Figure 6: Structural basis for supramolecular ligand activity.

(a) Overall structure of PXR-LBD in complex with EE2 (blue) and TNC (orange); the structure shows the LBP bordered by helix H12 (light brown) on one side and the β-sheet (green) on the other side; for clarity helix H3 is partially cut. (b) Electron density of ligands (2Fo-Fc map contoured at 1σ). (c) Interaction network of ligands with residues of the LBP (grey); red dashed lines highlight the interactions between EE2 and TNC resulting in a mutual stabilization of the compounds in the LBP. Colour code: red, oxygen; blue, nitrogen; yellow, sulphur; green, chlorine; black dashed lines, hydrogen bonds.