Enhancing stability of biocatalyst for fuel cells and bioelectrocatalysis

Progress in biotechnology over the last two decades has greatly increased the use of biocatalyst in the industrial production of fine chemicals. Advantages of biocatalysts over chemical catalyst are their (stereo)selectivity, higher turnover frequencies (TOF), ‘green’ as well as sustainable production and optimal activity under mild pH and temperature conditions. Fundamental reactions in energy conversion and storage are also catalysed by enzymes, but many of these reside in biological lipid membranes, including enzymes active in hydrogen oxidation and evolution, carbon capture (e.g., CO2 to formate) and oxygen reduction. Membrane enzymes, however, are usually not considered for biocatalysis because of high cost of purification and low stability in detergent environments. In stark contrast to this generally held belief, our recent result show that membrane enzymes exhibit specific properties that make them suitable for a specific biotechnological application, electrocatalysis.

In this PhD project you will aim to exploit membrane enzymes for applications in bioelectrocatalysis, in particular for bioenergy related applications such as biofuel cells. Your aim is supported by our recent results, which show that ‘cheap-to-produce’ crude membrane extracts are suitable catalyst systems and that amphiphilic polymers are able to induce an unprecedented improvement in biocatalyst stability. As a proof-of-principle, your will use two membrane enzymes, membrane-bound hydrogenase (hydrogen oxidation) and cytochrome bo3 (oxygen reduction), to create a cheap and robust enzyme-based hydrogen-air fuel cell. This technology will advance the area of industrial biomanufacturing and open up the use of membrane enzymes in biocatalysis and in particularly, bioelectrocatalysis.