Oxidation-State-Dependent Binding Properties of the Active Site in a Mo-Containing Formate Dehydrogenase.

ABSTRACT: Molybdenum-containing formate dehydrogenase H from Escherichia coli (EcFDH-H) is a powerful model system for studies of the reversible reduction of CO₂ to formate. However, the mechanism of FDH catalysis is currently under debate, and whether the primary Mo coordination sphere remains saturated or one of the ligands dissociates to allow direct substrate binding during turnover is disputed. Herein, we describe how oxidation-state-dependent changes at the active site alter its inhibitor binding properties. Using protein film electrochemistry, we show that formate oxidation by EcFDH-H is inhibited strongly and competitively by N₃^-, OCN^-, SCN^-, NO₂^-, and NO₃^-, whereas CO₂ reduction is

SUBMITTER: Robinson WE 

PROVIDER: S-EPMC5532686 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature