Complex with X77. The MX structure was solved both in non saturating conditions (again 1:1 and 1:2 LMS, PDBid: 8P56 and 8P57), at a resolution ranging from 1.85 to 1.60 Å (Tab. S1 in the SI), and in excess of ligand (PDBid: 7PHZ). Please notice that all the structure crystallizes in the same e P212121 space group (with the entire dimer/a.u.).