Upcycling CO 2 into energy-rich long-chain compounds via electrochemical and metabolic engineering

Upcycling of carbon dioxide (CO 2 ) into value-added products represents a substantially untapped opportunity to tackle environmental issues and achieve a circular economy. Compared with easily available C 1 /C 2 products, nevertheless, efficient and sustainable synthesis of energy-rich long-chain compounds from CO 2 still remains a grand challenge. Here we describe a hybrid electro-biosystem, coupling spatially separate CO 2 electrolysis with yeast fermentation, that efficiently converts CO 2 to glucose with a high yield. We employ a nanostructured copper catalyst that can stably catalyse pure acetic acid production with a solid-electrolyte reactor. We then genetically engineer Saccharomyces cerevisiae to produce glucose in vitro from electro-generated acetic acid by deleting all defined hexokinase genes and overexpression of heterologous glucose-1-phosphatase. In addition, we showcase that the proposed platform can be easily extended to produce other products like fatty acids using CO 2 as the carbon source. These results illuminate the tantalizing possibility of a renewable-electricity-driven manufacturing industry.