A redox hydrogel protects hydrogenase from high-potential deactivation and oxygen damage
A redox hydrogel protects hydrogenase from high-potential deactivation and oxygen damage
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DOI：
10.1038/nchem.2022
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发表时间：
2014-09-01
期刊：
影响因子：
21.8
通讯作者：
Lubitz, Wolfgang
中科院分区：
文献类型：
--
作者：
Plumere, Nicolas;Ruediger, Olaf;Lubitz, Wolfgang
氢酶是自然界中有效的催化剂，既可以通过氧化分子氢来产生能量，也可以通过还原质子来产生氢。然而，它们对O-2的敏感性和在高电位下的失活限制了它们在实际器件中的应用，如燃料电池。在这里，我们展示了将对O-2敏感的氢酶整合到专门设计的基于紫精的氧化还原聚合物中，以保护酶免受O-2损伤和高电位失活。聚合物结合紫精部分之间的电子转移控制氢酶活性部位的电势，从而使酶免受过度氧化压力的影响。在催化循环下，氢氧化反应提供的电子诱导紫精催化聚合物表面的O-2还原，从而提供对O-2的自激活保护。在阳极限制条件下，使用基于氧-2敏感氢酶和H-2/O-2混合饲料的单室生物燃料电池展示了这种串联保护的优点。
Hydrogenases are nature's efficient catalysts for both the generation of energy via oxidation of molecular hydrogen and the production of hydrogen via the reduction of protons. However, their O-2 sensitivity and deactivation at high potential limit their applications in practical devices, such as fuel cells. Here, we show that the integration of an O-2-sensitive hydrogenase into a specifically designed viologen-based redox polymer protects the enzyme from O-2 damage and high-potential deactivation. Electron transfer between the polymer-bound viologen moieties controls the potential applied to the active site of the hydrogenase and thus insulates the enzyme from excessive oxidative stress. Under catalytic turnover, electrons provided from the hydrogen oxidation reaction induce viologen-catalysed O-2 reduction at the polymer surface, thus providing self-activated protection from O-2. The advantages of this tandem protection are demonstrated using a single-compartment biofuel cell based on an O-2-sensitive hydrogenase and H-2/O-2 mixed feed under anode-limiting conditions.