Oriented immobilization of Desulfovibrio gigas hydrogenase onto carbon electrodes by covalent bonds for nonmediated oxidation of H2
Oriented immobilization of Desulfovibrio gigas hydrogenase onto carbon electrodes by covalent bonds for nonmediated oxidation of H2
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DOI：
10.1021/ja0554312
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发表时间：
2005-11-23
影响因子：
15
通讯作者：
De Lacey, AL
中科院分区：
文献类型：
--
作者：
Rüdiger, O;Abad, JM;De Lacey, AL
氢化酶与用 4-氨基苯基单层修饰的热解石墨边缘电极共价结合的方向可以在固定步骤期间通过静电相互作用进行调节。在低离子强度下，当电极表面的氨基大部分被质子化时，氢化酶被固定在其 4Fe4S 簇周围的带负电区域，更靠近面向电极的蛋白质表面。这允许固定化氢化酶和电极之间发生直接电子转移，这是通过在 H2 底物存在下测量的强催化电流观察到的。因此，产生了非常稳定的酶电极，可以催化非介导的 H2 氧化。
The orientation of hydrogenase bound covalently to a pyrolytic graphite edge electrode modified with a 4-aminophenyl monolayer can be modulated via electrostatic interactions during the immobilization step. At low ionic strength and when the amino groups of the electrode surface are mostly protonated, the hydrogenase is immobilized with the negatively charged region that surrounds its 4Fe4S cluster nearer to the protein surface facing the electrode. This allows direct electron transfer between the immobilized hydrogenase and the electrode, which is observed by the strong catalytic currents measured in the presence of the H2substrate. Therefore, a very stable enzymatic electrode is produced that catalyzes nonmediated H2oxidation.