List of EC numbers (EC 1)

This list contains a list of EC numbers for the first group, EC 1, oxidoreductases, placed in numerical order as determined by the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology.

1 EC 1.1 Acting on the CH-OH group of donors
- 1.1 EC 1.1.1 With NAD or NADP as acceptor
- 1.2 EC 1.1.2 With a cytochrome as acceptor
- 1.3 EC 1.1.3 With oxygen as acceptor
- 1.4 EC 1.1.4 With a disulfide as acceptor
- 1.5 EC 1.1.5 With a quinone or similar compound as acceptor
- 1.6 EC 1.1.9 With a copper protein as acceptor
- 1.7 EC 1.1.98 With other, known, acceptors
- 1.8 EC 1.1.99 With other acceptors
2 EC 1.2 Acting on the aldehyde or oxo group of donors
- 2.1 EC 1.2.1 With NAD or NADP as acceptor
- 2.2 EC 1.2.2 With a cytochrome as acceptor
- 2.3 EC 1.2.3 With oxygen as acceptor
- 2.4 EC 1.2.4 With a disulfide as acceptor
- 2.5 EC 1.2.5 With FAD as acceptor
- 2.6 EC 1.2.7 With an iron-sulfur protein as acceptor
- 2.7 EC 1.2.99 With other acceptors
3 EC 1.3 Acting on the CH-CH group of donors
- 3.1 EC 1.3.1 With NAD or NADP as acceptor
- 3.2 EC 1.3.2 With a cytochrome as acceptor
- 3.3 EC 1.3.3 With oxygen as acceptor
- 3.4 EC 1.3.5 With a quinone or related compound as acceptor
- 3.5 EC 1.3.7 With an iron-sulfur protein as acceptor
- 3.6 EC 1.3.8 With an FAD as prosthetic group
- 3.7 EC 1.3.98 With FMN acceptor
- 3.8 EC 1.3.99 With other acceptors
4 EC 1.4 Acting on the CH-NH₂ group of donors
- 4.1 EC 1.4.1 With NAD or NADP as acceptor
- 4.2 EC 1.4.2 With a cytochrome as acceptor
- 4.3 EC 1.4.3 With oxygen as acceptor
- 4.4 EC 1.4.4 With a disulfide as acceptor
- 4.5 EC 1.4.5 With an iron-sulfur flavoprotein as acceptor
- 4.6 EC 1.4.7 With an iron-sulfur protein as acceptor
- 4.7 EC 1.4.9 With TTQ acceptors
- 4.8 EC 1.4.98 With tryptophan tryptophylquinone acceptors
- 4.9 EC 1.4.99 With other acceptors
5 EC 1.5 Acting on the CH-NH group of donors
- 5.1 EC 1.5.1 With NAD or NADP as acceptor
- 5.2 EC 1.5.3 With oxygen as acceptor
- 5.3 EC 1.5.4 With a disulfide as acceptor
- 5.4 EC 1.5.5 With a quinone or similar compound as acceptor
- 5.5 EC 1.5.7 With an iron-sulfur protein as acceptor
- 5.6 EC 1.5.8 With a flavin as acceptor
- 5.7 EC 1.5.99 With other acceptors
6 EC 1.6 Acting on NADH or NADPH
- 6.1 EC 1.6.1 With NAD or NADP as acceptor
- 6.2 EC 1.6.2 With a heme protein as acceptor
- 6.3 EC 1.6.3 With oxygen as acceptor
- 6.4 EC 1.6.4 With a disulfide as acceptor
- 6.5 EC 1.6.5 With a quinone or similar compound as acceptor
- 6.6 EC 1.6.6 With a nitrogenous group as acceptor
- 6.7 EC 1.6.7 With an iron-sulfur protein as acceptor
- 6.8 EC 1.6.8 With a flavin as acceptor
- 6.9 EC 1.6.99 With other acceptors
7 EC 1.7 Acting on other nitrogenous compounds as donors
- 7.1 EC 1.7.1 With NAD⁺ or NADP⁺ as acceptor
- 7.2 EC 1.7.2 With a cytochrome as acceptor
- 7.3 EC 1.7.3 With oxygen as acceptor
- 7.4 EC 1.7.5 With miscellaneous acceptora
- 7.5 EC 1.7.6 With hydrogen as acceptor
- 7.6 EC 1.7.7 With an iron-sulfur protein as acceptor
- 7.7 EC 1.7.99 With other acceptors
8 EC 1.8 Acting on a sulfur group of donors
- 8.1 EC 1.8.1 With NAD or NADP as acceptor
- 8.2 EC 1.8.2 With a cytochrome as acceptor
- 8.3 EC 1.8.3 With oxygen as acceptor
- 8.4 EC 1.8.4 With a disulfide as acceptor
- 8.5 EC 1.8.5 With a quinone or similar compound as acceptor
- 8.6 EC 1.8.6 With a nitrogenous group as acceptor
- 8.7 EC 1.8.7 With an iron-sulfur protein as acceptor
- 8.8 EC 1.8.98 With other, known, acceptors
- 8.9 EC 1.8.99 With other acceptors
9 EC 1.9 Acting on a heme group of donors
- 9.1 EC 1.9.3 With oxygen as acceptor
- 9.2 EC 1.9.6 With a nitrogenous group as acceptor
- 9.3 EC 1.9.99 With other acceptors
10 EC 1.10 Acting on diphenols and related substances as donors
- 10.1 EC 1.10.1 With NAD or NADP as acceptor
- 10.2 EC 1.10.2 With a cytochrome as acceptor
- 10.3 EC 1.10.3 With oxygen as acceptor
- 10.4 EC 1.10.99 With plastocyanin acceptors
- 10.5 EC 1.10.99 With other acceptors
11 EC 1.11 Acting on a peroxide as acceptor
- 11.1 EC 1.11.1 Peroxidases
- 11.2 EC 1.11.2 Peroxygenase
12 EC 1.12 Acting on hydrogen as donor
- 12.1 EC 1.12.1 With NAD or NADP as acceptor
- 12.2 EC 1.12.2 With a cytochrome as acceptor
