title: Reversible interconversion of CO2 and formate by a molybdenum-containing formate dehydrogenase.
abstract: CO2 and formate are rapidly, selectively, and efficiently interconverted by tungsten-containing formate dehydrogenases that surpass current synthetic catalysts. However, their mechanism of catalysis is unknown, and no tractable system is available for study. Here, we describe the catalytic properties of the molybdenum-containing formate dehydrogenase H from the model organism Escherichia coli (EcFDH-H). We use protein film voltammetry to demonstrate that EcFDH-H is a highly active, reversible electrocatalyst. In each voltammogram a single point of zero net current denotes the CO2 reduction potential that varies with pH according to the Nernst equation. By quantifying formate production we show that electrocatalytic CO2 reduction is specific. Our results reveal the capabilities of a Mo-containing catalyst for reversible CO2 reduction and establish EcFDH-H as an attractive model system for mechanistic investigations and a template for the development of synthetic catalysts.
authors.affiliation: Medical Research Council Mitochondrial Biology Unit, Hills Road, Cambridge, CB2 0XY, United Kingdom.
authors.forename: Arnau
authors.initials: A
authors.lastname: Bassegoda
authors.forename: Christopher
authors.initials: C
authors.lastname: Madden
authors.forename: David W
authors.initials: DW
authors.lastname: Wakerley
authors.forename: Erwin
authors.initials: E
authors.lastname: Reisner
authors.forename: Judy
authors.initials: J
authors.lastname: Hirst
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D005560:Formate Dehydrogenases / Q000737:chemistry*; D005561:Formates / Q000737:chemistry*; D008982:Molybdenum / Q000737:chemistry*
chemical_list: D005561:Formates; C030544:formic acid; D002245:Carbon Dioxide; D008982:Molybdenum; D005560:Formate Dehydrogenases