Normal-coordinate structural decomposition of X-ray crystal structures of prostaglandin H synthase-1

Large structural difference in the out-of-plane conformation of the heme occur for different inhibitors bound at the cyclooxygenase active site.   Similarly for prostaglandin H synthase-2...

Caution:  The prostaglandin H synthase crystal structures are at very low resolution (~3.5 Angstroms), so it is possible that these differences are merely a consequence of the uncertainties in the atomic positions.