| Code | Name | Deposits | Targets | Ligand Type |
|---|---|---|---|---|
| BGC | 2 | 2 | crystallization | |
| BMA | beta-d-mannose | 1 | 1 | modified residue |
| BME | beta mercaptoethanol | 15 | 13 | crystallization |
| BME | beta mercaptoethanol | 3 | 3 | other |
| BO3 | 2 | 2 | crystallization | |
| bpa | unknown | 1 | 1 | crystallization |
| BR | bromide ion | 3 | 3 | crystallization |
| BTB | 2-[bis-(2-hydroxy-ethyl)-amino]-2-hydroxymethyl-propane-1,3-diol | 13 | 10 | crystallization |
| BTB | 2-[bis-(2-hydroxy-ethyl)-amino]-2-hydroxymethyl-propane-1,3-diol | 1 | 1 | other |
| BU1 | 3 | 2 | crystallization | |
| BU1 | 1 | 1 | other | |
| C91 | unknown | 3 | 3 | biological |
| CA | calcium ion | 5 | 4 | biological |
| CA | calcium ion | 42 | 38 | crystallization |
| CA | calcium ion | 18 | 17 | other |
| CAC | 2 | 2 | crystallization | |
| CAC | 3 | 3 | other | |
| CAF | s-dimethylarsinoyl-cysteine | 1 | 1 | modified residue |
| CD | Cadmium | 1 | 1 | biological |
| CD | Cadmium | 4 | 4 | crystallization |