- 12.3 EC 1.12.5 With a quinone or similar compound as acceptor
- 12.4 EC 1.12.7 With an iron-sulfur protein as acceptor
- 12.5 EC 1.12.98 With other known acceptors
- 12.6 EC 1.12.99 With other acceptors
13 EC 1.13 Acting on single donors with incorporation of molecular oxygen (oxygenases)
- 13.1 EC 1.13.1 (transferred to EC 1.13.11)
- 13.2 EC 1.13.11 With incorporation of two atoms of oxygen
- 13.3 EC 1.13.12 With incorporation of one atom of oxygen (internal monooxygenases or internal mixed function oxidases)
- 13.4 EC 1.13.99 Miscellaneous
14 EC 1.14 Acting on paired donors, with incorporation or reduction of molecular oxygen
- 14.1 EC 1.14.1 With NADH or NADPH as one donor (deleted sub-subclass)
- 14.2 EC 1.14.2 With ascorbate as one donor (deleted sub-subclass)
- 14.3 EC 1.14.3 With reduced pteridine as one donor (deleted sub-subclass)
- 14.4 EC 1.14.11 With 2-oxoglutarate as one donor, and incorporation of one atom each of oxygen into both donors
- 14.5 EC 1.14.12 With NADH or NADPH as one donor, and incorporation of two atoms of oxygen into one donor
- 14.6 EC 1.14.13 With NADH or NADPH as one donor, and incorporation of one atom of oxygen
- 14.7 EC 1.14.14 With reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen
- 14.8 EC 1.14.15 With reduced iron-sulfur protein as one donor, and incorporation of one atom of oxygen
- 14.9 EC 1.14.16 With reduced pteridine as one donor, and incorporation of one atom of oxygen
- 14.10 EC 1.14.17 With reduced ascorbate as one donor, and incorporation of one atom of oxygen
- 14.11 EC 1.14.18 With another compound as one donor, and incorporation of one atom of oxygen
- 14.12 EC 1.14.19 With oxidation of a pair of donors resulting in the reduction of molecular oxygen to two molecules of water
- 14.13 EC 1.14.20 With 2-oxoglutarate as one donor, and the other dehydrogenated
- 14.14 EC 1.14.21 With NADH or NADPH as one donor, and the other dehydrogenated
- 14.15 EC 1.14.99 Miscellaneous
15 EC 1.15 Acting on superoxide as acceptor
- 15.1 EC 1.15.1
16 EC 1.16 Oxidizing metal ions
- 16.1 EC 1.16.1 With NAD or NADP as acceptor
- 16.2 EC 1.16.3 With oxygen as acceptor
- 16.3 EC 1.16.5 With ascorbate as acceptor
- 16.4 EC 1.16.8 With flavin as acceptor
- 16.5 EC 1.16.9 With rusticyanin as acceptor
- 16.6 EC 1.16.98 With rusticyanin as acceptor
17 EC 1.17 Acting on CH or CH₂ groups
- 17.1 EC 1.17.1 With NAD or NADP as acceptor
- 17.2 EC 1.17.2 With MCD as acceptor
- 17.3 EC 1.17.3 With oxygen as acceptor
- 17.4 EC 1.17.4 With a disulfide as acceptor
- 17.5 EC 1.17.5 With a quinone or similar compound as acceptor
- 17.6 EC 1.17.7 With an iron-sulfur protein as acceptor
- 17.7 EC 1.17.99 With other acceptors
18 EC 1.18 Acting on iron-sulfur proteins as donors
- 18.1 EC 1.18.1 With NAD⁺ or NADP⁺ as acceptor
- 18.2 EC 1.18.2 With dinitrogen as acceptor (transferred to EC 1.18.6)
- 18.3 EC 1.18.3 With H⁺ as acceptor
- 18.4 EC 1.18.6 With dinitrogen as acceptor
- 18.5 EC 1.18.96 With other, known, acceptors
- 18.6 EC 1.18.99 With H⁺ as acceptor
19 EC 1.19 Acting on reduced flavodoxin as donor
- 19.1 EC 1.19.6 With dinitrogen as acceptor
20 EC 1.20 Acting on phosphorus or arsenic in donors
- 20.1 EC 1.20.1 Acting on phosphorus or arsenic in donors, with NAD⁺ as acceptor
- 20.2 EC 1.20.2 Acting on phosphorus or arsenic in donors, with NAD(P)⁺ as acceptor
- 20.3 EC 1.20.4 Acting on phosphorus or arsenic in donors, with disulfide as acceptor
- 20.4 EC 1.20.9 Acting on phosphorus or arsenic in donors, with azurin acceptors
- 20.5 EC 1.20.98 Acting on phosphorus or arsenic in donors, with other, known acceptors
- 20.6 EC 1.20.99 Acting on phosphorus or arsenic in donors, with other acceptors
21 EC 1.21 Acting on X-H and Y-H to form an X-Y bond
- 21.1 EC 1.21.3 With oxygen as acceptor
- 21.2 EC 1.21.4 With a disulfide as acceptor
- 21.3 EC 1.21.99 With other acceptors
22 EC 1.22 Acting on halogen in donors
- 22.1 EC 1.22.1 With NAD⁺ or NADP⁺ as acceptor
23 EC 1.97 Other oxidoreductases
- 23.1 EC 1.97.1
24 EC 1.98 Enzymes using H₂ as reductant
- 24.1 EC 1.98.1
25 EC 1.99 Other enzymes using O₂ as oxidant
- 25.1 EC 1.99.1 Hydroxylases (now covered by EC 1.14)
- 25.2 EC 1.99.2 Oxygenases (now covered by EC 1.13)

