一个对铁氧化还原蛋白与铁氧化还原蛋白-NADP(+)还原酶之间高效电子转移至关重要的铁氧化还原蛋白精氨酸-谷氨酸对。

A ferredoxin Arg-Glu pair important for efficient electron transfer between ferredoxin and ferredoxin-NADP(+) reductase.

作者信息

Teshima Keizo, Fujita Shinobu, Hirose Syuuichi, Nishiyama Daisuke, Kurisu Genji, Kusunoki Masami, Kimata-Ariga Yoko, Hase Toshiharu

机构信息

Faculty of Integrated Arts and Sciences, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima 739-8521, Japan.

出版信息

FEBS Lett. 2003 Jul 10;546(2-3):189-94. doi: 10.1016/s0014-5793(03)00559-3.

DOI:10.1016/s0014-5793(03)00559-3

PMID:12832038

Abstract

In order to elucidate the importance of a ferredoxin (Fd) Arg-Glu pair involved in dynamic exchange from intra- to intermolecular salt bridges upon complex formation with ferredoxin-NADP(+) oxidoreductase (FNR), Equisetum arvense FdI and FdII were investigated as normal and the pair-lacking Fd, respectively. The FdI mutant lacking this pair was unstable and rapidly lost the [2Fe-2S] cluster. The catalytic constant (k(cat)) of the electron transfer for FdI is 5.5 times that for FdII and the introduction of this pair into FdII resulted in the increase of k(cat) to a level comparable to that for FdI, demonstrating directly that the Arg-Glu pair is important for efficient electron transfer between Fd and FNR.

摘要

为了阐明在与铁氧化还原蛋白 - NADP(+)氧化还原酶（FNR）形成复合物时，参与分子内盐桥到分子间盐桥动态交换的铁氧化还原蛋白（Fd）精氨酸 - 谷氨酸对的重要性，分别研究了问荆FdI和FdII，其中FdI为正常的，FdII为缺乏该对氨基酸的Fd。缺乏该对氨基酸的FdI突变体不稳定，[2Fe - 2S]簇迅速丢失。FdI电子转移的催化常数（k(cat)）是FdII的5.5倍，将该对氨基酸引入FdII导致k(cat)增加到与FdI相当的水平，直接证明了精氨酸 - 谷氨酸对对于Fd和FNR之间的高效电子转移很重要。