| Id | Element | Ion | Binding family | Amino acids or nucleotide residues names | All bound residues | Is homomer | Number of bound amino acids or nucleotide residues | Number of all bound residues | Number of coordinating chains | Representative |
|---|---|---|---|---|---|---|---|---|---|---|
| 3ONR-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 3 | ✔ |
| 3ONR-CA-2 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 3 | ✘ |
| 3ONR-CA-3 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 4 | 3 | ✘ |
| 3ONR-CA-4 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 3 | ✘ |
| 4IC5-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 3 | ✔ |
| 4IT5-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 6 | 2 | ✔ |
| 4IT5-CA-3 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 2 | ✔ |
| 4OUL-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 6 | 3 | ✘ |
| 4M18-CA-2 | CA | Ca²⁺ | E3 | GLU. | GLU. | ✔ | 3 | 3 | 3 | ✘ |
| 3IKN-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 6 | 3 | ✘ |
| 3IKP-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 6 | 3 | ✘ |
| 3IKQ-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 6 | 3 | ✘ |
| 3IKR-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 6 | 3 | ✘ |
| 3BS6-CA-3 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 2 | ✔ |
| 3BS6-CA-4 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 2 | ✘ |
| 3MLI-CA-2 | CA | Ca²⁺ | E3 | GLU. | GLU. | ✔ | 3 | 3 | 2 | ✘ |
| 1YAX-CA-2 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 2 | ✔ |
| 1YAX-CA-3 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 2 | ✔ |
| 1YAX-CA-4 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 2 | ✘ |
| 6D72-CA-1 | CA | Ca²⁺ | E3 | GLU. | GLU.HOH. | ✔ | 3 | 5 | 2 | ✘ |