FIGURE 7.

The PDE5 structure bound to evodiamine and avanafil. (a) PDE5 bound to evodiamine in the allosteric site. The hydrogen bonds formed with the residues His617, Tyr612, Asn614, and Asp563 are shown using blue dashed lines. The residues are shown in ball and stick representations, and the evodiamine molecule is shown in a licorice representation. (b) PDE5 bound to avanafil (licorice representation) in the catalytic site. The π–π interactions with the residues Phe786 and Phe820 are shown via red arrows. The halogen bond between avanafil:Cl and Ala:779:O atoms, is shown via an orange dashed line. The hydrogen bond with Gln817 is shown using a blue dashed line. The atoms are uniquely colored: black, carbon; red, oxygen; blue, nitrogen; white, hydrogen; and cyan, chlorine.