How the presence of three iron binding sites affects the iron storage function of the ferritin (EcFtnA) of Escherichia coli

FEBS Letters

Zhao, Zhongwei¹  Quail, Michael A¹  Guest, John R¹  Treffry, Amyra¹  Harrison, Pauline M¹ 

[1] The Krebs Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK

关键词: Ferritin;    Dinuclear centre;    Iron oxidation;    Iron metabolism;   

DOI  :  10.1016/S0014-5793(98)00867-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The iron storage proteins, ferritins, are found in all organisms which use iron. Here iron storage processes in the Escherichia coli ferritin (EcFtnA) are compared with those in human H-type ferritin (HuHF). Both proteins contain dinuclear iron centres that enable the rapid oxidation of 2 Fe(II) by O₂. The presence of a third iron binding site in EcFtnA, although not essential for fast oxidation, causes the O₂/Fe ratio to increase from 2 to 3–4. In EcFtnA the rate of iron oxidation falls markedly after the oxidation of 48 Fe(II) atoms/molecule probably because some of it remains at the oxidation site. However a compensatory physiological advantage is conferred because this iron is more readily available to meet the cell's needs.

【 授权许可】

Unknown