TransCO2 · Electricity-Driven Enzymatic Cascades to Transform CO2 to C2+ Chemicals

The increasing level of carbon dioxide (CO2) in the atmosphere presents a critical factor for climate change and action must be taken urgently to minimise its impact. Using CO2 as a carbon source in the chemical industry for its conversion into valuable chemicals is an advantageous strategy to reduce CO2 emissions and provide a sustainable and cheap source of raw materials to help combat raw material scarcity. Interfacing CO2 reducing enzyme/enzymatic cascades with electrocatalysis present a particular approach to directly power product generation from CO2 with renewable electricity. This was achieved for a few enzymatic cascades; however, these proof-of-concept demonstrations are far from practical use due to lack of efficient method to guide the rational design of these complex multi-enzymes cascades on electrodes, resulting in high costs and low yields. Within this project (TransCO2), my overarching aim is to apply quantitative analysis and rational assembly of enzymatic cascades to enable a breakthrough in bioelectrocatalytic-technology to transform carbon dioxide (CO2) directly into high value mevalonate (C5) at high isolated yields, using electricity as energy source. Specifically, CO2 is firstly converted to formate by the enzyme Formate dehydrogenase (FDH), which is then further converted to mevalonate via 8 steps enzymatic conversions. The whole system will function in an electrochemical cell to make use of electricity as power input. I will build a kinetic model for this enzymatic cascade and implement it to guide the design and optimisation towards highest efficiency with minimal utilization of expensive cofactors.The overall technology in TransCO2 will be a generally applicable breakthrough for efficient production of high-value chemicals from CO2, enabling the large-scale use of CO2 utilisation.