Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (NC-IUBMB)

Enzyme Nomenclature. Recommendations

Contents EC 5.1.1.1 - EC 5.99.1.3

EC 5. Isomerases

EC 5.1 Racemases and Epimerases

EC 5.1.1 Acting on Amino Acids and Derivatives

EC 5.1.1.1 alanine racemase
EC 5.1.1.2 methionine racemase
EC 5.1.1.3 glutamate racemase
EC 5.1.1.4 proline racemase
EC 5.1.1.5 lysine racemase
EC 5.1.1.6 threonine racemase
EC 5.1.1.7 diaminopimelate epimerase
EC 5.1.1.8 4-hydroxyproline epimerase
EC 5.1.1.9 arginine racemase
EC 5.1.1.10 amino-acid racemase
EC 5.1.1.11 phenylalanine racemase (ATP-hydrolysing)
EC 5.1.1.12 ornithine racemase
EC 5.1.1.13 aspartate racemase
EC 5.1.1.14 nocardicin-A epimerase
EC 5.1.1.15 2-aminohexano-6-lactam racemase
EC 5.1.1.16 protein-serine epimerase
EC 5.1.1.17 isopenicillin-N epimerase
EC 5.1.1.18 serine racemase
EC 5.1.1.19 O-ureido-serine racemase
EC 5.1.1.20 L-Ala-D/L-Glu epimerase
EC 5.1.1.21 isoleucine 2-epimerase
EC 5.1.1.22 4-hydroxyproline betaine 2-epimerase

EC 5.1.2 Acting on Hydroxy Acids and Derivatives

EC 5.1.2.1 lactate racemase
EC 5.1.2.2 mandelate racemase
EC 5.1.2.3 3-hydroxybutyryl-CoA epimerase
EC 5.1.2.4 acetoin racemase
EC 5.1.2.5 tartrate epimerase
EC 5.1.2.6 isocitrate epimerase
EC 5.1.2.7 tagaturonate epimerase

EC 5.1.3 Acting on Carbohydrates and Derivatives

EC 5.1.3.1 ribulose-phosphate 3-epimerase
EC 5.1.3.2 UDP-glucose 4-epimerase
EC 5.1.3.3 aldose 1-epimerase
EC 5.1.3.4 L-ribulose-5-phosphate 4-epimerase
EC 5.1.3.5 UDP-arabinose 4-epimerase
EC 5.1.3.6 UDP-glucuronate 4-epimerase
EC 5.1.3.7 UDP-N-acetylglucosamine 4-epimerase
EC 5.1.3.8 N-acylglucosamine 2-epimerase
EC 5.1.3.9 N-acylglucosamine-6-phosphate 2-epimerase
EC 5.1.3.10 CDP-paratose 2-epimerase
EC 5.1.3.11 cellobiose epimerase
EC 5.1.3.12 UDP-glucuronate 5'-epimerase
EC 5.1.3.13 dTDP-4-dehydrorhamnose 3,5-epimerase
EC 5.1.3.14 UDP-N-acetylglucosamine 2-epimerase (non-hydrolysing)
EC 5.1.3.15 glucose-6-phosphate 1-epimerase
EC 5.1.3.16 UDP-glucosamine 4-epimerase
EC 5.1.3.17 heparosan-N-sulfate-glucuronate 5-epimerase
EC 5.1.3.18 GDP-mannose 3,5-epimerase
EC 5.1.3.19 chondroitin-glucuronate 5-epimerase
EC 5.1.3.20 ADP-glyceromanno-heptose 6-epimerase
EC 5.1.3.21 maltose epimerase
EC 5.1.3.22 L-ribulose-5-phosphate 3-epimerase
EC 5.1.3.23 UDP-2,3-diacetamido-2,3-dideoxyglucuronic acid 2-epimerase
EC 5.1.3.24 N-acetylneuraminate epimerase
EC 5.1.3.25 dTDP-L-rhamnose 4-epimerase
EC 5.1.3.26 N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol 4-epimerase
EC 5.1.3.27 dTDP-4-dehydro-6-deoxy-D-glucose 3-epimerase
EC 5.1.3.28 UDP-N-acetyl-L-fucosamine synthase
EC 5.1.3.29 L-fucose mutarotase
EC 5.1.3.30 D-psicose 3-epimerase
EC 5.1.3.31 D-tagatose 3-epimerase
EC 5.1.3.32 L-rhamnose mutarotase
EC 5.1.3.33 2-epi-5-epi-valiolone epimerase
EC 5.1.3.34 monoglucosyldiacylglycerol epimerase
EC 5.1.3.35 2-epi-5-epi-valiolone 7-phosphate 2-epimerase
EC 5.1.3.36 heparosan-glucuronate 5-epimerase
EC 5.1.3.37 mannuronan 5-epimerase
EC 5.1.3.38 D-erythrulose 1-phosphate 3-epimerase
EC 5.1.3.39 L-erythrulose 4-phosphate epimerase
EC 5.1.3.40 D-tagatose 6-phosphate 4-epimerase

