙醇或甲酸类似的羟基清除能力的半胱胺或二硫苏糖醇时，即使在高达1800 Gy的剂量后，也未观察到膜蛋白的降解或聚集。
本研究结果证实血影蛋白和碳酸酐酶对初级自由基具有高辐射敏感性。与可溶性蛋白类似，膜相关蛋白受乙醇自由基的损伤比受甲酸根自由基的损伤更显著。
