Download MendeleyStructural and Mechanistic Insights into CO2Activation by Nitrogenase Iron Protein.
Rettberg, L.A., Stiebritz, M.T., Kang, W., Lee, C.C., Ribbe, M.W., Hu, Y.(2019) Chemistry 25: 13078-13082
- PubMed: 31402524
- DOI: https://doi.org/10.1002/chem.201903387
- Primary Citation of Related Structures:
6O0B - PubMed Abstract:
The Fe protein of nitrogenase catalyzes the ambient reduction of CO 2 when its cluster is present in the all-ferrous, [Fe 4 S 4 ] 0 oxidation state. Here, we report a combined structural and theoretical study that probes the unique reactivity of the all-ferrous Fe protein toward CO 2 . Structural comparisons of the Azotobacter vinelandii Fe protein in the [Fe 4 S 4 ] 0 and [Fe 4 S 4 ] + states point to a possible asymmetric functionality of a highly conserved Arg pair in CO 2 binding and reduction. Density functional theory (DFT) calculations provide further support for the asymmetric coordination of O by the "proximal" Arg and binding of C to a unique Fe atom of the all-ferrous cluster, followed by donation of protons by the proximate guanidinium group of Arg that eventually results in the scission of a C-O bond. These results provide important mechanistic and structural insights into CO 2 activation by a surface-exposed, scaffold-held [Fe 4 S 4 ] cluster.
Organizational Affiliation:
Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-3900, USA.
