| 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 4FT8-CO-2 | CO | Co²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 3 | 2 | ✘ |
| 1CIA-CO-1 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 1CIA-CO-2 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 1CIA-CO-3 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 1CLA-CO-1 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 1CLA-CO-2 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 1CLA-CO-3 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 1FA6-CO-1 | CO | Co²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 4 | 2 | ✘ |
| 1FA6-CO-2 | CO | Co²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 4 | 2 | ✘ |
| 1FOF-CO-1 | CO | Co²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 4 | 2 | ✔ |
| 1FOF-CO-2 | CO | Co²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 4 | 2 | ✘ |
| 1T31-CO-1 | CO | Co²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 5 | 2 | ✔ |
| 1QCA-CO-1 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 1QCA-CO-2 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 1QCA-CO-3 | CO | Co²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✘ |
| 4MTQ-NI-1 | NI | Ni²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 3 | 2 | ✘ |
| 4MTQ-NI-2 | NI | Ni²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 3 | 2 | ✘ |
| 3MMU-CD-1 | CD | Cd²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 4 | 2 | ✔ |
| 6F5N-NI-1 | NI | Ni²⁺ | E2 | GLU. | GLU.HOH. | ✔ | 2 | 4 | 2 | ✔ |
| 5FSH-NI-2 | NI | Ni²⁺ | E2 | GLU. | GLU. | ✔ | 2 | 2 | 2 | ✔ |