Designed mono- and di-covalent inhibitors trap modeled functional motions for <i>Trypanosoma cruzi</i> proline racemase in crystallography - Fig 6

Close views of the binding sites showing conformational changes for (A) the crystal co-complexes with PYC (1W62-A, pink), OxoPA (chain B, white), and NG-P27 (chain B, cyan), and for (B) for transitional model intermediates, conf1A (pink), conf4A (white) and conf10A (cyan). Main chains are presented by ribbons, sidechains, thin sticks for amino acids of the binding site (see list in Materials and Methods). Catalytic cysteines, the ligand and residues making hydrogen bonds (dashed lines) with the ligand carboxylic moiety (C130 G131, H132, C300, G301, T302) are displayed in bolder sticks, and non carbon atoms as blue, red, and yellow spheres for nitrogen, oxygen and sulfur, respectively. The crystallographic ligands are also represented with lines in the transitional models for reference. Amino acids C130, N218, F290 are labeled, and regions 127–130 and 289–291 of the backbone are labeled with * and Ø signs.