鱼肝铁蛋白铁核表层接受电子能力的研究

采用直接电化学技术研究Hong鱼肝铁蛋白（Liver Ferritin of Dasyatis akajei,DALF）铁核表层接受还原电子的快慢速率和释放铁的动力学级数及规律。实验结果表明，在有氧环境下，DALF铁核表层以两相行为的方式快速地从铂金电极上获得还原电子且用于释放铁反应，其释放铁的还原电们分别为－125mV－375mV(vs.NHE,下同）。在控制还原电位为－200mV和－500mV的条件下，DALF铁核表层解放铁的速率分别为11．1Fe^3 /(DALF.min)和33．3Fe^3 (DALF.min），因而认为DALF从铂金电极接受电子和解放铁的速率快慢与还原电位高低有关。血红素不仅能络合于DALF蛋白壳（DALFh）上，而且还能加速DALFh释放铁的速率，但无法增加DALFh释放铁的总量。DALF铁核结构中的磷铁组成存在着非均匀性。DALF铁核表层磷铁结构具有接受来自于蛋白壳电子隧道提供的还原电子能力。

STUDIES ON CAPACITY OF PICKING UP ELECTRONS ON THE SURFACEOF IRON CORE FORM THE FERRITIN OF FISH LIVER

The fast and slow rates of the reduction electrons on the surface of iron core in liver ferritin of Dasyatis akajei (DALF) were studied by direct electrochemical technology which was also used to study the kinetic order and law of iron release. In aerobic environment, the experimental results showed that DALF, as a form of biphasic behavior, not only picked the electrons up from the platinum electrode, but also used them for iron releasing. Moreover, two-reduction potential of -125 mV and -375mV vs. NHE for iron release were determined. Using reduction potentials of -200 mV and- 500mV vs. NHE, two rates of iron release on the surface of iron core in DALF measured were 11.1 Fe3 /DALF/min and 33.3Fe3 /DALF/ min respectively, suggesting that the fast and slow rates of DALF picking the electrons up from the platinum electrode are tightly related to the reduction potentials. It was seen that the heme not only bound to the protein shell of DALF, but also accelerated the rate of iron release. However, the content of iron release was not increased by the heme in DALFh. The structure composition of phosphate and iron within the DALF core were heterogeneous. The surface structure of iron core in DALF is capable of picking up the electrons come from the electron tunnel of protein shell, which are used for iron releasing.