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Publication Abstract from PubMed

The Fe protein of nitrogenase catalyzes the ambient reduction of CO2 when its cluster is present in the all-ferrous, [Fe4 S4 ](0) oxidation state. Here, we report a combined structural and theoretical study that probes the unique reactivity of the all-ferrous Fe protein toward CO2 . Structural comparisons of the Azotobacter vinelandii Fe protein in the [Fe4 S4 ](0) and [Fe4 S4 ](+) states point to a possible asymmetric functionality of a highly conserved Arg pair in CO2 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 CO2 activation by a surface-exposed, scaffold-held [Fe4 S4 ] cluster.

Structural and Mechanistic Insights into CO2 Activation by Nitrogenase Iron Protein.,Rettberg LA, Stiebritz MT, Kang W, Lee CC, Ribbe MW, Hu Y Chemistry. 2019 Oct 11;25(57):13078-13082. doi: 10.1002/chem.201903387. Epub 2019, Sep 4. PMID:31402524^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.