EC 1.1 Acting on the CH-OH group of donors[edit]

EC 1.1.1 With NAD or NADP as acceptor[edit]

EC 1.1.2 With a cytochrome as acceptor[edit]

EC 1.1.3 With oxygen as acceptor[edit]

EC 1.1.3.1: deleted, included in *EC 1.1.3.15
EC 1.1.3.2: now *EC 1.13.12.4
EC 1.1.3.3: malate oxidase
EC 1.1.3.4: glucose oxidase
EC 1.1.3.5: hexose oxidase
EC 1.1.3.6: cholesterol oxidase
EC 1.1.3.7: aryl-alcohol oxidase
EC 1.1.3.8: L-gulonolactone oxidase
EC 1.1.3.9: galactose oxidase
EC 1.1.3.10: pyranose oxidase
EC 1.1.3.11: L-sorbose oxidase
EC 1.1.3.12: pyridoxine 4-oxidase
EC 1.1.3.13: alcohol oxidase
EC 1.1.3.14: catechol oxidase (dimerizing)
EC 1.1.3.15: (S)-2-hydroxy-acid oxidase
EC 1.1.3.16: ecdysone oxidase
EC 1.1.3.17: choline oxidase
EC 1.1.3.18: Secondary-alcohol oxidase
EC 1.1.3.19: 4-hydroxymandelate oxidase
EC 1.1.3.20: long-chain-alcohol oxidase
EC 1.1.3.21: glycerol-3-phosphate oxidase
EC 1.1.3.22: now *EC 1.17.3.2
EC 1.1.3.23: Thiamine oxidase
EC 1.1.3.24: L-galactonolactone oxidase
EC 1.1.3.25: now included with *EC 1.1.99.18
EC 1.1.3.26: now *EC 1.21.3.2
EC 1.1.3.27: hydroxyphytanate oxidase
EC 1.1.3.28: nucleoside oxidase
EC 1.1.3.29: N-acylhexosamine oxidase
EC 1.1.3.30: polyvinyl-alcohol oxidase
EC 1.1.3.31: deleted
EC 1.1.3.32: now *EC 1.14.21.1
EC 1.1.3.33: now *EC 1.14.21.2
EC 1.1.3.34: now *EC 1.14.21.3
EC 1.1.3.35: now *EC 1.14.21.4
EC 1.1.3.36: now *EC 1.14.21.5
EC 1.1.3.37: D-arabinono-1,4-lactone oxidase
EC 1.1.3.38: vanillyl-alcohol oxidase
EC 1.1.3.39: nucleoside oxidase (H₂O₂-forming)
EC 1.1.3.40: D-mannitol oxidase
EC 1.1.3.41: xylitol oxidase
EC 1.1.3.42: prosolanapyrone-II oxidase
EC 1.1.3.43: paromamine 6'-oxidase
EC 1.1.3.44: 6-Hydroxyneomycin C oxidase

EC 1.1.4 With a disulfide as acceptor[edit]

EC 1.1.5 With a quinone or similar compound as acceptor[edit]

EC 1.1.5.1: deleted, see EC 1.1.99.18 cellobiose dehydrogenase (acceptor)
EC 1.1.5.2: quinoprotein glucose dehydrogenase
EC 1.1.5.3: glycerol-3-phosphate dehydrogenase (quinone)
EC 1.1.5.4: malate dehydrogenase (quinone)
EC 1.1.5.5: alcohol dehydrogenase (quinone)
EC 1.1.5.6: formate dehydrogenase-N
EC 1.1.5.7: cyclic alcohol dehydrogenase (quinone)
EC 1.1.5.8: quinate dehydrogenase (quinone)

EC 1.1.9 With a copper protein as acceptor[edit]

EC 1.1.9.1: alcohol dehydrogenase (azurin)

EC 1.1.98 With other, known, acceptors[edit]

EC 1.1.99 With other acceptors[edit]

EC 1.2 Acting on the aldehyde or oxo group of donors[edit]

EC 1.2.1 With NAD or NADP as acceptor[edit]

EC 1.2.2 With a cytochrome as acceptor[edit]

EC 1.2.7 With an iron-sulfur protein as acceptor[edit]

EC 1.2.99 With other acceptors[edit]

EC 1.3 Acting on the CH-CH group of donors[edit]

EC 1.3.1 With NAD or NADP as acceptor[edit]

EC 1.3.2 With a cytochrome as acceptor[edit]

EC 1.3.2.1: now EC 1.3.99.2
EC 1.3.2.2: now EC 1.3.99.3
EC 1.3.2.3: galactonolactone dehydrogenase

EC 1.3.3 With oxygen as acceptor[edit]

EC 1.3.5 With a quinone or related compound as acceptor[edit]

EC 1.3.7 With an iron-sulfur protein as acceptor[edit]

EC 1.3.8 With an FAD as prosthetic group[edit]

EC 1.3.98 With FMN acceptor[edit]

EC 1.3.98.1: dihydroorotate dehydrogenase (fumarate)

EC 1.3.99 With other acceptors[edit]

EC 1.4 Acting on the CH-NH₂ group of donors[edit]

EC 1.4.1 With NAD or NADP as acceptor[edit]

EC 1.4.2 With a cytochrome as acceptor[edit]

EC 1.4.2.1: glycine dehydrogenase (cytochrome)

EC 1.4.3 With oxygen as acceptor[edit]

EC 1.4.3.1: D-aspartate oxidase
EC 1.4.3.2: L-amino-acid oxidase
EC 1.4.3.3: D-amino-acid oxidase
EC 1.4.3.4: amine oxidase (flavin-containing)
EC 1.4.3.5: pyridoxamine-phosphate oxidase
EC 1.4.3.6: amine oxidase (copper-containing)
EC 1.4.3.7: D-glutamate oxidase
EC 1.4.3.8: ethanolamine oxidase
EC 1.4.3.9: deleted, included in *EC 1.4.3.4
EC 1.4.3.10: putrescine oxidase
EC 1.4.3.11: L-glutamate oxidase
EC 1.4.3.12: cyclohexylamine oxidase
EC 1.4.3.13: protein-lysine 6-oxidase
EC 1.4.3.14: L-lysine oxidase
EC 1.4.3.15: D-glutamate(D-aspartate) oxidase
EC 1.4.3.16: L-aspartate oxidase
EC 1.4.3.17: now *EC 1.3.3.10
EC 1.4.3.18: deleted, not approved
EC 1.4.3.19: glycine oxidase
EC 1.4.3.20: L-lysine 6-oxidase
EC 1.4.3.21: primary-amine oxidase
EC 1.4.3.22: diamine oxidase
EC 1.4.3.23: 7-chloro-L-tryptophan oxidase
EC 1.4.3.24: pseudooxynicotine oxidase

EC 1.4.4 With a disulfide as acceptor[edit]

EC 1.4.4.1: now EC 1.21.4.1
EC 1.4.4.2: glycine dehydrogenase (decarboxylating)

EC 1.4.5 With an iron-sulfur flavoprotein as acceptor[edit]

EC 1.4.5.1: D-amino acid dehydrogenase (quinone)

EC 1.4.7 With an iron-sulfur protein as acceptor[edit]

