FOR
PCM
| Residue type | PCM type | Category | Position | UniProt PTM accession | Entries in PDB |
| CYS | None | Crosslinker | Amino-acid side chain (Any position) | 24 | |
| HIS | None | Crosslinker | Amino-acid side chain (Any position) | 1 | |
| LYS | None | Crosslinker | Amino-acid side chain (Any position) | 14 | |
| PRO | None | Crosslinker | Amino-acid backbone (N-terminal) | 2 | |
| TYR | None | Crosslinker | Amino-acid side chain (Any position) | 1 |
