Anchor points for inhibitor 2 in the Pin1 active site. Left: Phosphate binding pocket. Salt bridge distances from Lys63, Arg68, and Arg69 to the phosphate oxygens of 2 are shown. Right: The proline-ring binding pocket is composed of hydrophobic residues: His157, His59, Leu122, Phe134, and Met130. Met130 also has a hydrophobic interaction with the tryptamine indole ring. (Created with MacPyMOL 2006.(41))