Schuessler H, Davies J V, Scherbaum W, Jung E
Int J Radiat Biol Relat Stud Phys Chem Med. 1986 Nov;50(5):825-39. doi: 10.1080/09553008614551251.
Radiation-induced reactions of hydrated electrons, formate- and ethanol radicals with ribonuclease were studied by pulse radiolysis and by electrophoresis. Initially formate radicals react rapidly and very specifically with the disulphide bonds of ribonuclease. This reaction leads to aggregation by intermolecular S-S-interchange, the process being more effective at pH 4, since formation and decay of S-S-.-radical anions increases with decreasing pH. With high doses additional unreducible aggregates are formed. Radical formation at the positively charged histidine residues seems to be involved. Hydrated electrons do not react as selectively as the formate radicals, but with several sites in native ribonuclease. Thus with low doses unreducible aggregates are formed. Electrophoresis shows that reaction of the electrons causes fragmentation of the peptide chain, when OH-radicals are scavenged. Very weak transient spectra and very little degradation result on reaction of ethanol radicals with ribonuclease.
通过脉冲辐解和电泳研究了水合电子、甲酸根自由基和乙醇自由基与核糖核酸酶的辐射诱导反应。最初，甲酸根自由基与核糖核酸酶的二硫键迅速且非常特异性地反应。该反应通过分子间的S-S交换导致聚集，此过程在pH 4时更有效，因为S-S-·自由基阴离子的形成和衰减随pH降低而增加。高剂量时会形成额外的不可还原聚集体。似乎涉及在带正电荷的组氨酸残基处形成自由基。水合电子不像甲酸根自由基那样具有选择性反应，而是与天然核糖核酸酶中的多个位点反应。因此，低剂量时会形成不可还原聚集体。电泳表明，当清除OH自由基时，电子的反应会导致肽链断裂。乙醇自由基与核糖核酸酶反应时产生非常微弱的瞬态光谱和极少的降解。
