鱼肝铁蛋白铁核表层接受电子能力的研究  

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

作　　者：黄河清[1] 林庆梅[2] 罗大民[1] 朱斌琳[1] 

机构地区：[1]厦门大学生命科学学院细胞生物学与肿瘤细胞工程教育部重点实验室 [2]厦门大学海洋与环境科学教育部重点实验室,福建厦门361005

出　　处：《生物物理学报》2001年第4期754-760,共7页Acta Biophysica Sinica

基　　金：国家自然科学基金资助项目 (49876027);教育部高等学校骨干教师资助计划基金;海洋与环境科学教育部重点实验室基金资助项目

摘　　要：采用直接电化学技术研究鱼肝铁蛋白 (LiverFerritinofDasyatisakajei,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,其释放铁的还原电位分别为 -125mV和 -375mV(vs.NHE,下同 )。在控制还原电位为 -200mV和 -500mV的条件下,DALF铁核表层释放铁的速率分别为11.1Fe3 +/(DALF·min)和33.3Fe3 +/(DALF·min),因而认为DALF从铂金电极接受电子和释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。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.

关 键 词：Hong鱼肝铁蛋白 直接电化学 释放铁 铁核结构 释放铁动力学 电子传递 

分 类 号：Q513[生物学—生物化学] Q617