Nitrogenase - Fe Protein

The iron protein of nitrogenase is responsible for electron transfer and for controlling the redox potential.

When a Mg-ATP unit docks on the protein, its reduction potential is lowered by ca. 100 mV. This step is a prerequisite for electron transfer to the Mo-Fe protein, where nitrogen is reduced.

  monomeric unit

  FeS clusters

  Mg-ADP

  Attachment of the iron-sulfur cluster to the protein (a typical Fe₄S₄ cluster
      with 4 cysteine residues and 4 sulfido ligands)

  Binding pocket for ADP