| 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 6K7Y-CA-2 | CA | Ca²⁺ | E4 | GLU. | GLU. | ✔ | 4 | 4 | 4 | ✘ |
| 1NSD-CA-1 | CA | Ca²⁺ | E4 | GLU. | GLU.HOH. | ✔ | 4 | 5 | 4 | ✘ |
| 1NSC-CA-1 | CA | Ca²⁺ | E4 | GLU. | GLU.HOH. | ✔ | 4 | 5 | 4 | ✔ |
| 1NSB-CA-1 | CA | Ca²⁺ | E4 | GLU. | GLU.HOH. | ✔ | 4 | 5 | 4 | ✘ |