EC 1.4.7.1: glutamate synthase (ferredoxin)

EC 1.4.9 With TTQ acceptors[edit]

EC 1.4.98 With tryptophan tryptophylquinone acceptors[edit]

EC 1.4.98.1: methylamine dehydrogenase (amicyanin)

EC 1.4.99 With other acceptors[edit]

EC 1.5 Acting on the CH-NH group of donors[edit]

EC 1.5.1 With NAD or NADP as acceptor[edit]

EC 1.5.3 With oxygen as acceptor[edit]

EC 1.5.3.1: sarcosine oxidase
EC 1.5.3.2: N-methyl-L-amino-acid oxidase
EC 1.5.3.3: deleted
EC 1.5.3.4: N6-methyl-lysine oxidase
EC 1.5.3.5: (S)-6-hydroxynicotine oxidase
EC 1.5.3.6: (R)-6-hydroxynicotine oxidase
EC 1.5.3.7: L-pipecolate oxidase
EC 1.5.3.8: deleted, included in *EC 1.3.3.8
EC 1.5.3.9: now *EC 1.21.3.3
EC 1.5.3.10: dimethylglycine oxidase
EC 1.5.3.11: polyamine oxidase
EC 1.5.3.12: dihydrobenzophenanthridine oxidase
EC 1.5.3.13: N1-acetylpolyamine oxidase
EC 1.5.3.14: polyamine oxidase (propane-1,3-diamine-forming)
EC 1.5.3.15: N8-acetylspermidine oxidase (propane-1,3-diamine-forming)
EC 1.5.3.16: spermine oxidase
EC 1.5.3.17: non-specific polyamine oxidase
EC 1.5.3.18: L-saccharopine oxidase
EC 1.5.3.19: 4-methylaminobutanoate oxidase (formaldehyde-forming)
EC 1.5.3.20: N-alkylglycine oxidase
EC 1.5.3.21: 4-methylaminobutanoate oxidase (methylamine-forming)

EC 1.5.4 With a disulfide as acceptor[edit]

EC 1.5.4.1: pyrimidodiazepine synthase

EC 1.5.5 With a quinone or similar compound as acceptor[edit]

EC 1.5.5.1: electron-transferring-flavoprotein dehydrogenase

EC 1.5.7 With an iron-sulfur protein as acceptor[edit]

EC 1.5.7.1: methylenetetrahydrofolate reductase (ferredoxin)

EC 1.5.8 With a flavin as acceptor[edit]

EC 1.5.99 With other acceptors[edit]

EC 1.6 Acting on NADH or NADPH[edit]

EC 1.6.1 With NAD or NADP as acceptor[edit]

EC 1.6.2 With a heme protein as acceptor[edit]

EC 1.6.2.1: now EC 1.6.99.3
EC 1.6.2.2: cytochrome-b5 reductase
EC 1.6.2.3: deleted
EC 1.6.2.4: NADPH—hemoprotein reductase
EC 1.6.2.5: NADPH—cytochrome-c2 reductase
EC 1.6.2.6: leghemoglobin reductase

EC 1.6.3 With oxygen as acceptor[edit]

EC 1.6.3.1: NAD(P)H oxidase

EC 1.6.4 With a disulfide as acceptor[edit]

EC 1.6.5 With a quinone or similar compound as acceptor[edit]

EC 1.6.6 With a nitrogenous group as acceptor[edit]

EC 1.6.6.1: now *EC 1.7.1.1
EC 1.6.6.2: now *EC 1.7.1.2
EC 1.6.6.3: now *EC 1.7.1.3
EC 1.6.6.4: now *EC 1.7.1.4
EC 1.6.6.5: now *EC 1.7.99.3
EC 1.6.6.6: now *EC 1.7.1.5
EC 1.6.6.7: now *EC 1.7.1.6
EC 1.6.6.8: now *EC 1.7.1.7
EC 1.6.6.9: trimethylamine-N-oxide reductase
EC 1.6.6.10: now *EC 1.7.1.9
EC 1.6.6.11: now *EC 1.7.1.10
EC 1.6.6.12: now *EC 1.7.1.11
EC 1.6.6.13: now *EC 1.7.1.12

EC 1.6.7 With an iron-sulfur protein as acceptor[edit]

EC 1.6.7.1: now EC 1.18.1.2
EC 1.6.7.2: now EC 1.18.1.1

EC 1.6.8 With a flavin as acceptor[edit]

EC 1.6.8.1: now EC 1.5.1.29
EC 1.6.8.2: now EC 1.5.1.30

EC 1.6.99 With other acceptors[edit]

EC 1.6.99.1: NADPH dehydrogenase
EC 1.6.99.2: now *EC 1.6.5.2
EC 1.6.99.3: NADH dehydrogenase
EC 1.6.99.4: now *EC 1.18.1.2
EC 1.6.99.5: NADH dehydrogenase (quinone)
EC 1.6.99.6: NADPH dehydrogenase (quinone)
EC 1.6.99.7: now *EC 1.5.1.34
EC 1.6.99.8: now *EC 1.16.1.3
EC 1.6.99.9: now *EC 1.16.1.4
EC 1.6.99.10: deleted, included in *EC 1.6.99.7
EC 1.6.99.11: now *EC 1.16.1.5
EC 1.6.99.12: now *EC 1.16.1.6
EC 1.6.99.13: now *EC 1.16.1.7

EC 1.7 Acting on other nitrogenous compounds as donors[edit]

EC 1.7.1 With NAD⁺ or NADP⁺ as acceptor[edit]

EC 1.7.2 With a cytochrome as acceptor[edit]

EC 1.7.3 With oxygen as acceptor[edit]

EC 1.7.5 With miscellaneous acceptora[edit]

EC 1.7.6 With hydrogen as acceptor[edit]

EC 1.7.6.1: nitrite dismutase

EC 1.7.7 With an iron-sulfur protein as acceptor[edit]

EC 1.7.99 With other acceptors[edit]

EC 1.7.99.1: hydroxylamine reductase
EC 1.7.99.2: deleted
EC 1.7.99.3: included with *EC 1.7.2.1
EC 1.7.99.4: nitrate reductase
EC 1.7.99.5: deleted, now included with *EC 1.5.1.20
EC 1.7.99.6: nitrous-oxide reductase
EC 1.7.99.7: nitric-oxide reductase
EC 1.7.99.8: hydroxylamine oxidoreductase

