Understanding the P-Cluster of Vanadium Nitrogenase: an EPR and XAS Study of the Holo vs. Apo Forms of the Enzyme.

ABSTRACT: The catalytic moiety of nitrogenases contains two complex metalloclusters: The M-cluster (also called cofactor), where the catalytic reduction of substrates takes place, and the [Fe₈S₇] P-cluster responsible for electron transfer. Due to discrepancies between crystallography and EPR spectroscopy, the exact structure of the P-cluster in the VFe protein remains a topic of debate. Herein, we use an apo-form of VFe (which retains the P-cluster but lacks the FeVco) to study the VFe P-cluster. SDS-PAGE and NativePAGE showed a heterogeneous composition of the VFe and the apo-VFe samples with the presence of α₁β₂δ₂ and α₁β₂ complexes. The parallel mode EPR measurements of IDS oxidized MoFe, apo-MoFe, and VFe samples revea

SUBMITTER: Wahl IM 

PROVIDER: S-EPMC11823357 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature