_EC 5.4.-.- Intramolecular transferases (mutases). 374 PDB entries  
EC 5.-.-.- Isomerases. [1,984 PDB entries]
EC 5.4.-.- Intramolecular transferases (mutases). [374 PDB entries]    
EC 5.4.1.- Transferring acyl groups. [3 PDB entries]
EC 5.4.2.- Phosphotransferases (phosphomutases). [136 PDB entries]
EC 5.4.3.- Transferring amino groups. [36 PDB entries]
EC 5.4.4.- Transferring hydroxy groups. [13 PDB entries]
EC 5.4.99.- Transferring other groups. [186 PDB entries]