EC 5.1.99 Acting on Other Compounds

EC 5.1.99.1 methylmalonyl-CoA epimerase
EC 5.1.99.2 16-hydroxysteroid epimerase
EC 5.1.99.3 allantoin racemase
EC 5.1.99.4 α-methylacyl-CoA racemase
EC 5.1.99.5 hydantoin racemase
EC 5.1.99.6 NAD(P)H-hydrate epimerase
EC 5.1.99.7 dihydroneopterin triphosphate 2'-epimerase
EC 5.1.99.8 7,8-dihydroneopterin epimerase

EC 5.2 cis-trans-Isomerases

EC 5.2.1.1 maleate isomerase
EC 5.2.1.2 maleylacetoacetate isomerase
EC 5.2.1.3 deleted covered by EC 1.1.1.300, EC 2.3.1.135, EC 3.1.1.64, and EC 1.1.1.315
EC 5.2.1.4 maleylpyruvate isomerase
EC 5.2.1.5 linoleate isomerase
EC 5.2.1.6 furylfuramide isomerase
EC 5.2.1.7 transferred now EC 3.1.1.64
EC 5.2.1.8 peptidylprolyl isomerase
EC 5.2.1.9 farnesol 2-isomerase
EC 5.2.1.10 2-chloro-4-carboxymethylenebut-2-en-1,4-olide isomerase
EC 5.2.1.11 deleted entry
EC 5.2.1.12 ζ-carotene isomerase
EC 5.2.1.13 prolycopene isomerase
EC 5.2.1.14 β-carotene isomerase

EC 5.3 Intramolecular Oxidoreductases

EC 5.3.1 Interconverting Aldoses and Ketoses

EC 5.3.1.1 triose-phosphate isomerase
EC 5.3.1.2 deleted
EC 5.3.1.3 D-arabinose isomerase
EC 5.3.1.4 L-arabinose isomerase
EC 5.3.1.5 xylose isomerase
EC 5.3.1.6 ribose-5-phosphate isomerase
EC 5.3.1.7 mannose isomerase
EC 5.3.1.8 mannose-6-phosphate isomerase
EC 5.3.1.9 glucose-6-phosphate isomerase
EC 5.3.1.10 now EC 3.5.99.6
EC 5.3.1.11 deleted
EC 5.3.1.12 glucuronate isomerase
EC 5.3.1.13 arabinose-5-phosphate isomerase
EC 5.3.1.14 L-rhamnose isomerase
EC 5.3.1.15 D-lyxose ketol-isomerase
EC 5.3.1.16 1-(5-phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino]imidazole-4-carboxamide isomerase
EC 5.3.1.17 4-deoxy-L-threo-5-hexosulose-uronate ketol-isomerase
EC 5.3.1.18 deleted
EC 5.3.1.19 now EC 2.6.1.16
EC 5.3.1.20 ribose isomerase
EC 5.3.1.21 corticosteroid side-chain-isomerase
EC 5.3.1.22 hydroxypyruvate isomerase
EC 5.3.1.23 5-methylthioribose-1-phosphate isomerase
EC 5.3.1.24 phosphoribosylanthranilate isomerase
EC 5.3.1.25 L-fucose isomerase
EC 5.3.1.26 galactose-6-phosphate isomerase
EC 5.3.1.27 6-phospho-3-hexuloisomerase
EC 5.3.1.28 D-sedoheptulose 7-phosphate isomerase
EC 5.3.1.29 ribose 1,5-bisphosphate isomerase
EC 5.3.1.30 5-deoxy-glucuronate isomerase
EC 5.3.1.31 sulfoquinovose isomerase
EC 5.3.1.32 (4S)-4-hydroxy-5-phosphooxypentane-2,3-dione isomerase
EC 5.3.1.33 L-erythrulose 1-phosphate isomerase
EC 5.3.1.34 D-erythrulose 4-phosphate isomerase

