SufE transfers sulfur from SufS to SufB for iron-sulfur cluster assembly
SufE transfers sulfur from SufS to SufB for iron-sulfur cluster assembly
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DOI：
10.1074/jbc.m608555200
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发表时间：
2007-05-04
影响因子：
4.8
通讯作者：
Outten, F. Wayne
中科院分区：
文献类型：
--
作者：
Layer, Gunhild;Gaddam, S. Aparna;Outten, F. Wayne
铁硫簇是大多数生物体中代谢、调节和应激反应蛋白的关键金属辅因子。这些簇的独特性质使它们容易受到铁饥饿或氧化应激的破坏。在应力条件下，铁和硫都可以被扰动，导致Fe-S团簇缺陷。细菌和高等植物在逆境下都有一个专门的Fe-S簇生物合成系统，即Suf途径。在大肠杆菌中，Suf途径由六种功能仅部分表征的蛋白质组成。在这里，我们描述了SufS和SufE蛋白如何与SufBCD蛋白复合物相互作用，以促进半胱氨酸的硫释放和Fe-S簇组装的捐赠。先前表明，半胱氨酸脱硫酶SufS向硫转移蛋白SufE提供硫。我们在这里发现，SufE反过来与SufB蛋白相互作用，将硫转移到该蛋白。只有当SufC存在时才发生相互作用。此外，SufB可以作为一个网站的Fe-S簇组装在Suf系统。这提供了第一个证据的一个新的网站Fe-S簇组装在SufBCD复杂。
Iron-sulfur (Fe-S) clusters are key metal cofactors of metabolic, regulatory, and stress response proteins in most organisms. The unique properties of these clusters make them susceptible to disruption by iron starvation or oxidative stress. Both iron and sulfur can be perturbed under stress conditions, leading to Fe-S cluster defects. Bacteria and higher plants contain a specialized system for Fe-S cluster biosynthesis under stress, namely the Suf pathway. In Escherichia coli the Suf pathway consists of six proteins with functions that are only partially characterized. Here we describe how the SufS and SufE proteins interact with the SufBCD protein complex to facilitate sulfur liberation from cysteine and donation for Fe-S cluster assembly. It was previously shown that the cysteine desulfurase SufS donates sulfur to the sulfur transfer protein SufE. We have found here that SufE in turn interacts with the SufB protein for sulfur transfer to that protein. The interaction occurs only if SufC is present. Furthermore, SufB can act as a site for Fe-S cluster assembly in the Suf system. This provides the first evidence of a novel site for Fe-S cluster assembly in the SufBCD complex.