_EC 5.1.1.- Acting on amino acids and derivatives. 118 PDB entries  
EC 5.-.-.- Isomerases. [2,328 PDB entries]
EC 5.1.-.- Racemases and epimerases. [322 PDB entries]
EC 5.1.1.- Acting on amino acids and derivatives. [118 PDB entries]    
EC 5.1.1.1 Alanine racemase. [50 PDB entries]
EC 5.1.1.2 Methionine racemase. [-]
EC 5.1.1.3 Glutamate racemase. [28 PDB entries]
EC 5.1.1.4 Proline racemase. [4 PDB entries]
EC 5.1.1.5 Lysine racemase. [1 PDB entries]
EC 5.1.1.6 Threonine racemase. [-]
EC 5.1.1.7 Diaminopimelate epimerase. [12 PDB entries]
EC 5.1.1.8 4-hydroxyproline epimerase. [1 PDB entries]
EC 5.1.1.9 Arginine racemase. [-]
EC 5.1.1.10 Amino-acid racemase. [9 PDB entries]
EC 5.1.1.11 Phenylalanine racemase (ATP-hydrolyzing). [1 PDB entries]
EC 5.1.1.12 Ornithine racemase. [-]
EC 5.1.1.13 Aspartate racemase. [1 PDB entries]
EC 5.1.1.14 Nocardicin-A epimerase. [-]
EC 5.1.1.15 2-aminohexano-6-lactam racemase. [3 PDB entries]
EC 5.1.1.16 Protein-serine epimerase. [-]
EC 5.1.1.17 Isopenicillin-N epimerase. [-]
EC 5.1.1.18 Serine racemase. [8 PDB entries]
EC 5.1.1.19 O-ureido-serine racemase. [-]
EC 5.1.1.n1 L-Ala-D/L-Glu epimerase. [-]

[-] signifies that there are no PDB entries for the given enzyme subclass