Recent Enzymatic Electrochemistry for Reductive Reactions

Enzymatic electrochemistry is the coupling of oxidoreductase enzymes to electrodes, where electrons are transferred between the electrode and an enzyme's cofactor(s). In addition to enzymatic electrochemistry enabling mechanistic study [such as the determination of cofactor reduction potential(s)], enzymatic electrocatalysis also enables substrate reduction or oxidation by exploiting the catalytic properties of enzymes. This Minireview illustrates some recent examples, in which electrodes are coupled with enzymes that catalyze the reduction of substrates such as dinitrogen (N-2), carbon dioxide (CO2) and protons (H+), performed by metalloenzymes such as nitrogenases, formate dehydrogenases and hydrogenases. We review some strategies to achieve electron transfer (such as mediated and direct electron transfer), as well as some key results of recent studies.