Communication—Highly Efficient Electroenzymatic NADH Regeneration by an Electron-Relay Flavoenzyme

Abstract

Efficient cofactor regeneration is essential for the utilization of many oxidoreductases. Herein, the β-subunit of formate dehydrogenase 1 from Methylobacterium extorquens AM1 (MeFDH1-β) was employed as a novel electroactive biocatalyst for electroenzymatic NADH regeneration for the first time. MeFDH1-β showed much better properties in both catalytic activity (a turnover frequency of 3,600 hr−1) and current efficiency (ca. 98%) than a conventional rhodium (III)-based chemical catalyst (M = [Cp*Rh(bpy)H2O]2+, Cp* = C5Me5, bpy = 2,2′-bipyridine) and a traditional biocatalyst (diaphorase).