Arren Bar-Even

Abstract The direct reduction of CO2 into one-carbon molecules is key to highly efficient biological CO2-fixation. However, this strategy is currently restricted to anaerobic organisms and low redox potentials. In this study, we introduce the CORE cycle, a synthetic metabolic pathway that converts CO2 to formate at aerobic conditions and ambient CO2 levels, using only NADPH as a reductant.

Abstract Auxotrophic metabolic sensors (AMS) are microbial strains modified so that biomass formation correlates with the availability of specific metabolites. These sensors are essential for bioengineering (e.g., in growth-coupled designs) but creating them is often a time-consuming and low-throughput process that can be streamlined by in silico analysis. Here, we present a systematic workflow for designing, implementing, and testing versatile AMS based on Escherichia coli.

Abstract One-carbon feedstocks such as formate could be promising renewable substrates for sustainable microbial production of food, fuels and chemicals. Here we replace the native energy-inefficient Calvin–Benson–Bassham cycle in Cupriavidus necator with the more energy-efficient reductive glycine pathway for growth on formate and CO2. In chemostats, our engineered strain reached a 17% higher biomass yield than the wild type and a yield higher than any natural formatotroph using the Calvin cycle.