Structural and Biochemical Characterizations of Methanoredoxin from Methanosarcina acetivorans, a Glutaredoxin-Like Enzyme with Coenzyme M-Dependent Protein Disulfide Reductase Activity.
Structural and Biochemical Characterizations of Methanoredoxin from Methanosarcina acetivorans, a Glutaredoxin-Like Enzyme with Coenzyme M-Dependent Protein Disulfide Reductase Activity.
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来自 Methanosarcina acetivorans 的甲烷氧还蛋白的结构和生化特征，这是一种具有辅酶 M 依赖性蛋白二硫键还原酶活性的谷氧还蛋白样酶。
DOI：
10.1021/acs.biochem.5b00823
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发表时间：
2016
期刊：
影响因子：
2.9
通讯作者：
Ferry,JamesG
中科院分区：
文献类型：
--
作者：
Yenugudhati,Deepa;Prakash,Divya;Kumar,AdepuK;Kumar,RSivaSai;Yennawar,NeelaH;Yennawar,HemantP;Ferry,JamesG
谷氧还蛋白（GRX）是原核生物中丰富的巯基-二硫键氧化还原酶，尽管对这些酶的结构域了解甚少。除了谷胱甘肽作为还原剂之外，细菌领域的许多特征GRX还利用多种低分子量硫醇。本文报道了产乙酸甲烷八叠球菌（Methanosarcina acetivorans）中一种名为甲烷氧还蛋白（methanoredoxin，MRX）的GRX样蛋白的生化和结构特性。MRX利用辅酶M（CoMSH）作为胰岛素二硫还原酶活性的还原剂，这增加了原核生物中巯基保护剂的多样性。M. acetivorans显示CoMS-SCoM还原酶活性，补充了MRX的CoMSH依赖性活性。晶体结构显示出典型的硫氧还蛋白-谷氧还蛋白折叠，其包括围绕四个反平行β-折叠的三个α-螺旋。表面上的口袋包含CVWC基序，识别具有类似于GRX的结构的活性位点。虽然它是溶液中的单体，但晶格中有四个单体呈二聚体的二聚体排列。在每个单体的活性位点内发现镉离子。两个这样的离子稳定N-末端尾部和二聚体界面。我们的建模研究表明，CoMSH和谷胱甘肽（GSH）结合到MRX的活性位点，类似于GRX中GSH的结合，尽管结合基序的氨基酸组成存在差异。结合我们的生物信息学分析，结果表明，MRX代表了一类GRX样酶存在于甲烷生产菌的多样性。
Glutaredoxins (GRXs) are thiol–disulfide oxidoreductases abundant in prokaryotes, although little is understood of these enzymes from the domainArchaea. The numerous characterized GRXs from the domainBacteriautilize a diversity of low-molecular-weight thiols in addition to glutathione as reductants. We report here the biochemical and structural properties of a GRX-like protein named methanoredoxin (MRX) fromMethanosarcina acetivoransof the domainArchaea. MRX utilizes coenzyme M (CoMSH) as reductant for insulin disulfide reductase activity, which adds to the diversity of thiol protectants in prokaryotes. Cell-free extracts ofM. acetivoransdisplayed CoMS-SCoM reductase activity that complements the CoMSH-dependent activity of MRX. The crystal structure exhibits a classic thioredoxin-glutaredoxin fold comprising three α-helices surrounding four antiparallel β-sheets. A pocket on the surface contains a CVWC motif, identifying the active site with architecture similar to GRXs. Although it is a monomer in solution, the crystal lattice has four monomers in a dimer of dimers arrangement. A cadmium ion is found within the active site of each monomer. Two such ions stabilize the N-terminal tails and dimer interfaces. Our modeling studies indicate that CoMSH and glutathione (GSH) bind to the active site of MRX similar to the binding of GSH in GRXs, although there are differences in the amino acid composition of the binding motifs. The results, combined with our bioinformatic analyses, show that MRX represents a class of GRX-like enzymes present in a diversity of methane-producingArchaea.