Formate Dehydrogenases Reduce CO2 Rather than HCO3- : An Electrochemical Demonstration

Abstract

Mo/W formate dehydrogenases catalyze the reversible reduction of CO₂ species to formate. It is thought that the substrate is CO₂ and not a hydrated species like HCO₃^- , but there is still no indisputable evidence for this, in spite of the extreme importance of the nature of the substrate for mechanistic studies. We devised a simple electrochemical method to definitively demonstrate that the substrate of formate dehydrogenases is indeed CO₂ .

Keywords: CO dehydrogenase; CO2 reduction; bioelectrochemistry; carbonic anhydrase; protein film voltammetry.