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AnfO controls fidelity of nitrogenase FeFe protein maturation by preventing misincorporation of FeV-cofactor.

ABSTRACT: Azotobacter vinelandii produces three genetically distinct, but structurally and mechanistically similar nitrogenase isozymes designated as Mo-dependent, V-dependent, or Fe-only based on the heterometal contained within their associated active site cofactors. These catalytic cofactors, which provide the site for N₂ binding and reduction, are, respectively, designated as FeMo-cofactor, FeV-cofactor, and FeFe-cofactor. Fe-only nitrogenase is a poor catalyst for N₂ fixation, when compared to the Mo-dependent and V-dependent nitrogenases and is only produced when neither Mo nor V is available. Under conditions favoring the production of Fe-only nitrogenase a gene product designated AnfO preserves the fidelity of Fe-only nitrogenase by preventing the misincorporation of FeV-cofactor, which results in the accumulation of a hybrid enzyme that cannot reduce N₂ . These results are interpreted to indicate that AnfO controls the fidelity of Fe-only nitrogenase maturation during the physiological transition from conditions that favor V-dependent nitrogenase utilization to Fe-only nitrogenase utilization to support diazotrophic growth.

SUBMITTER: Perez-Gonzalez A

PROVIDER: S-EPMC9310841 | biostudies-literature |

REPOSITORIES: biostudies-literature

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