EC 1.8 Acting on a sulfur group of donors[edit]

EC 1.8.1 With NAD or NADP as acceptor[edit]

EC 1.8.2 With a cytochrome as acceptor[edit]

EC 1.8.3 With oxygen as acceptor[edit]

EC 1.8.4 With a disulfide as acceptor[edit]

EC 1.8.5 With a quinone or similar compound as acceptor[edit]

EC 1.8.6 With a nitrogenous group as acceptor[edit]

EC 1.8.6.1: deleted, included in EC 2.5.1.18

EC 1.8.7 With an iron-sulfur protein as acceptor[edit]

EC 1.8.98 With other, known, acceptors[edit]

EC 1.8.99 With other acceptors[edit]

EC 1.9 Acting on a heme group of donors[edit]

EC 1.9.3 With oxygen as acceptor[edit]

EC 1.9.3.1: cytochrome-c oxidase
EC 1.9.3.2: included with EC 1.7.2.1

EC 1.9.6 With a nitrogenous group as acceptor[edit]

EC 1.9.6.1: nitrate reductase (cytochrome)

EC 1.9.99 With other acceptors[edit]

EC 1.9.99.1: iron—cytochrome-c reductase

EC 1.10 Acting on diphenols and related substances as donors[edit]

EC 1.10.1 With NAD or NADP as acceptor[edit]

EC 1.10.1.1: trans-acenaphthene-1,2-diol dehydrogenase

EC 1.10.2 With a cytochrome as acceptor[edit]

EC 1.10.3 With oxygen as acceptor[edit]

EC 1.10.3.1: catechol oxidase
EC 1.10.3.2: laccase
EC 1.10.3.3: L-ascorbate oxidase
EC 1.10.3.4: o-aminophenol oxidase
EC 1.10.3.5: 3-hydroxyanthranilate oxidase
EC 1.10.3.6: rifamycin-B oxidase
EC 1.10.3.7: now EC 1.21.3.4
EC 1.10.3.8: now EC 1.21.3.5
EC 1.10.3.9: photosystem II
EC 1.10.3.10: ubiquinol oxidase (H⁺-transporting)
EC 1.10.3.11: ubiquinol oxidase
EC 1.10.3.12: menaquinol oxidase (H⁺-transporting)

EC 1.10.99 With plastocyanin acceptors[edit]

EC 1.10.9.1: plastoquinol---plastocyanin reductase

EC 1.10.99 With other acceptors[edit]

EC 1.11 Acting on a peroxide as acceptor[edit]

EC 1.11.1 Peroxidases[edit]

EC 1.11.2 Peroxygenase[edit]

EC 1.12 Acting on hydrogen as donor[edit]

EC 1.12.1 With NAD or NADP as acceptor[edit]

EC 1.12.2 With a cytochrome as acceptor[edit]

EC 1.12.2.1: cytochrome-c3 hydrogenase

EC 1.12.5 With a quinone or similar compound as acceptor[edit]

EC 1.12.5.1: hydrogen:quinone oxidoreductase

EC 1.12.7 With an iron-sulfur protein as acceptor[edit]

EC 1.12.7.1: now EC 1.18.99.1
EC 1.12.7.2: ferredoxin hydrogenase

EC 1.12.98 With other known acceptors[edit]

EC 1.12.99 With other acceptors[edit]

EC 1.12.99.1: now *EC 1.12.98.1
EC 1.12.99.2: deleted, composed of *EC 1.12.98.3 and *EC 1.8.98.1
EC 1.12.99.3: now *EC 1.12.5.1
EC 1.12.99.4: now *EC 1.12.98.2
EC 1.12.99.5: identical to *EC 1.13.11.47
EC 1.12.99.6: hydrogenase (acceptor)

EC 1.13 Acting on single donors with incorporation of molecular oxygen (oxygenases)[edit]

EC 1.13.1 (transferred to EC 1.13.11)[edit]

EC 1.13.11 With incorporation of two atoms of oxygen[edit]

EC 1.13.12 With incorporation of one atom of oxygen (internal monooxygenases or internal mixed function oxidases)[edit]

EC 1.13.99 Miscellaneous[edit]

EC 1.14 Acting on paired donors, with incorporation or reduction of molecular oxygen[edit]

EC 1.14.1 With NADH or NADPH as one donor (deleted sub-subclass)[edit]

EC 1.14.1.1: now EC 1.14.14.1
EC 1.14.1.2: now EC 1.14.13.9
EC 1.14.1.3: deleted, covered by EC 1.14.99.7, EC 5.4.99.7
EC 1.14.1.4: now EC 1.14.99.2
EC 1.14.1.5: now EC 1.14.13.5
EC 1.14.1.6: now EC 1.14.15.4
EC 1.14.1.7: now EC 1.14.99.9
EC 1.14.1.8: now EC 1.14.99.10
EC 1.14.1.9: deleted
EC 1.14.1.10: now EC 1.14.99.11
EC 1.14.1.11: deleted

EC 1.14.2 With ascorbate as one donor (deleted sub-subclass)[edit]

EC 1.14.2.1: now EC 1.14.17.1
EC 1.14.2.2: now EC 1.13.11.27

EC 1.14.3 With reduced pteridine as one donor (deleted sub-subclass)[edit]

EC 1.14.3.1: now EC 1.14.16.1

EC 1.14.11 With 2-oxoglutarate as one donor, and incorporation of one atom each of oxygen into both donors[edit]

EC 1.14.12 With NADH or NADPH as one donor, and incorporation of two atoms of oxygen into one donor[edit]

EC 1.14.13 With NADH or NADPH as one donor, and incorporation of one atom of oxygen[edit]

EC 1.14.14 With reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen[edit]

