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. All official information is tabulated at the website of the committee. The database is developed and maintained by Andrew McDonald.

EC 1.1 Acting on the CH-OH group of donors

EC 1.1.1 With Nicotinamide adenine dinucleotide or NADP as acceptor

EC 1.1.2 With a cytochrome as acceptor

EC 1.1.3 With oxygen as acceptor

EC 1.1.4 With a disulfide as acceptor

EC 1.1.5 With a quinone or similar compound as acceptor

EC 1.1.9 With a copper protein as acceptor

EC 1.1.98 With other, known, acceptors

EC 1.1.99 With unknown physiological acceptors

EC 1.2 Acting on the aldehyde or oxo group of donors

EC 1.2.1 With NAD+ or NADP+ as acceptor

EC 1.2.2 With a cytochrome as acceptor

EC 1.2.3 With oxygen as acceptor

EC 1.2.4 With a disulfide as acceptor

EC 1.2.5 With a quinone or similar compound as acceptor

EC 1.2.7 With an iron–sulfur protein as acceptor

EC 1.2.99: With unknown physiological acceptors

EC 1.3 Acting on the CH-CH group of donors

EC 1.3.1 With NAD+ or NADP+ as acceptor

EC 1.3.2 With a cytochrome as acceptor

EC 1.3.3 With oxygen as acceptor

EC 1.3.5 With a quinone or related compound as acceptor

EC 1.3.7 With an iron–sulfur protein as acceptor

EC 1.3.8 With a flavin as acceptor

EC 1.3.98 With FMN acceptor

EC 1.3.99 With unknown physiological acceptors

EC 1.4 Acting on the CH-NH2 group of donors

EC 1.4.1 With NAD+ or NADP+ as acceptor

EC 1.4.2 With a cytochrome as acceptor

EC 1.4.3 With oxygen as acceptor

EC 1.4.4 With a disulfide as acceptor

EC 1.4.5 With a quinone or other compound as acceptor

EC 1.4.7 With an iron–sulfur protein as acceptor

EC 1.4.9 With a copper protein as acceptor

EC 1.4.98 With tryptophan tryptophylquinone acceptors

EC 1.4.99 With unknown physiological acceptors

EC 1.5 Acting on the CH-NH group of donors

EC 1.5.1 With NAD+ or NADP+ as acceptor

EC 1.5.3 With oxygen as acceptor

EC 1.5.4 With a disulfide as acceptor

EC 1.5.5 With a quinone or similar compound as acceptor

EC 1.5.7 With an iron–sulfur protein as acceptor

EC 1.5.8 With a flavin or flavoprotein as acceptor

EC 1.5.98 With other, known, physiological acceptors

EC 1.5.99 With unknown physiological acceptors

EC 1.6 Acting on NADH or NADPH

EC 1.6.1 With NAD or NADP as acceptor

EC 1.6.2 With a heme protein as acceptor

EC 1.6.3 With oxygen as acceptor

EC 1.6.4 With a disulfide as acceptor (deleted sub-class)

EC 1.6.5 With a quinone or similar compound as acceptor

EC 1.6.6 With a nitrogenous group as acceptor

EC 1.6.7 With an iron–sulfur protein as acceptor (deleted sub-subclass)

EC 1.6.8 With a flavin as acceptor (deleted sub-subclass)

EC 1.6.99 With unknown physiological acceptors

EC 1.7 Acting on other nitrogenous compounds as donors

EC 1.7.1 With NAD+ or NADP+ as acceptor

EC 1.7.2 With a cytochrome as acceptor

EC 1.7.3 With oxygen as acceptor

EC 1.7.5 With a quinone or similar compound as acceptor

EC 1.7.6 With a nitrogenous group as acceptor

EC 1.7.7 With an iron–sulfur protein as acceptor

EC 1.7.99 With other acceptors

EC 1.8 Acting on a sulfur group of donors

EC 1.8.1 With NAD+ or NADP+ as acceptor

EC 1.8.2 With a cytochrome as acceptor

EC 1.8.3 With oxygen as acceptor

EC 1.8.4 With a disulfide as acceptor

EC 1.8.5 With a quinone or similar compound as acceptor

EC 1.8.6 With a nitrogenous group as acceptor (deleted sub-subclass)

