_EC 6.3.4.- Other carbon--nitrogen ligases. 240 PDB entries  
EC 6.-.-.- Ligases. [1,580 PDB entries]
EC 6.3.-.- Forming carbon-nitrogen bonds. [793 PDB entries]
EC 6.3.4.- Other carbon--nitrogen ligases. [240 PDB entries]    
EC 6.3.4.1 Transferred entry: 6.3.5.2. [-]
EC 6.3.4.2 Ctp synthase (glutamine hydrolyzing). [12 PDB entries]
EC 6.3.4.3 Formate--tetrahydrofolate ligase. [22 PDB entries]
EC 6.3.4.4 Adenylosuccinate synthase. [44 PDB entries]
EC 6.3.4.5 Argininosuccinate synthase. [14 PDB entries]
EC 6.3.4.6 Urea carboxylase. [-]
EC 6.3.4.7 Ribose-5-phosphate--ammonia ligase. [-]
EC 6.3.4.8 Imidazoleacetate--phosphoribosyldiphosphate ligase. [-]
EC 6.3.4.9 Biotin--[methylmalonyl-CoA-carboxytransferase] ligase. [-]
EC 6.3.4.10 Biotin--[propionyl-CoA-carboxylase (ATP-hydrolyzing)] ligase. [-]
EC 6.3.4.11 Biotin--[methylcrotonoyl-CoA-carboxylase] ligase. [-]
EC 6.3.4.12 Glutamate--methylamine ligase. [-]
EC 6.3.4.13 Phosphoribosylamine--glycine ligase. [30 PDB entries]
EC 6.3.4.14 Biotin carboxylase. [63 PDB entries]
EC 6.3.4.15 Biotin--[acetyl-CoA-carboxylase] ligase. [17 PDB entries]
EC 6.3.4.16 Carbamoyl-phosphate synthase (ammonia). [1 PDB entries]
EC 6.3.4.17 Formate--dihydrofolate ligase. [-]
EC 6.3.4.18 5-(carboxyamino)imidazole ribonucleotide synthase. [5 PDB entries]
EC 6.3.4.19 tRNA(Ile)-lysidine synthetase. [6 PDB entries]
EC 6.3.4.20 7-cyano-7-deazaguanine synthase. [2 PDB entries]
EC 6.3.4.21 Nicotinate phosphoribosyltransferase. [12 PDB entries]
EC 6.3.4.22 tRNA(Ile)(2)-agmatinylcytidine synthase. [4 PDB entries]
EC 6.3.4.23 Formate--phosphoribosylaminoimidazolecarboxamide ligase. [8 PDB entries]

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