EC 1.14.14.1: unspecific monooxygenase
EC 1.14.14.2: deleted, included in EC 1.14.14.1
EC 1.14.14.3: alkanal monooxygenase (FMN-linked)
EC 1.14.14.4: deleted, identical to EC 1.14.15.7
EC 1.14.14.5: alkanesulfonate monooxygenase
EC 1.14.14.6: Now EC 1.14.13.111
EC 1.14.14.7: tryptophan 7-halogenase
EC 1.14.14.8: anthranilate 3-monooxygenase (FAD)
EC 1.14.14.9: 4-hydroxyphenylacetate 3-monooxygenase
EC 1.14.14.10: nitrilotriacetate monooxygenase
EC 1.14.14.11: styrene monooxygenase
EC 1.14.14.12: 3-hydroxy-9,10-secoandrosta-1,3,5(10)-triene-9,17-dione monooxygenase
EC 1.14.14.13: 4-(gamma-L-glutamylamino)butanoyl-(BtrI acyl-carrier protein) monooxygenase

EC 1.14.15 With reduced iron-sulfur protein as one donor, and incorporation of one atom of oxygen[edit]

EC 1.14.16 With reduced pteridine as one donor, and incorporation of one atom of oxygen[edit]

EC 1.14.17 With reduced ascorbate as one donor, and incorporation of one atom of oxygen[edit]

EC 1.14.17.1: dopamine b-monooxygenase
EC 1.14.17.2: deleted, included in EC 1.14.18.1
EC 1.14.17.3: peptidylglycine monooxygenase
EC 1.14.17.4: aminocyclopropanecarboxylate oxidase

EC 1.14.18 With another compound as one donor, and incorporation of one atom of oxygen[edit]

EC 1.14.19 With oxidation of a pair of donors resulting in the reduction of molecular oxygen to two molecules of water[edit]

EC 1.14.20 With 2-oxoglutarate as one donor, and the other dehydrogenated[edit]

EC 1.14.21 With NADH or NADPH as one donor, and the other dehydrogenated[edit]

EC 1.14.99 Miscellaneous[edit]

EC 1.15 Acting on superoxide as acceptor[edit]

EC 1.15.1[edit]

EC 1.16 Oxidizing metal ions[edit]

EC 1.16.1 With NAD or NADP as acceptor[edit]

EC 1.16.3 With oxygen as acceptor[edit]

EC 1.16.3.1: ferroxidase

EC 1.16.5 With ascorbate as acceptor[edit]

EC 1.16.5.1: ascorbate ferrireductase (transmembrane)

EC 1.16.8 With flavin as acceptor[edit]

EC 1.16.8.1: cob(II)yrinic acid a,c-diamide reductase

EC 1.16.9 With rusticyanin as acceptor[edit]

EC 1.16.9.1: iron:rusticyanin reductase

EC 1.16.98 With rusticyanin as acceptor[edit]

EC 1.16.98.1: Now EC 1.16.9.1

EC 1.17 Acting on CH or CH₂ groups[edit]

EC 1.17.1 With NAD or NADP as acceptor[edit]

EC 1.17.2 With MCD as acceptor[edit]

EC 1.17.3 With oxygen as acceptor[edit]

EC 1.17.4 With a disulfide as acceptor[edit]

EC 1.17.5 With a quinone or similar compound as acceptor[edit]

EC 1.17.7 With an iron-sulfur protein as acceptor[edit]

EC 1.17.99 With other acceptors[edit]

EC 1.18 Acting on iron-sulfur proteins as donors[edit]

EC 1.18.1 With NAD⁺ or NADP⁺ as acceptor[edit]

EC 1.18.2 With dinitrogen as acceptor (transferred to EC 1.18.6)[edit]

EC 1.18.2.1: now EC 1.18.6.1

EC 1.18.3 With H⁺ as acceptor[edit]

EC 1.18.3.1: now EC 1.18.99.1

EC 1.18.6 With dinitrogen as acceptor[edit]

EC 1.18.6.1: nitrogenase

EC 1.18.96 With other, known, acceptors[edit]

EC 1.18.96.1: now EC 1.15.1.2

EC 1.18.99 With H⁺ as acceptor[edit]

EC 1.18.99.1: now EC 1.12.7.2

EC 1.19 Acting on reduced flavodoxin as donor[edit]

EC 1.19.6 With dinitrogen as acceptor[edit]

EC 1.19.6.1: nitrogenase (flavodoxin)

EC 1.20 Acting on phosphorus or arsenic in donors[edit]

EC 1.20.1 Acting on phosphorus or arsenic in donors, with NAD⁺ as acceptor[edit]

EC 1.20.1.1: phosphonate dehydrogenase

EC 1.20.2 Acting on phosphorus or arsenic in donors, with NAD(P)⁺ as acceptor[edit]

EC 1.20.2.1: arsenate reductase (cytochrome c)

EC 1.20.4 Acting on phosphorus or arsenic in donors, with disulfide as acceptor[edit]

EC 1.20.9 Acting on phosphorus or arsenic in donors, with azurin acceptors[edit]

EC 1.20.9.1: arsenate reductase (azurin)

EC 1.20.98 Acting on phosphorus or arsenic in donors, with other, known acceptors[edit]

EC 1.20.98.1: Now EC 1.20.9.1

EC 1.20.99 Acting on phosphorus or arsenic in donors, with other acceptors[edit]

EC 1.20.99.1: arsenate reductase (donor)

EC 1.21 Acting on X-H and Y-H to form an X-Y bond[edit]

EC 1.21.3 With oxygen as acceptor[edit]

EC 1.21.4 With a disulfide as acceptor[edit]

EC 1.21.99 With other acceptors[edit]

EC 1.21.99.1: b-cyclopiazonate dehydrogenase

EC 1.22 Acting on halogen in donors[edit]

EC 1.22.1 With NAD⁺ or NADP⁺ as acceptor[edit]

EC 1.22.1.1: iodotyrosine deiodinase

EC 1.97 Other oxidoreductases[edit]

EC 1.97.1[edit]

EC 1.97.1.1: chlorate reductase
EC 1.97.1.2: pyrogallol hydroxytransferase
EC 1.97.1.3: sulfur reductase
EC 1.97.1.4: (formate-C-acetyltransferase)-activating enzyme
EC 1.97.1.5: now *EC 1.20.4.1
EC 1.97.1.6: now *EC 1.20.99.1
EC 1.97.1.7: now *EC 1.20.4.2
EC 1.97.1.8: tetrachloroethene reductive dehalogenase
EC 1.97.1.9: selenate reductase
EC 1.97.1.10: thyroxine 5'-deiodinase
EC 1.97.1.11: thyroxine 5-deiodinase
EC 1.97.1.12: photosystem I