EC 1.8.7 With an iron–sulfur protein as acceptor

EC 1.8.98 With other, known, acceptors

EC 1.8.99 With other acceptors

EC 1.9 Acting on a heme group of donors

EC 1.9.3 With oxygen as acceptor

EC 1.9.6 With a nitrogenous group as acceptor

EC 1.9.98 With other, known, physiological acceptors

EC 1.9.99 With other acceptors

EC 1.10 Acting on diphenols and related substances as donors

EC 1.10.1 With NAD+ or NADP+ as acceptor

EC 1.10.2 With a cytochrome as acceptor

EC 1.10.3 With oxygen as acceptor

EC 1.10.5 With a quinone or related compound as acceptor

EC 1.10.9 With a copper protein as acceptor

EC 1.10.99 With unknown physiological acceptors

EC 1.11 Acting on a peroxide as acceptor

EC 1.11.1 Peroxidases

EC 1.11.2 Peroxygenase

EC 1.12 Acting on hydrogen as donor

EC 1.12.1 With NAD+ or NADP+ as acceptor

EC 1.12.2 With a cytochrome as acceptor

EC 1.12.5 With a quinone or similar compound as acceptor

EC 1.12.7 With an iron–sulfur protein as acceptor

EC 1.12.98 With other known acceptors

EC 1.12.99 With unknown physiological acceptors

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

EC 1.13.11 With incorporation of two atoms of oxygen

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

EC 1.13.99 Miscellaneous

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

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

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

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

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

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

EC 1.14.13 With NADH or NADPH as one donor, and incorporation of one atom of oxygen into the other donor

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

EC 1.14.15 With reduced iron–sulfur protein as one donor, and incorporation of one atom of oxygen

EC 1.14.16 With reduced pteridine as one donor, and incorporation of one atom of oxygen into the other donor

EC 1.14.17 With reduced ascorbate as one donor, and incorporation of one atom of oxygen into the other donor

EC 1.14.18 With another compound as one donor, and incorporation of one atom of oxygen into the other donor

EC 1.14.19 With oxidation of a pair of donors resulting in the reduction of O2 to two molecules of water

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

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

EC 1.14.99 Miscellaneous

EC 1.15 Acting on superoxide as acceptor

EC 1.15.1

EC 1.16 Oxidizing metal ions

EC 1.16.1 With NAD+ or NADP+ as acceptor

EC 1.16.3 With oxygen as acceptor

EC 1.16.5 With a quinone or similar compound as acceptor

EC 1.16.8 With a flavin as acceptor

EC 1.16.9 With a copper protein as acceptor

EC 1.16.98 With other, known, physiological acceptors

EC 1.16.99 With unknown physiological acceptors

EC 1.17 Acting on CH or CH2 groups

EC 1.17.1 With NAD or NADP as acceptor

EC 1.17.2 With a cytochrome as acceptor

EC 1.17.3 With oxygen as acceptor

EC 1.17.4 With a disulfide as acceptor

EC 1.17.5 With a quinone or similar compound as acceptor

EC 1.17.7 With an iron–sulfur protein as acceptor

EC 1.17.98 With other, known, physiological acceptors

EC 1.17.99 With unknown physiological acceptors

EC 1.18 Acting on iron–sulfur proteins as donors

EC 1.18.1 With NAD+ or NADP+ as acceptor

EC 1.18.2 With dinitrogen as acceptor (deleted sub-subclass)

EC 1.18.3 With H+ as acceptor (deleted sub-subclass)

EC 1.18.6 With dinitrogen as acceptor

EC 1.18.96 With other, known, acceptors (deleted sub-subclass)

EC 1.18.99 With H+ as acceptor (deleted sub-subclass)

EC 1.19 Acting on reduced flavodoxin as donor

EC 1.19.1 With NAD+ or NADP+ as acceptor

EC 1.19.6 With dinitrogen as acceptor

EC 1.20 Acting on phosphorus or arsenic in donors

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

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

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

EC 1.20.9 With a copper protein as acceptor

EC 1.20.98 With other, known acceptors

EC 1.20.99 With unknown physiological acceptors

EC 1.21 Catalysing the reaction X-H + Y-H = X-Y

EC 1.21.3 With oxygen as acceptor

EC 1.21.4 With a disulfide as acceptor

EC 1.21.98 With other, known, physiological acceptors

EC 1.21.99 With unknown physiological acceptors

EC 1.22 Acting on halogen in donors

EC 1.22.1 With NAD+ or NADP+ as acceptor

EC 1.23 Reducing C-O-C group as acceptor

EC 1.23.1 With NADH or NADPH as donor

EC 1.97 Other oxidoreductases

EC 1.97.1 Sole sub-subclass for oxidoreductases that do not belong in the other subclasses

EC 1.98 Enzymes using H2 as reductant (deleted subclass)

EC 1.98.1.1: Now, ferredoxin hydrogenase

EC 1.99 Other enzymes using O2 as oxidant

EC 1.99.1 Hydroxylases (now covered by EC 1.14)

EC 1.99.2 Oxygenases (now covered by EC 1.13)