Hybrid molecular/enzymatic catalytic cascade for complete electro-oxidation of glycerol using a promiscuous NAD-dependent formate dehydrogenase from Candida boidinii

Abstract

Glycerol is a common fuel considered for bioenergy applications. Computational docking studies were performed on formate dehydrogenase from Candida boidinii (cbFDH) that showed that mesoxalate can bind to the buried active site of the holo form predicting that mesoxalate, a byproduct of glycerol oxidation, may act as its substrate. Spectroscopic assays and characterization by HPLC and GC/TCD have shown for the first time that cbFDH can act as a decarboxylase with mesoxalate. From this assessment, cbFDH was combined with NH₂-TEMPO to form a novel hybrid anode to oxidize glycerol to carbon dioxide at near-neutral pH.