The role of the maturase HydG in [FeFe]-hydrogenase active site synthesis and assembly
The role of the maturase HydG in [FeFe]-hydrogenase active site synthesis and assembly
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DOI：
10.1016/j.febslet.2009.01.004
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发表时间：
2009-02-04
期刊：
影响因子：
3.5
通讯作者：
Fontecave, Marc
中科院分区：
文献类型：
--
作者：
Pilet, Eric;Nicolet, Yvain;Fontecave, Marc
[FeFe]-氢化酶通过由三个CO和两个CN配体组成的独特的二铁活性位点和非蛋白质SCH 2XCH 2S（X = N或O）二硫代硫酸盐桥催化质子/氢相互转化。位点组装需要两种“自由基-S-腺苷甲硫氨酸（SAM或腺苷甲硫氨酸）”铁-硫酶，HydE和HydG，以及一种GTdR，HydF。HydG和ThiH（一种将酪氨酸切割成对甲酚和脱氢甘氨酸的自由基SAM酶）之间的序列同源性，以及HydG催化的类似切割反应的发现表明了氢化酶成熟的机制。在这里，我们建议，HydG是专门参与的二硫纶配体的合成，与两个酪氨酸衍生的脱氢甘氨酸作为前体沿着与HydG的[FeS]簇作为电子穿梭和源的硫原子。(c)2009年欧洲生物化学学会联合会。Elsevier B. V.出版，保留所有权利。
[FeFe]-hydrogenases catalyze the protons/hydrogen interconversion through a unique di-iron active site consisting of three CO and two CN ligands, and a non-protein SCH2XCH2S (X = N or O) dithiolate bridge. Site assembly requires two "Radical-S-adenosylmethionine (SAM or AdoMet)" iron-sulfur enzymes, HydE and HydG, and one GTPase, HydF. The sequence homology between HydG and ThiH, a Radical-SAM enzyme which cleaves tyrosine into p-cresol and dehydroglycine, and the finding of a similar cleavage reaction catalyzed by HydG suggests a mechanism for hydrogenase maturation. Here we propose that HydG is specifically involved in the synthesis of the dithiolate ligand, with two tyrosine-derived dehydroglycines as precursors along with an [FeS] cluster of HydG functioning both as electron shuttle and source of the sulfur atoms. (c) 2009 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.