Engineered synthetic one-carbon fixation exceeds yield of the Calvin Cycle

Dronsella, B. B.; Orsi, E.; Benito-Vaquerizo, S.; Glatter, T.; Bar-Even, A.; Erb, T. J.; Claassens, N. J.

doi:10.1101/2022.10.19.512895

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bioRxiv · 10.1101/2022.10.19.512895

Engineered synthetic one-carbon fixation exceeds yield of the Calvin Cycle

Dronsella, B. B.·Orsi, E.·Benito-Vaquerizo, S.·Glatter, T.·Bar-Even, A.·Erb, T. J.·Claassens, N. J.

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Abstract

One-carbon (C1) feedstocks derived from CO2 and renewable electricity, such as formate, are promising substrates for sustainable production of chemicals, food and fuels. Energetically more efficient, engineered C1-fixation pathways were proposed to increase biomass yields above their natural counterparts, but have so far not been shown to achieve this. Here, we replace the native energy-inefficient Calvin-Benson-Bassham (CBB) cycle in Cupriavidus necator by genomic integration of the synthetic reductive glycine pathway for growth on formate. Our final engineered strain reaches a higher biomass yield than the CBB-cycle-utilizing wild type, showing for the first time that efficiencies found in natural metabolism can be exceeded via a synthetic pathway. This yield increase demonstrates the potential of synthetic metabolism and is an important step towards realizing truly sustainable, economically feasible bio-based production.

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Dronsella, B. B., Orsi, E., Benito-Vaquerizo, S., Glatter, T., Bar-Even, A., Erb, T. J., Claassens, N. J.. 2022-10-20. Engineered synthetic one-carbon fixation exceeds yield of the Calvin Cycle. https://doi.org/10.1101/2022.10.19.512895

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