Figure 4: Stereo diiron centre configurations in different complexes and redox states of T4moH.
From: Structural basis for biomolecular recognition in overlapping binding sites in a diiron enzyme system
Positions of key residues Thr201 (yellow), Asn202 (green), Gln228 (purple), Glu231 (white) shown as sticks. Unique active site water molecules are identified by their PDB ID numbers. (a) Resting T4moH (PDB 3DHG) with diferric centre and iron atoms Fe1 and Fe2 identified. (b) Resting T4moHD (PDB 3DHH) with diferric centre and polyethylene glycol (1PE) bound to Fe1 and projecting into the substrate cavity. (c) Resting T4moHC (PDB 4P1B) with acetate (ACT2) bound in a bridging position between Fe2 and Fe1. (d) Reduced T4moHD (PDB 3DHI) with acetate (ACT605) bound in a bridging position that projects into the substrate cavity.
