Table 1. PDB protein–ligand search filtration results at each stage.
Stage | Filter | PDBs | His | Arg | Lys | Total |
a | 2.0 ≥ Å resolution, containing ligand | 30 053 | — | — | — | 30 053 |
b | Geometric thresholds | 3248 | 4959 | 3141 | 930 | 9030 |
c | Residue pKa >7.4 | 1827 | 68 | 2954 | 848 | 3870 |
d | Non-redundant chain and polycyclic ligand | 1827 | 49 | 1381 | 582 | 2012 |