马脾铁蛋白铁核表层特性

The Properties of the Surface of Iron Core from Horse Spleen Ferritin

马脾铁蛋白整体铁核的磷酸盐与铁组成比是1:8±0.5,而表层组成比却是1:3±0.2,在pH7～10内,铁蛋白随着pH值递增,它以65±5磷原子/蛋白分子/pH速率释放无机磷酸盐和185±5铁原子/蛋白分子/pH速率释放铁,其磷酸盐与铁释放分子比也是1:3±0.5,推测这一过程是发生于铁核表层组成的变化,随着体系pH增加,氢氧根离子参与铁蛋白铁核组成,取代铁核表层某些磷铁成份,构成新的铁核表层组成,使铁蛋白氧化还原中间电位以-115mV/pH速率向负线性漂移。

Horse spleen ferritin contains, on the whole, an iron core of the compo-nent ratio 1:8±0. 5 of phosphate to iron, however, another one 1:3±0. 2 of phosphate to iron was known by the surface of iron core. Adjusting of pH from 7. 0 to 10. 0, the ferritin releases the phosphate and iron at the rate of 65 ±5 Piatoms/ferrittn/pH and 185 ±5 Fe atoms/ferritin/pH respectively, clearly showing that the ratio of releasing content 1:3±0. 5 of phosphate to iron from the ferritin was still found by the pH. The results suggest that the procedure descried above, maybe, occur on the surface composition change of iron core. With pH increasing, the hydroxyl ions would join the composition of iron core instead of a lot of phosphate and iron from the surface of iron core for making a new surface composition of iron core, which result in redox potentials of the ferritin as a liner shifted to negative at the rate of -115 mV/pH.