With a growing world population, depleting fossil resources and ongoing climate change, innovative new approaches are needed to reintegrate the greenhouse gas carbon dioxide into a circular economy and provide sustainable sources of energy and materials for future generations. An important step towards a carbon-neutral bioeconomy is the valorization of carbon dioxide as a feedstock. Most commodity chemicals are still derived exclusively from fossil resources such as oil, natural gas and coal. Biomanufacturing through fermentation enables the sustainable, targeted production of desired chemicals using "above-ground" carbon sources.
Recently, several routes for the direct utilization of carbon dioxide have been proposed, including autotrophic microorganisms with the natural ability to grow on C1 compounds, synthetic carbon dioxide fixation pathways, and the design of synthetic autotrophs. While the various engineered synthetic pathways for carbon dioxide utilization seem promising in terms of efficiency and modularity, these approaches mostly suffer from reduced energy supply, compartmentalization, host selection, and net carbon dioxide assimilation.
ConCO2rde's goal was to harness the power of autotrophic microorganisms to use renewable energy (e.g. green hydrogen) for the accumulation of biomass directly from carbon dioxide to synthesize valuable chemicals with much lower environmental impact. To achieve this goal, ConCO2rde has leveraged complementary expertise in synthetic biology, metabolic engineering, biocatalysis and process engineering, with strong participation from industrial partners. ConCO2rde trained 11 Early Stage Researchers (ESRs) in cutting-edge research projects on (i) the combination of synthetic biology with metabolic and process engineering to create an efficient pathway from carbon dioxide fixation to chemical production, (ii) the application of hydrogen-driven biotransformations using redox enzymes for the synthesis of high-value chemicals, and (iii) the development of novel reactor concepts for gas fermentations using hydrogen, carbon dioxide and oxygen towards commercially relevant processes. The close interaction between academia and industry was crucial in qualifying these young scientists to take up decision-making positions within the European biotech sector and make a difference for sustainability and the circular carbon bioeconomy. Overall, ConCO2rde's interdisciplinary consortium of 17 leading academic and private organizations provided the ideal environment to foster complementary expertise in synthetic biology, metabolic engineering, biocatalysis and process engineering, while providing 11 young researchers with in-depth training in an interdisciplinary working environment, strengthened by transferable skills training with strong industrial participation.
