Figure 6.

Examples of hydration sites derived from the reference crystal structure that bridged hydrogen bonds between the protein and ligand in other experimental structures. In each case, the hydration site did not bridge hydrogen bonds between the protein and ligand in the reference crystal structure. Two crystal structures for three different proteins are shown: (A, B) Tyrosine-protein kinase JAK2 (PDB codes: 4d0w and 4zim); (C, D) Thrombin (PDB codes: 2hj6 and 3p17); (E, F) Trypsin I (PDB codes: 1c1t and 3a7y). Hydration sites and crystal waters are shown as transparent green and red spheres, respectively. The proteins are shown as gray cartoons with selected residues in sticks. The cocrystallized ligands are depicted in sticks with either blue (reference crystal structure) or yellow (other crystal structure) carbon atoms. Hydrogen bonds are depicted as black dashed lines.