Investigations by Protein Film Electrochemistry of Alternative Reactions of Nickel-Containing Carbon Monoxide Dehydrogenase

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• 作者：Vincent C.-C. Wang ; Shams T. A. Islam ; Mehmet Can ; Stephen W. Ragsdale ; Fraser A. Armstrong
• 刊名：Journal of Physical Chemistry B
• 出版年：2015
• 出版时间：October 29, 2015
• 年：2015
• 卷：119
• 期：43
• 页码：13690-13697
• 全文大小：451K
• ISSN：1520-5207

文摘

Protein film electrochemistry has been used to investigate reactions of highly active nickel-containing carbon monoxide dehydrogenases (CODHs). When attached to a pyrolytic graphite electrode, these enzymes behave as reversible electrocatalysts, displaying CO₂ reduction or CO oxidation at minimal overpotential. The O₂ sensitivity of CODH is suppressed by adding cyanide, a reversible inhibitor of CO oxidation, or by raising the electrode potential. Reduction of N₂O, isoelectronic with CO₂, is catalyzed by CODH, but the reaction is sluggish, despite a large overpotential, and results in inactivation. Production of H₂ and formate under highly reducing conditions is consistent with calculations predicting that a nickel-hydrido species might be formed, but the very low rates suggest that such a species is not on the main catalytic pathway.