The example is originally from PLINDER tutorial dataset `1s2g__1__1.A_2.C__1.D`.

Raw file from PLINDER:
* `ligand_files/1.D.sdf`
* `receptor.pdb`

A manually modified version of `receptor.pdb` by replacing resname `HIS` to `HSD` was tested for certain protonated state.
* `receptor_hsd.pdb`

Suggested by [our PDB tutorial](https://prolif.readthedocs.io/en/latest/notebooks/pdb.html#pdb):
The protonated protein was prepared with [PypKa](https://pypka.org/) and its default settings. However, some atoms are too close to recognize bonds correctly. Need to fix manually.
* `receptor_ph7_amber.pdb`

The protonated ligand was prepared by PyMOL3.
* `ligand_files/1.D_protonated.sdf`