To confirm effective cross-linking of HheG D114C crystals with BMOE, the crystal structure of respective CLECs was solved at 2.7 Å resolution (PDB-ID: 7QY3). Variant D114C crystallized in the same trigonal space group P3121 as wild-type HheG. Moreover, unit cell parameters were also similar to that of the wild-type enzyme (Table ). Analysis via PDBePISA webserver confirmed that crystals of variant D114C exhibited the same crystal contacts (axial and tangential interface, see Figure ) as wildtype HheG except for the mutated residue 114, where an aspartic acid was exchanged by a cysteine.