| 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 |
|---|---|---|---|---|---|---|---|---|---|---|
| 1A25-CA-2 | CA | Ca²⁺ | D2E1R1S1 | ARG.ASP.GLU.SER. | ARG.ASP.GLU.SER. | ✔ | 5 | 5 | 2 | ✔ |
| 1A25-CA-4 | CA | Ca²⁺ | D2E1R1S1 | ARG.ASP.GLU.SER. | ARG.ASP.GLU.SER. | ✔ | 5 | 5 | 2 | ✘ |