EC 5.3.2 Interconverting Keto- and Enol-Groups

EC 5.3.2.1 phenylpyruvate tautomerase
EC 5.3.2.2 oxaloacetate tautomerase
EC 5.3.2.3 TDP-4-oxo-6-deoxy-α-D-glucose-3,4-oxoisomerase (dTDP-3-dehydro-6-deoxy-α-D-galactopyranose-forming)
EC 5.3.2.4 TDP-4-oxo-6-deoxy-α-D-glucose-3,4-oxoisomerase (dTDP-3-dehydro-6-deoxy-α-D-glucopyranose-forming)
EC 5.3.2.5 2,3-diketo-5-methylthiopentyl-1-phosphate enolase
EC 5.3.2.6 2-hydroxymuconate tautomerase
EC 5.3.2.7 ascopyrone tautomerase
EC 5.3.2.8 4-oxalomesaconate tautomerase

EC 5.3.3 Transposing C=C Bonds

EC 5.3.3.1 steroid Δ-isomerase
EC 5.3.3.2 isopentenyl-diphosphate Δ-isomerase
EC 5.3.3.3 vinylacetyl-CoA Δ-isomerase
EC 5.3.3.4 muconolactone Δ-isomerase
EC 5.3.3.5 cholestenol Δ-isomerase
EC 5.3.3.6 methylitaconate Δ-isomerase
EC 5.3.3.7 aconitate Δ-isomerase
EC 5.3.3.8 dodecenoyl-CoA Δ-isomerase
EC 5.3.3.9 prostaglandin-A1 Δ-isomerase
EC 5.3.3.10 5-carboxymethyl-2-hydroxymuconate Δ-isomerase
EC 5.3.3.11 isopiperitenone Δ-isomerase
EC 5.3.3.12 L-dopachrome isomerase
EC 5.3.3.13 polyenoic fatty acid isomerase
EC 5.3.3.14 trans-2-decenoyl-[acyl-carrier protein] isomerase
EC 5.3.3.15 transferred now EC 5.3.2.7
EC 5.3.3.16 transferred now EC 5.3.2.8
EC 5.3.3.17 trans-2,3-dihydro-3-hydroxyanthranilate isomerase
EC 5.3.3.18 2-(1,2-epoxy-1,2-dihydrophenyl)acetyl-CoA isomerase
EC 5.3.3.19 3-[(4R)-4-hydroxycyclohexa-1,5-dien-1-yl]-2-oxopropanoate isomerase
EC 5.3.3.20 transferred now EC 5.4.99.64

EC 5.3.4 Transposing S-S Bonds

EC 5.3.4.1 protein disulfide-isomerase

EC 5.3.99 Other Intramolecular Oxidoreductases

EC 5.3.99.1 deleted
EC 5.3.99.2 prostaglandin-D synthase
EC 5.3.99.3 prostaglandin-E synthase
EC 5.3.99.4 prostaglandin-I synthase
EC 5.3.99.5 thromboxane-A synthase
EC 5.3.99.6 allene-oxide cyclase
EC 5.3.99.7 styrene-oxide isomerase
EC 5.3.99.8 capsanthin/capsorubin synthase
EC 5.3.99.9 neoxanthin synthase
EC 5.3.99.10 thiazole tautomerase
EC 5.3.99.11 2-keto-myo-inositol isomerase

EC 5.4 Intramolecular Transferases

EC 5.4.1 Transferring Acyl Groups

EC 5.4.1.1 lysolecithin acylmutase
EC 5.4.1.2 transferred now EC 5.4.99.61
EC 5.4.1.3 2-methylfumaryl-CoA isomerase
EC 5.4.1.4 D-galactarolactone isomerase

EC 5.4.2 Phosphotransferases (Phosphomutases)

