Crystal structure of Escherichia coli SufC, an ABC-type ATPase component of the SUF iron-sulfur cluster assembly machinery
Crystal structure of Escherichia coli SufC, an ABC-type ATPase component of the SUF iron-sulfur cluster assembly machinery
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DOI：
10.1016/j.febslet.2005.11.058
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发表时间：
2006-01-09
期刊：
影响因子：
3.5
通讯作者：
Takahashi, Y
中科院分区：
文献类型：
--
作者：
Kitaoka, S;Wada, K;Takahashi, Y
SufC 是 SUF 机器的 ATP 酶组件，参与 Fe-S 簇的生物合成。为了深入了解该蛋白质的功能，我们以 2.5 A 分辨率测定了大肠杆菌 SufC 的晶体结构。尽管整体结构与 ABC-ATP-ase（ABC 转运蛋白的核苷酸结合域）相似，但仍观察到一些关键差异。 Glu171 是参与 ATP 水解的不变残基，它从核苷酸结合袋中旋转出来，与 Lys152 形成 SufC 特异性盐桥。由于这种盐桥，Glu171 后面的 D 环被翻转到分子表面，这可能会在空间上抑制活性二聚体的形成。因此，盐桥可能在调节 ATP 酶活性和防止浪费的 ATP 水解中发挥关键作用。此外，SufC 表面具有独特的 Q 环结构，可形成其伴侣蛋白 SufB 和/或 SufD 的结合位点。 (c) 2005 年欧洲生化学会联合会。由 Elsevier B.V. 出版。保留所有权利。
SufC is an ATPase component of the SUF machinery, which is involved in the biosynthesis of Fe-S clusters. To gain insight into the function of this protein, we have determined the crystal structure of Escherichia coli SufC at 2.5 A resolution. Despite the similarity of the overall structure with ABC-ATP-ases (nucleotide-binding domains of ABC transporters), some key differences were observed. Glu171, an invariant residue involved in ATP hydrolysis, is rotated away from the nucleotidebinding pocket to form a SufC-specific salt bridge with Lys152. Due to this salt bridge, D-loop that follows Glu171 is flipped out to the molecular surface, which may sterically inhibit the formation of an active dimer. Thus, the salt bridge may play a critical role in regulating ATPase activity and preventing wasteful ATP hydrolysis. Furthermore, SufC has a unique Q-loop structure on its surface, which may form a binding site for its partner proteins, SufB and/or SufD. (c) 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.