CHAPTER 5: Electrochemistry of Molybdenum and Tungsten Enzymes

As nearly all Mo- and W-dependent enzymes catalyze oxidation and reduction reactions, electrochemistry is an ideal physical method to be applied in the study of the reactivity of these systems. Electrochemical communication between the enzyme and an electrode is of paramount importance and many experimental approaches can be taken to achieve this goal. In this chapter a comprehensive review of the literature of Mo and W enzyme electrochemistry is presented. Direct electrochemistry, where the enzyme is oxidized and reduced at the electrode without any mediators, is experimentally difficult but, when successful, has brought new insight to enzyme function. The use of electron transfer relays (mediators) to achieve better communication with the enzyme is more common and these cases have also been included herein. The application of Mo and W enzyme electrochemistry in biosensors and also in larger scale biotransformations is covered.