EC 1.98 Enzymes using H₂ as reductant[edit]

EC 1.98.1[edit]

EC 1.98.1.1: now EC 1.18.99.1

EC 1.99 Other enzymes using O₂ as oxidant[edit]

EC 1.99.1 Hydroxylases (now covered by EC 1.14)[edit]

EC 1.99.1.1: deleted, now *EC 1.14.14.1
EC 1.99.1.2: deleted, now *EC 1.14.16.1
EC 1.99.1.3: deleted
EC 1.99.1.4: deleted
EC 1.99.1.5: deleted, now *EC 1.14.13.9
EC 1.99.1.6: deleted
EC 1.99.1.7: deleted, now *EC 1.14.15.4
EC 1.99.1.8: deleted
EC 1.99.1.9: deleted, now *EC 1.14.99.9
EC 1.99.1.10: deleted
EC 1.99.1.11: deleted, now *EC 1.14.99.10
EC 1.99.1.12: deleted
EC 1.99.1.13: deleted, covered by *EC 1.14.99.7 and *EC 5.4.99.7
EC 1.99.1.14: deleted, now *EC 1.13.11.27

EC 1.99.2 Oxygenases (now covered by EC 1.13)[edit]

EC 1.99.2.1: deleted, now *EC 1.13.11.12
EC 1.99.2.2: deleted, now *EC 1.13.11.1
EC 1.99.2.3: deleted, now *EC 1.13.11.3
EC 1.99.2.4: deleted, now *EC 1.13.11.4
EC 1.99.2.5: deleted, now *EC 1.13.11.5
EC 1.99.2.6: deleted, now *EC 1.13.99.1

v t e Enzymes

Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Catalytically perfect enzyme Coenzyme Cofactor Enzyme catalysis Enzyme kinetics Lineweaver–Burk plot Michaelis–Menten kinetics

Regulation	Allosteric regulation Cooperativity Enzyme inhibitor

Classification	EC number Enzyme superfamily Enzyme family List of enzymes

Types	EC1 Oxidoreductases (list) EC2 Transferases (list) EC3 Hydrolases (list) EC4 Lyases (list) EC5 Isomerases (list) EC6 Ligases (list)

v t e Oxidoreductases: alcohol oxidoreductases (EC 1.1)

1.1.1: NAD/NADP acceptor	3-hydroxyacyl-CoA dehydrogenase 3-hydroxybutyryl-CoA dehydrogenase Alcohol dehydrogenase Aldo-keto reductase 1A1 1B1 1B10 1C1 1C3 1C4 7A2 Aldose reductase Beta-Ketoacyl ACP reductase Carbohydrate dehydrogenases Carnitine dehydrogenase D-malate dehydrogenase (decarboxylating) DXP reductoisomerase Glucose-6-phosphate dehydrogenase Glycerol-3-phosphate dehydrogenase HMG-CoA reductase IMP dehydrogenase Isocitrate dehydrogenase Lactate dehydrogenase L-threonine dehydrogenase L-xylulose reductase Malate dehydrogenase Malate dehydrogenase (decarboxylating) Malate dehydrogenase (NADP+) Malate dehydrogenase (oxaloacetate-decarboxylating) Malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) Phosphogluconate dehydrogenase Sorbitol dehydrogenase Hydroxysteroid dehydrogenase: 3 Beta 3-beta-HSD NSDHL 11 Beta HSD11B1 HSD11B2 17 Beta

1.1.2: cytochrome acceptor	D-lactate dehydrogenase (cytochrome) D-lactate dehydrogenase (cytochrome c-553) Mannitol dehydrogenase (cytochrome)

1.1.3: oxygen acceptor	Glucose oxidase L-gulonolactone oxidase Xanthine oxidase

1.1.4: disulfide as acceptor	Vitamin K epoxide reductase Vitamin-K-epoxide reductase (warfarin-insensitive)

1.1.5: quinone/similar acceptor	Malate dehydrogenase (quinone) Quinoprotein glucose dehydrogenase

1.1.99: other acceptors	Choline dehydrogenase L2HGDH

v t e Aldehyde/oxo oxidoreductases (EC 1.2)

1.2.1: NAD or NADP	Aldehyde dehydrogenase Acetaldehyde dehydrogenase Long-chain-aldehyde dehydrogenase

1.2.2: cytochrome	Formate dehydrogenase (cytochrome)

1.2.3: oxygen	Aldehyde oxidase

1.2.4: disulfide	Oxoglutarate dehydrogenase complex Pyruvate dehydrogenase Branched-chain alpha-keto acid dehydrogenase complex BCKDHA BCKDHB DBT DLD

1.2.7: iron-sulfur protein	Pyruvate synthase

v t e Oxidoreductases: CH–CH oxidoreductases (EC 1.3)

1.3.1: NAD/NADP acceptor	Enoyl-acyl carrier protein reductase/Enoyl ACP reductase 7-Dehydrocholesterol reductase Biliverdin reductase 2,4 Dienoyl-CoA reductase Dihydroxymethyloxo-tetrahydroquinoline dehydrogenase

1.3.3: Oxygen acceptor	Dihydroorotate dehydrogenase Coproporphyrinogen III oxidase Protoporphyrinogen oxidase Bilirubin oxidase Acyl-CoA oxidase Dihydrouracil oxidase Tetrahydroberberine oxidase Secologanin synthase Tryptophan alpha,beta-oxidase Pyrroloquinoline-quinone synthase L-galactonolactone oxidase

1.3.5: Quinone	Succinate dehydrogenase SDHA SDHB SDHC SDHD

1.3.99: Other acceptors	Fumarate reductase Butyryl-CoA dehydrogenase Acyl CoA dehydrogenase ACADSB ACADS 5α-reductase SRD5A1 SRD5A2 SRD5A3 Glutaryl-CoA dehydrogenase Isovaleryl coenzyme A dehydrogenase 3-oxo-5beta-steroid 4-dehydrogenase

v t e CH-NH₂ oxidoreductases (EC 1.4) - primarily amino acid oxidoreductases

1.4.1: NAD/NADP acceptor	Glutamate dehydrogenase GLUD1 GLUD2 Glutamate synthase (NADPH)

1.4.3: oxygen acceptor	D-amino acid oxidase Amine oxidase (Copper-containing (Lysyl Diamine Primary-amine)) (Flavin-containing (Monoamine)))

