Insight into the Mechanistic Basis of the Hysteretic-Like Kinetic Behavior of Thioredoxin-Glutathione Reductase (TGR)

Figure 9

(a) Dimeric structure of S. mansoni TGR as derived from X-ray crystallography. Monomers of the enzyme are shown in either blue or red and the location of the glutaredoxin domains is indicated. The enzyme was placed such that the region in which both the NADPH and the FAD binding sites, enclosed in an oval, could be viewed. (b) Amplified view showing details of the potential binding site for GSSG as inhibitor as derived from docking studies. The reducing substrate NADPH, as well as the prosthetic group FAD and the redox active disulfide (in yellow), are shown in stick. The catalytically essential selenocysteine residue of the partner subunit is shown in green.

(a)

(b)