Crystal structure of formate dehydrogenase H: Catalysis involving Mo, molybdopterin, selenocysteine, and an Fe4S4 cluster
Crystal structure of formate dehydrogenase H: Catalysis involving Mo, molybdopterin, selenocysteine, and an Fe4S4 cluster
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DOI：
10.1126/science.275.5304.1305
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发表时间：
1997-02-28
期刊：
影响因子：
56.9
通讯作者：
Sun, PD
中科院分区：
文献类型：
--
作者：
Boyington, JC;Gladyshev, VN;Sun, PD
来自大肠杆菌的甲酸脱氢酶H含有硒代半胱氨酸（SeCys）、钼、两个二氢蝶呤鸟嘌呤二核苷酸（MGD）辅因子和在活性位点处的Fe4S4簇，并且催化甲酸的双电子氧化为二氧化碳。甲酸脱氢酶H的氧化[Mo（VI），Fe4S4（ox）]形式（有和没有结合的抑制剂）和还原[Mo（IV），Fe4S4（red）]形式的晶体结构已经确定，揭示了钼直接与硒和两种MGD辅因子配位的四域α β结构。这些结构表明，直接涉及SeCys（140）和His（141）的质子提取和钼，异蝶呤，赖氨酸（44），和Fe4S4簇的电子转移的反应机制。
Formate dehydrogenase H from Escherichia coli contains selenocysteine (SeCys), molybdenum, two molybdopterin guanine dinucleotide (MGD) cofactors, and an Fe4S4 cluster at the active site and catalyzes the two-electron oxidation of formate to carbon dioxide. The crystal structures of the oxidized [Mo(VI), Fe4S4(ox)] form of formate dehydrogenase H (with and without bound inhibitor) and the reduced [Mo(IV), Fe4S4(red)] form have been determined, revealing a four-domain alpha beta structure with the molybdenum directly coordinated to selenium and both MGD cofactors. These structures suggest a reaction mechanism that directly involves SeCys(140) and His(141) in proton abstraction and the molybdenum, molybdopterin, Lys(44), and the Fe4S4 cluster in electron transfer.