Nitrogenase bioelectrocatalysis: heterogeneous ammonia and hydrogen production by mofe protein
Milton, Ross D.
Dean, Dennis R.
Seefeldt, Lance C.
Minteer, Shelley D.
MetadataShow full item record
This item's downloads: 0 (view details)
Cited 116 times in Scopus (view citations)
Milton, Ross D. Abdellaoui, Sofiene; Khadka, Nimesh; Dean, Dennis R.; Leech, Dónal; Seefeldt, Lance C.; Minteer, Shelley D. (2016). Nitrogenase bioelectrocatalysis: heterogeneous ammonia and hydrogen production by mofe protein. Energy Environ. Sci. 9 (8), 2550-2554
Nitrogenase is the only enzyme known to catalyze the reduction of N-2 to 2NH(3). In vivo, the MoFe protein component of nitrogenase is exclusively reduced by the ATP-hydrolyzing Fe protein in a series of transient association/dissociation steps that are linked to the hydrolysis of two ATP for each electron transferred. We report MoFe protein immobilized at an electrode surface, where cobaltocene (as an electron mediator that can be observed in real time at a carbon electrode) is used to reduce the MoFe protein (independent of the Fe protein and of ATP hydrolysis) and support the bioelectrocatalytic reduction of protons to dihydrogen, azide to ammonia, and nitrite to ammonia. Bulk bioelectrosynthetic N-3 or NO2 reduction (50 mM) for 30 minutes yielded 70 +/- 9 nmol NH3 and 234 +/- 62 nmol NH3, with NO2- reduction operating at high faradaic efficiency.