1.4.4: disulfide acceptor	Glycine cleavage system

1.4.99: other acceptors	D-amino acid dehydrogenase Amine dehydrogenase

v t e Oxidoreductases: CH-NH (EC 1.5)

1.5.1: NAD or NADP acceptor	Dihydrofolate reductase Saccharopine dehydrogenase Methylenetetrahydrofolate reductase

1.5.3: oxygen acceptor	Dihydrobenzophenanthridine oxidase Sarcosine oxidase Proline oxidase

1.5.5: quinone acceptor	Electron-transferring-flavoprotein dehydrogenase

1.5.99	Sarcosine dehydrogenase Cytokinin dehydrogenase

v t e Oxidoreductases: NADH or NADPH (EC 1.6)

1.6.1: NAD/NADP	NAD(P)⁺ transhydrogenase (Si-specific) NAD(P)⁺ transhydrogenase (Re/Si-specific)

1.6.2: Heme	Methemoglobin reductase NADPH—hemoprotein reductase/Cytochrome P450 reductase NADPH—cytochrome-c2 reductase Leghemoglobin reductase

1.6.3: Oxygen	NADPH oxidase P91-PHOX Neutrophil cytosolic factor 1 Neutrophil cytosolic factor 2 Neutrophil cytosolic factor 4 dual oxidase Dual oxidase 1 Dual oxidase 2

1.6.5: Quinone or similar	NADH dehydrogenase

1.6.6: Nitrogenous group	Trimethylamine-N-oxide reductase

1.6.99: other	NADH dehydrogenase (quinone)

v t e Oxidoreductases: nitrogenous donor (EC 1.7)

1.7.1	GMP reductase

1.7.2	Nitrite reductase (NO-forming)

1.7.3	Urate oxidase

1.7.7	Ferredoxin—nitrite reductase

1.7.99	Hydroxylamine reductase

v t e Oxidoreductases: sulfur oxidoreductases (EC 1.8)

1.8.1: NAD or NADP	Dihydrolipoamide dehydrogenase Glutathione reductase Thioredoxin reductase

1.8.2: cytochrome	Sulfite dehydrogenase Thiosulfate dehydrogenase

1.8.3: oxygen	Sulfite oxidase

1.8.4: disulfide	Glutathione—homocystine transhydrogenase

1.8.5: quinone	Glutathione dehydrogenase (ascorbate)

1.8.98: Other, known	CoB—CoM heterodisulfide reductase

1.8.99: Other	Sulfite reductase

v t e Oxidoreductases: diphenol family (EC 1.10)

1.10.1	Trans-acenaphthene-1,2-diol dehydrogenase

1.10.2	Coenzyme Q - cytochrome c reductase

1.10.3	Catechol oxidase Laccase

1.10.99	Cytochrome b6f complex

Other	Alternative oxidase

v t e Oxidoreductases: peroxidases (EC 1.11)

1.11.1.1-14	Catalase Cytochrome c peroxidase Eosinophil peroxidase Glutathione peroxidase GPX 1 2 3 4 5 6 7 8 Horseradish peroxidase Lactoperoxidase Myeloperoxidase Thyroid peroxidase Deiodinase Iodothyronine deiodinase Iodotyrosine deiodinase

1.11.1.15 (peroxiredoxin)	1 2 3 4 5 6

v t e Oxidoreductases: monooxygenases (EC 1.13)

1.13.11: two atoms of oxygen	lipoxygenase: Arachidonate 5-lipoxygenase Arachidonate 12-lipoxygenase/ALOX12 Arachidonate 8-lipoxygenase Arachidonate 15-lipoxygenase/ALOX15 Linoleate 11-lipoxygenase other dioxygenase: Catechol dioxygenase Homogentisate 1,2-dioxygenase Cysteine dioxygenase 4-Hydroxyphenylpyruvate dioxygenase Indoleamine 2,3-dioxygenase Chlorite dismutase

1.13.12: one atom of oxygen	Firefly luciferase

1.13.99: other	Inositol oxygenase

v t e Oxidoreductases: dioxygenases, including steroid hydroxylases (EC 1.14)

1.14.11: 2-oxoglutarate	Prolyl hydroxylase Lysyl hydroxylase

1.14.13: NADH or NADPH	Flavin-containing monooxygenase FMO1 FMO2 FMO3 FMO4 FMO5 Nitric oxide synthase NOS1 NOS2 NOS3 Cholesterol 7 alpha-hydroxylase Methane monooxygenase 3A4 Lanosterol 14 alpha-demethylase 24-hydroxycholesterol 7α-hydroxylase

1.14.14: reduced flavin or flavoprotein	19A1 2D6 2E1

1.14.15: reduced iron-sulfur protein	11B1 11B2 11A1

1.14.16: reduced pteridine (BH4 dependent)	Phenylalanine hydroxylase Tyrosine hydroxylase Tryptophan hydroxylase

1.14.17: reduced ascorbate	Dopamine beta-hydroxylase

1.14.18-19: other	Tyrosinase Stearoyl-CoA desaturase-1

1.14.99 - miscellaneous	Cyclooxygenase Heme oxygenase (HMOX1) Squalene monooxygenase 17A1 21A2

v t e Other oxidoreductases (EC 1.15-1.21)

1.15: Acting on superoxide as acceptor	Superoxide dismutase SOD1 SOD2 SOD3

1.16: Oxidizing metal ions	Ceruloplasmin

1.17: Acting on CH or CH2 groups	Xanthine oxidase Ribonucleotide reductase 4-Hydroxy-3-methylbut-2-enyl diphosphate reductase

1.18: Acting on iron-sulfur proteins as donors	Nitrogenase

1.19: Acting on reduced flavodoxin as donor	Nitrogenase (flavodoxin)

1.20: Acting on phosphorus or arsenic in donors	Glutaredoxin GLRX GLRX2 GLRX3 GLRX5

1.21: Acting on X-H and Y-H to form an X-Y bond	Isopenicillin N synthase Columbamine oxidase Reticuline oxidase Sulochrin oxidase (+)-bisdechlorogeodin-forming (-)-bisdechlorogeodin-forming Aureusidin synthase Tetrahydrocannabinolic acid synthase Cannabidiolic acid synthase Dichlorochromopyrrolate synthase