7JRF

CO-CO-BOUND NITROGENASE MOFE-PROTEIN FROM A. VINELANDII

Summary for 7JRF

• Entry DOI: 10.2210/pdb7jrf/pdb
• Descriptor: Nitrogenase molybdenum-iron protein alpha chain, MAGNESIUM ION, Nitrogenase molybdenum-iron protein beta chain, ... (11 entities in total)
• Functional Keywords: nitrogenase, femo-cofactor, inhibition, oxidoreductase
• Biological source: Azotobacter vinelandii; More
• Total number of polymer chains: 4
• Total formula weight: 233924.99

Authors

Spatzal, T.,Perez, K.A.,Buscagan, T.M.,Maggiolo, A.O.,Rees, D.C. (deposition date: 2020-08-12, release date: 2021-03-24, Last modification date: 2023-10-18)

Primary citation

Buscagan, T.M.,Perez, K.A.,Maggiolo, A.O.,Rees, D.C.,Spatzal, T.
Structural Characterization of Two CO Molecules Bound to the Nitrogenase Active Site.
Angew.Chem.Int.Ed.Engl., 60:5704-5707, 2021

PubMed Abstract: As an approach towards unraveling the nitrogenase mechanism, we have studied the binding of CO to the active-site FeMo-cofactor. CO is not only an inhibitor of nitrogenase, but it is also a substrate, undergoing reduction to hydrocarbons (Fischer-Tropsch-type chemistry). The C-C bond forming capabilities of nitrogenase suggest that multiple CO or CO-derived ligands bind to the active site. Herein, we report a crystal structure with two CO ligands coordinated to the FeMo-cofactor of the molybdenum nitrogenase at 1.33 Å resolution. In addition to the previously observed bridging CO ligand between Fe2 and Fe6 of the FeMo-cofactor, a new ligand binding mode is revealed through a second CO ligand coordinated terminally to Fe6. While the relevance of this state to nitrogenase-catalyzed reactions remains to be established, it highlights the privileged roles for Fe2 and Fe6 in ligand binding, with multiple coordination modes available depending on the ligand and reaction conditions.

PubMed: 33320413
DOI: 10.1002/anie.202015751

Experimental method

X-RAY DIFFRACTION (1.33 Å)