The substrate-induced conformational switch is the same in protozoan and human CYP51. Superimposed structures of obtusifoliol-bound (magenta) and ligand-free (blue) T. cruzi CYP51 (PDB code 6FMO), RMSD of Cα of 1.83 Å, maximal XYZ displacement of 7.55 Å (A), and lanosterol-bound (violet, PDB code 6UEZ) and VFV-bound (green, PDB code 4UHI) human CYP51, RMSD of Cα of 1.98 Å, maximal XYZ displacement of 9.44 Å (B). Middle, the overall distal P450 view. The arrows mark the areas of the molecules enlarged above (rearrangements for electron delivery) and below (rearrangements for proton delivery). The conserved salt bridges are shown as red dashes.