Simpson J A, Narita S, Gieseg S, Gebicki S, Gebicki J M, Dean R T
Heart Research Institute, Camperdown, Sydney, N.S.W., Australia.
Biochem J. 1992 Mar 15;282 ( Pt 3)(Pt 3):621-4. doi: 10.1042/bj2820621.
We have demonstrated two novel reactive species on radical-modified proteins which are relatively long-lived, one oxidizing and one reducing. The two species are reactive with critical biological components, and so may be of physiological and pathological importance. The oxidizing species, which have been identified as protein hydroperoxides, can consume key cellular reductants, such as ascorbate and glutathione. The reducing species can act on both free and metalloprotein forms of copper and iron ions, which participate in radical generation. These findings suggest that proteins may act as traps for the chemical energy released by free radicals, with the capacity to pass it on to other molecules. The long-lived nature of both the reactive moieties indicates that they may be able to diffuse and transfer damaging reactions to distant sites.
我们已在自由基修饰的蛋白质上证实了两种相对长寿命的新型活性物种，一种具有氧化性，一种具有还原性。这两种物种能与关键生物成分发生反应，因此可能具有生理和病理意义。已被鉴定为蛋白质氢过氧化物的氧化性物种可消耗关键细胞还原剂，如抗坏血酸和谷胱甘肽。还原性物种可作用于铜离子和铁离子的游离形式及金属蛋白形式，而这些离子参与自由基的生成。这些发现表明，蛋白质可能充当自由基释放的化学能量的捕获器，并能够将其传递给其他分子。这两种反应性部分的长寿命特性表明它们或许能够扩散并将损伤反应转移至远处位点。
