Electrochemical Investigations of the Mechanism of Assembly of the Active-Site H-Cluster of [FeFe]-Hydrogenases.
Electrochemical Investigations of the Mechanism of Assembly of the Active-Site H-Cluster of [FeFe]-Hydrogenases.
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[FeFe]-氢化酶活性位点 H 簇组装机制的电化学研究。
DOI：
10.1021/jacs.6b09366
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发表时间：
2016
影响因子：
15
通讯作者：
Megarity CF
中科院分区：
文献类型：
--
作者：
Megarity CF
蛋白质膜电化学（PFE）已被用于研究[FeFe]-氢化酶的络合物6Fe活性位点（称为h簇）从其前体（已在宿主内协调的[4Fe-4S]结构域）组装。而2Fe结构域则表现为一种由额外CO稳定的合成水溶性配合物。PFE不仅可以通过电极电位控制氧化还原状态，而且酶的固定化状态也有助于控制极低浓度的2Fe配合物。结果表明，来自莱茵衣藻的CrHydA1酶和来自巴氏梭菌的cpi酶虽然在大小和结构上有很大的差异，但两种酶非常相似。组装开始于34价电子2Fe配合物与载子-[4Fe-4S]酶的紧密结合，远早于速率决定步骤。前驱体被困在高度还原的条件下（< - 0.5 V vs SHE），这阻止了[4Fe-4S]和2Fe域的融合（通过半胱氨酸- s），因为直接产物将过于富含电子。放松这个条件允许转换为活动h簇。分子内步骤与生物h簇成熟的最后阶段有关。
Protein film electrochemistry (PFE) has been used to study the assembly of the complex 6Fe active site of [FeFe]-hydrogenases (known as the H-cluster) from its precursorsthe [4Fe-4S] domain that is already coordinated within the host, and the 2Fe domain that is presented as a synthetic water-soluble complex stabilized by an additional CO. Not only does PFE allow control of redox states via the electrode potential but also the immobilized state of the enzyme facilitates control of extremely low concentrations of the 2Fe complex. Results for two enzymes,CrHydA1 fromChlamydomonas reinhardtiiandCpI fromClostridium pasteurianum, are very similar, despite large differences in size and structure. Assembly begins with very tight binding of the 34-valence electron 2Fe complex to the apo-[4Fe-4S] enzyme, well before the rate-determining step. The precursor is trapped under highly reducing conditions (<−0.5 V vs SHE) that prevent fusion of the [4Fe-4S] and 2Fe domains (via cysteine-S) since the immediate product would be too electron-rich. Relaxing this condition allows conversion to the active H-cluster. The intramolecular steps are relevant to the final stage of biological H-cluster maturation.
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影响因子：
21.8
作者：
Fourmond, Vincent;Greco, Claudio;Leger, Christophe
通讯作者：
Leger, Christophe
脱硫弧菌 [FeFe]-氢化酶催化状态和抑制状态之间相互转化的电化学研究。
影响因子：
15
作者：
A. Parkin;C. Cavazza;J. Fontecilla;F. Armstrong
通讯作者：
F. Armstrong
影响因子：
15
作者：
Goldet, Gabrielle;Brandmayr, Caterina;Armstrong, Fraser A.
通讯作者：
Armstrong, Fraser A.
影响因子：
3.7
作者：
Kuchenreuther JM;Grady-Smith CS;Bingham AS;George SJ;Cramer SP;Swartz JR
通讯作者：
Swartz JR
DOI：
10.1073/pnas.1204770109
发表时间：
2012-07-17
影响因子：
11.1
作者：
Hexter, Suzannah V.;Grey, Felix;Armstrong, Fraser A.
通讯作者：
Armstrong, Fraser A.