Best docked poses of ligands. (a, b) for agonist epinephrine and (c, d) for antagonist ICI in open (magenta) and closed (light blue) forms of the receptor, showing both top and side views. Ligands are shown in sticks representation in the same color with its docked structure. Key residues interacting with the ligand are labeled and also shown as ball-and-stick. For comparison, the bound state of ICI in the crystal structure (PDB:3NY8) is shown in black. All molecular graphics were prepared using PyMOL  and VMD  in this article.