Structure of precursor-bound NifEN: a nitrogenase FeMo cofactor maturase/insertase.

ABSTRACT: NifEN plays an essential role in the biosynthesis of the nitrogenase iron-molybdenum (FeMo) cofactor (M cluster). It is an ?(2)?(2) tetramer that is homologous to the catalytic molybdenum-iron (MoFe) protein (NifDK) component of nitrogenase. NifEN serves as a scaffold for the conversion of an iron-only precursor to a matured form of the M cluster before delivering the latter to its target location within NifDK. Here, we present the structure of the precursor-bound NifEN of Azotobacter vinelandii at 2.6 angstrom resolution. From a structural comparison of NifEN with des-M-cluster NifDK and holo NifDK, we propose similar pathways of cluster insertion for the homologous NifEN and NifDK proteins.

SUBMITTER: Kaiser JT 

PROVIDER: S-EPMC3138709 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature