Fig. 3.

Binding mode of CAPS based on the atomic fitting with the electron density map. (A) CAPS fit within the electron density. (B) CAPS binding mode as balls and sticks, and the surrounding amino acids as surface. (C) The docked and density-fit binding modes of CAPS are very similar and involve merely a rotation along its long axis, with little penetration of the pocket. (D) The ligand interaction model of the binding modes of CAPS. Atoms of the amino acid residues in hydrophobic contacts with the ligand are shown as spheres. Hydrogen bonds are shown as green lines. The interatomic distances between the hydrogen bond donor and acceptor are shown up to 4.0 Å.