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The iron nitrogenase reduces carbon dioxide to formate and methane under physiological conditions: A route to feedstock chemicals.

ABSTRACT: Nitrogenases are the only known enzymes that reduce molecular nitrogen (N₂) to ammonia. Recent findings have demonstrated that nitrogenases also reduce the greenhouse gas carbon dioxide (CO₂), suggesting CO₂ to be a competitor of N₂. However, the impact of omnipresent CO₂ on N₂ fixation has not been investigated to date. Here, we study the competing reduction of CO₂ and N₂ by the two nitrogenases of Rhodobacter capsulatus, the molybdenum and the iron nitrogenase. The iron nitrogenase is almost threefold more efficient in CO₂ reduction and profoundly less selective for N₂ than the molybdenum isoform under mixtures of N₂ and CO₂. Correspondingly, the growth rate of diazotrophically grown R. capsulatus strains relying on the iron nitrogenase notably decreased after adding CO₂. The in vivo CO₂ activity of the iron nitrogenase facilitates the light-driven extracellular accumulation of formate and methane, one-carbon substrates for other microbes, and feedstock chemicals for a circular economy.

SUBMITTER: Oehlmann NN

PROVIDER: S-EPMC11323892 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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The iron nitrogenase reduces carbon dioxide to formate and methane under physiological conditions: A route to feedstock chemicals.

Oehlmann Niels N NN Schmidt Frederik V FV Herzog Marcello M Goldman Annelise L AL Rebelein Johannes G JG

Science advances 20240814 33

Nitrogenases are the only known enzymes that reduce molecular nitrogen (N2) to ammonia. Recent findings have demonstrated that nitrogenases also reduce the greenhouse gas carbon dioxide (CO2), suggesting CO2 to be a competitor of N2. However, the impact of omnipresent CO2 on N2 fixation has not been investigated to date. Here, we study the competing reduction of CO2 and N2 by the two nitrogenases of Rhodob ...[more]

PMID: 39141735

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The iron nitrogenase reduces carbon dioxide to formate and methane under physiological conditions: A route to feedstock chemicals.

Publications

The iron nitrogenase reduces carbon dioxide to formate and methane under physiological conditions: A route to feedstock chemicals.

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