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An Fe₆ C Core in All Nitrogenase Cofactors.

ABSTRACT: The biological process of dinitrogen reduction to ammonium occurs at the cofactors of nitrogenases, the only enzymes that catalyze this challenging chemical reaction. Three types of nitrogenases have been described, named according to the heterometal in their cofactor: molybdenum, vanadium or iron nitrogenases. Spectroscopic and structural characterization allowed the unambiguous identification of the cofactors of molybdenum and vanadium nitrogenases and revealed a central μ₆ -carbide in both of them. Although genetic studies suggested that the cofactor of the iron nitrogenase contains a similar Fe₆ C core, this has not been experimentally demonstrated. Here we report Valence-to-Core X-ray Emission Spectroscopy providing experimental evidence that this cofactor contains a carbide, thereby making the Fe₆ C core a feature of all nitrogenase cofactors.

SUBMITTER: Decamps L

PROVIDER: S-EPMC9826452 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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An Fe6 C Core in All Nitrogenase Cofactors.

Decamps Laure L Rice Derek B DB DeBeer Serena S

Angewandte Chemie (International ed. in English) 20220907 41

The biological process of dinitrogen reduction to ammonium occurs at the cofactors of nitrogenases, the only enzymes that catalyze this challenging chemical reaction. Three types of nitrogenases have been described, named according to the heterometal in their cofactor: molybdenum, vanadium or iron nitrogenases. Spectroscopic and structural characterization allowed the unambiguous identification of the cofactors of molybdenum and vanadium nitrogenases and revealed a central μ6 -carbide ...[more]

PMID: 35975943

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