Details

Autor(en) / Beteiligte

• Liu, Chong
• Sakimoto, Kelsey K.
• Colón, Brendan C.
• Silver, Pamela A.
• Nocera, Daniel G.

Titel

Ambient nitrogen reduction cycle using a hybrid inorganic–biological system

Ist Teil von

• Proceedings of the National Academy of Sciences - PNAS, 2017-06, Vol.114 (25), p.6450-6455

Ort / Verlag

United States: National Academy of Sciences

Erscheinungsjahr

2017

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• We demonstrate the synthesis of NH₃ from N₂ and H₂O at ambient conditions in a single reactor by coupling hydrogen generation from catalytic water splitting to a H₂-oxidizing bacterium Xanthobacter autotrophicus, which performs N₂ and CO₂ reduction to solid biomass. Living cells of X. autotrophicus may be directly applied as a biofertilizer to improve growth of radishes, a model crop plant, by up to ∼1,440% in terms of storage root mass. The NH₃ generated from nitrogenase (N₂ase) in X. autotrophicus can be diverted from biomass formation to an extracellular ammonia production with the addition of a glutamate synthetase inhibitor. The N₂ reduction reaction proceeds at a low driving force with a turnover number of 9 × 10⁹ cell−1 and turnover frequency of 1.9 × 10⁴ s−1·cell−1 without the use of sacrificial chemical reagents or carbon feedstocks other than CO₂. This approach can be powered by renewable electricity, enabling the sustainable and selective production of ammonia and biofertilizers in a distributed manner.