Barth C, Stark G
Fakultät für Biologie, Universität Konstanz, F.R.G.
Biochim Biophys Acta. 1991 Jul 1;1066(1):54-8. doi: 10.1016/0005-2736(91)90249-8.
The conductance induced by the channel-forming peptide gramicidin A in lipid membranes is reduced by many orders of magnitude on exposure of the membrane and its aqueous environment to ionizing radiation. This results from an interaction of free radicals of water radiolysis with the tryptophan residues of gramicidin A. The sensitivity of the ion channels towards irradiation is strongly reduced in the presence of either vitamin E or of highly unsaturated lipids. An increase of the D37 dose up to a factor of 50 was found. The phenomena are interpreted via a reduction of the effective concentration of free radicals (such as OH.) in the membrane by reaction with unsaturated fatty acid residues or with vitamin E.
在脂质膜及其水环境暴露于电离辐射时，由通道形成肽短杆菌肽A诱导的电导降低了许多个数量级。这是由于水辐射分解产生的自由基与短杆菌肽A的色氨酸残基相互作用所致。在维生素E或高度不饱和脂质存在的情况下，离子通道对辐射的敏感性会大大降低。发现D37剂量增加了高达50倍。这些现象可通过与不饱和脂肪酸残基或维生素E反应来降低膜中自由基（如OH.）的有效浓度来解释。