EC 5.4.2.1 transferred now EC 5.4.2.11 and EC 5.4.2.12
EC 5.4.2.2 phosphoglucomutase (α-D-glucose-1,6-bisphosphate-dependent)
EC 5.4.2.3 phosphoacetylglucosamine mutase
EC 5.4.2.4 bisphosphoglycerate mutase
EC 5.4.2.5 phosphoglucomutase (glucose-cofactor)
EC 5.4.2.6 β-phosphoglucomutase
EC 5.4.2.7 phosphopentomutase
EC 5.4.2.8 phosphomannomutase
EC 5.4.2.9 phosphoenolpyruvate mutase
EC 5.4.2.10 phosphoglucosamine mutase
EC 5.4.2.11 phosphoglycerate mutase (2,3-diphosphoglycerate-dependent)
EC 5.4.2.12 phosphoglycerate mutase (2,3-diphosphoglycerate-independent)

EC 5.4.3 Transferring Amino Groups

EC 5.4.3.1 deleted
EC 5.4.3.2 lysine 2,3-aminomutase
EC 5.4.3.3 β-lysine 5,6-aminomutase
EC 5.4.3.4 D-lysine 5,6-aminomutase
EC 5.4.3.5 D-ornithine 4,5-aminomutase
EC 5.4.3.6 tyrosine 2,3-aminomutase
EC 5.4.3.7 leucine 2,3-aminomutase
EC 5.4.3.8 glutamate-1-semialdehyde 2,1-aminomutase
EC 5.4.3.9 glutamate 2,3-aminomutase
EC 5.4.3.10 phenylalanine aminomutase (L-β-phenylalanine forming)
EC 5.4.3.11 phenylalanine aminomutase (D-β-phenylalanine forming)

EC 5.4.4 Transferring hydroxy groups

EC 5.4.4.1 (hydroxyamino)benzene mutase
EC 5.4.4.2 isochorismate synthase
EC 5.4.4.3 3-(hydroxyamino)phenol mutase EC 5.4.4.4 geraniol isomerase
EC 5.4.4.5 9,12-octadecadienoate 8-hydroperoxide 8R-isomerase
EC 5.4.4.6 9,12-octadecadienoate 8-hydroperoxide 8S-isomerase
EC 5.4.4.7 hydroperoxy icosatetraenoate isomerase

