Enhancing Biocatalysis with Electrons

Enzymes are increasingly being used as biocatalysts for a number of industrial processes.[1] However, despite their great potential for biocatalysis, the current usage of enzymes in industry remains critically low. This low uptake is in part due to the reliance of many enzymes on prohibitively expensive cofactors such as NADPH, which is a significant hurdle for industry. This project seeks to explore the fundamental aspects of redox-active enzymes through a comprehensive study of enzyme structure, single molecule redox behaviour, and interaction with the surrounding environment. Through rational design of the reaction media and chemical modification of enzymes, the project will investigate applications of redox enzymes in electron-fed biocatalytic processes and energy production (in bioelectrochemical cells).
The project will be centred around an exploration of the bioelectrochemistry, electron transfer, and associated biocatalysis of redox-active metalloproteins (such as heme containing cytochrome P450) and FAD-dependent-enzymes (such as glutathione reductase). The core purpose is to examine the possibility of replacing cofactors such as NADPH with a molecular mediator and an electrode to drive enzyme-catalysed processes with electrons alone, resulting in more green, sustainable, and controllable biocatalysis.[2] This will be benchmarked in aqueous media (known)[3] and the much broader range of environments enabled by non-aqueous environments (unknown). The goals will be (a) to use these in energy harvesting devices, e.g. thermoelectrochemical cells to turn waste body heat into electricity,[3] and (b) applying electricity to speed up the production of value added compounds (bioelectrocatalysis).