EC 5.4.99 Transferring Other Groups

EC 5.4.99.1 methylaspartate mutase
EC 5.4.99.2 methylmalonyl-CoA mutase
EC 5.4.99.3 2-acetolactate mutase
EC 5.4.99.4 2-methyleneglutarate mutase
EC 5.4.99.5 chorismate mutase
EC 5.4.99.6 now EC 5.4.4.2
EC 5.4.99.7 lanosterol synthase
EC 5.4.99.8 cycloartenol synthase
EC 5.4.99.9 UDP-galactopyranose mutase
EC 5.4.99.10 deleted, included in EC 5.4.99.11
EC 5.4.99.11 isomaltulose synthase
EC 5.4.99.12 tRNA pseudouridine38-40 synthase
EC 5.4.99.13 isobutyryl-CoA mutase
EC 5.4.99.14 4-carboxymethyl-4-methylbutenolide mutase
EC 5.4.99.15 (1→4)-α-D-glucan 1-α-D-glucosylmutase
EC 5.4.99.16 maltose α-D-glucosyltransferase
EC 5.4.99.17 squalene—hopene cyclase
EC 5.4.99.18 5-(carboxyamino)imidazole ribonucleotide mutase
EC 5.4.99.19 16S rRNA pseudouridine516 synthase
EC 5.4.99.20 23S rRNA pseudouridine2457 synthase
EC 5.4.99.21 23S rRNA pseudouridine2604 synthase
EC 5.4.99.22 23S rRNA pseudouridine2605 synthase
EC 5.4.99.23 23S rRNA pseudouridine1911/1915/1917 synthase
EC 5.4.99.24 23S rRNA pseudouridine955/2504/2580 synthase
EC 5.4.99.25 tRNA pseudouridine55 synthase
EC 5.4.99.26 tRNA pseudouridine65 synthase
EC 5.4.99.27 tRNA pseudouridine13 synthase
EC 5.4.99.28 tRNA pseudouridine32 synthase
EC 5.4.99.29 23S rRNA pseudouridine746 synthase
EC 5.4.99.30 UDP-arabinopyranose mutase
EC 5.4.99.31 thalianol synthase
EC 5.4.99.32 protostadienol synthase
EC 5.4.99.33 cucurbitadienol synthase
EC 5.4.99.34 germanicol synthase
EC 5.4.99.35 taraxerol synthase
EC 5.4.99.36 isomultiflorenol synthase
EC 5.4.99.37 dammaradiene synthase
EC 5.4.99.38 camelliol C synthase
EC 5.4.99.39 β-amyrin synthase
EC 5.4.99.40 α-amyrin synthase
EC 5.4.99.41 lupeol synthase
EC 5.4.99.42 tRNA pseudouridine31 synthase
EC 5.4.99.43 21S rRNA pseudouridine2819 synthase
EC 5.4.99.44 mitochondrial tRNA pseudouridine27/28 synthase
EC 5.4.99.45 tRNA pseudouridine38/39 synthase
EC 5.4.99.46 shionone synthase
EC 5.4.99.47 parkeol synthase
EC 5.4.99.48 achilleol B synthase
EC 5.4.99.49 glutinol synthase
EC 5.4.99.50 friedelin synthase
EC 5.4.99.51 baccharis oxide synthase
EC 5.4.99.52 α-seco-amyrin synthase
EC 5.4.99.53 marneral synthase
EC 5.4.99.54 β-seco-amyrin synthase
EC 5.4.99.55 δ-amyrin synthase
EC 5.4.99.56 tirucalladienol synthase
EC 5.4.99.57 baruol synthase
EC 5.4.99.58 methylornithine synthase
EC 5.4.99.59 dTDP-fucopyranose mutase
EC 5.4.99.60 cobalt-precorrin-8 methylmutase
EC 5.4.99.61 precorrin-8X methylmutase
EC 5.4.99.62 D-ribose pyranase
EC 5.4.99.63 ethylmalonyl-CoA mutase
EC 5.4.99.64 2-hydroxyisobutanoyl-CoA mutase

EC 5.5 Intramolecular Lyases

EC 5.5.1.1 muconate cycloisomerase
EC 5.5.1.2 3-carboxy-cis,cis-muconate cycloisomerase
EC 5.5.1.3 tetrahydroxypteridine cycloisomerase
EC 5.5.1.4 inositol-3-phosphate synthase
EC 5.5.1.5 carboxy-cis,cis-muconate cyclase
EC 5.5.1.6 chalcone isomerase
EC 5.5.1.7 chloromuconate cycloisomerase
EC 5.5.1.8 (+)-bornyl diphosphate synthase
EC 5.5.1.9 cycloeucalenol cycloisomerase
EC 5.5.1.10 α-pinene-oxide decyclase
EC 5.5.1.11 dichloromuconate cycloisomerase
EC 5.5.1.12 copalyl diphosphate synthase
EC 5.5.1.13 ent-copalyl diphosphate synthase
EC 5.5.1.14 syn-copalyl diphosphate synthase
EC 5.5.1.15 terpentedienyl-diphosphate synthase
EC 5.5.1.16 halimadienyl-diphosphate synthase
EC 5.5.1.17 (S)-β-macrocarpene synthase
EC 5.5.1.18 lycopene ε-cyclase
EC 5.5.1.19 lycopene β-cyclase
EC 5.5.1.20 prosolanapyrone-III cycloisomerase
EC 5.5.1.21 deleted
EC 5.5.1.22 (–)-bornyl diphosphate synthase
EC 5.5.1.23 aklanonic acid methyl ester cyclase
EC 5.5.1.24 tocopherol cyclase
EC 5.5.1.25 3,6-anhydro-L-galactonate cycloisomerase
EC 5.5.1.26 nogalonic acid methyl ester cyclase
EC 5.5.1.27 D-galactarolactone cycloisomerase

EC 5.99 Other Isomerases

EC 5.99.1.1 thiocyanate isomerase
EC 5.99.1.2 DNA topoisomerase
EC 5.99.1.3 DNA topoisomerase (ATP-hydrolysing)
EC 5.99.1.4 2-hydroxychromene-2-carboxylate isomerase


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