MetaBioME-Enzyme Info

CUEs Classification

Category	Applications
Agriculture	Synthesis of agrochemicals, genetic engineering in plants, bio-degradation of agrochemicals
Biosensor	Biosensors, enzyme assays, enzyme estimation analysis, diagnostics
Biotechnology	Biotechnology, synthesis of chemicals using microbial biocatalysts, industrial application of biocatalysts, bioreactor, molecular biology
Energy	Bio-fuel production, Bio-fuel cell, energy
Environment	Biodegradation of toxic compounds, treatment of industrial wastes and effluents, purification, detoxification
Food & Nutrition	Packaged foods and processing, juices, dairy, synthesis, bakery, brewing, biosensors, fermentation, animal feeds, agri-food
Medical	Diagnostics, pharmaceuticals, drug development, medicine, pharmacology, kits, cosmetics, supporting fine-chemicals
Other industries	Textile, leather, steel, paper, rubber, fiber, detergents
Miscellaneous	Enzymes with miscellaneous industrial applications

Enzyme Nomenclature

The International Union of Biochemistry and Molecular Biology have developed a nomenclature for enzymes, the EC numbers. Each enzyme is described by a sequence of four numbers preceded by "EC". The first number broadly classifies the enzyme based on its mechanism:

The ExplorEnz and ENZYME databases are the repositories of information relative to the nomenclature of enzymes and provide the latest version of enzyme nomenclature along with other functional information.

References

Bairoch, A. (2000) The ENZYME database in 2000. Nucleic Acids Res., 28, 304-305.
McDonald AG, Boyce S, Tipton KF (2009) ExplorEnz: the primary source of the IUBMB enzyme list. Nucleic Acids Res., Jan;37(Database issue):D593-7. Epub 2008 Sep 6.

The main level of classification is provided below:

EC 1 Oxidoreductases: catalyze oxidation/reduction reactions

EC 2 Transferases: transfer a functional group (e.g. a methyl or phosphate group)

EC 3 Hydrolases: catalyze the hydrolysis of various bonds

EC 4 Lyases: cleave various bonds by means other than hydrolysis and oxidation

EC 5 Isomerases: catalyze isomerization changes within a single molecule

EC 6 Ligases: join two molecules with covalent bonds

The complete nomenclature is available at http://www.chem.qmul.ac.uk/iubmb/enzyme/.

The detailed classification of Enzymes as per the ‘ENZYME nomenclature database’, Swiss Institute of Bioinformatics (SIB); Geneva, Switzerland, is provided below:

(Updated on: June 19,2007)

1. -. -.- Oxidoreductases.

1. 1. -.- Acting on the CH-OH group of donors.

1. 1. 1.- With NAD(+) or NADP(+) as acceptor.

1. 1. 2.- With a cytochrome as acceptor.

1. 1. 3.- With oxygen as acceptor.

1. 1. 4.- With a disulfide as acceptor.

1. 1. 5.- With a quinone or similar compound as acceptor.

1. 1.99.- With other acceptors.

1. 2. -.- Acting on the aldehyde or oxo group of donors.

1. 2. 1.- With NAD(+) or NADP(+) as acceptor.

1. 2. 2.- With a cytochrome as acceptor.

1. 2. 3.- With oxygen as acceptor.

1. 2. 4.- With a disulfide as acceptor.

1. 2. 7.- With an iron-sulfur protein as acceptor.

1. 2.99.- With other acceptors.

1. 3. -.- Acting on the CH-CH group of donors.

1. 3. 1.- With NAD(+) or NADP(+) as acceptor.

1. 3. 2.- With a cytochrome as acceptor.

1. 3. 3.- With oxygen as acceptor.

1. 3. 5.- With a quinone or related compound as acceptor.

1. 3. 7.- With an iron-sulfur protein as acceptor.

1. 3.99.- With other acceptors.

1. 4. -.- Acting on the CH-NH(2) group of donors.

1. 4. 1.- With NAD(+) or NADP(+) as acceptor.

1. 4. 2.- With a cytochrome as acceptor.

1. 4. 3.- With oxygen as acceptor.

1. 4. 4.- With a disulfide as acceptor.

1. 4. 7.- With an iron-sulfur protein as acceptor.

1. 4.99.- With other acceptors.

1. 5. -.- Acting on the CH-NH group of donors.

1. 5. 1.- With NAD(+) or NADP(+) as acceptor.

1. 5. 3.- With oxygen as acceptor.

1. 5. 4.- With a disulfide as acceptor.

1. 5. 5.- With a quinone or similar compound as acceptor.

1. 5. 7.- With an iron-sulfur protein as acceptor.

1. 5. 8.- With a flavin as acceptor.

1. 5.99.- With other acceptors.

1. 6. -.- Acting on NADH or NADPH.

1. 6. 1.- With NAD(+) or NADP(+) as acceptor.

1. 6. 2.- With a heme protein as acceptor.

1. 6. 3.- With a oxygen as acceptor.

1. 6. 5.- With a quinone or similar compound as acceptor.

1. 6. 6.- With a nitrogenous group as acceptor.

1. 6.99.- With other acceptors.

1. 7. -.- Acting on other nitrogenous compounds as donors.

1. 7. 1.- With NAD(+) or NADP(+) as acceptor.

1. 7. 2.- With a cytochrome as acceptor.

1. 7. 3.- With oxygen as acceptor.

1. 7. 7.- With an iron-sulfur protein as acceptor.

1. 7.99.- With other acceptors.

1. 8. -.- Acting on a sulfur group of donors.

1. 8. 1.- With NAD(+) or NADP(+) as acceptor.

1. 8. 2.- With a cytochrome as acceptor.

1. 8. 3.- With oxygen as acceptor.

1. 8. 4.- With a disulfide as acceptor.

1. 8. 5.- With a quinone or similar compound as acceptor.

1. 8. 7.- With an iron-sulfur protein as acceptor.

1. 8.98.- With other, known, acceptors.

1. 8.99.- With other acceptors.

1. 9. -.- Acting on a heme group of donors.

1. 9. 3.- With oxygen as acceptor.

1. 9. 6.- With a nitrogenous group as acceptor.

1. 9.99.- With other acceptors.

1.10. -.- Acting on diphenols and related substances as donors.

1.10. 1.- With NAD(+) or NADP(+) as acceptor.

1.10. 2.- With a cytochrome as acceptor.

1.10. 3.- With oxygen as acceptor.

1.10.99.- With other acceptors.

1.11. -.- Acting on a peroxide as acceptor.

1.11. 1.- Peroxidases.

1.12. -.- Acting on hydrogen as donor.

1.12. 1.- With NAD(+) or NADP(+) as acceptor.

1.12. 2.- With a cytochrome as acceptor.

1.12. 5.- With a quinone or similar compound as acceptor.

1.12. 7.- With an iron-sulfur protein as acceptor.

1.12.98.- With other known acceptors.

1.12.99.- With other acceptors.

1.13. -.- Acting on single donors with incorporation of molecular oxygen.

1.13.11.- With incorporation of two atoms of oxygen.

1.13.12.- With incorporation of one atom of oxygen.

1.13.99.- Miscellaneous (requires further characterization).

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

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

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

1.14.13.- With NADH or NADPH as one donor, and incorporation of one atom of oxygen.

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

1.14.15.- With a reduced iron-sulfur protein as one donor, and incorporation of one atom of oxygen.

1.14.16.- With reduced pteridine as one donor, and incorporation of one atom of oxygen.

1.14.17.- With reduced ascorbate as one donor, and incorporation of one atom of oxygen.

1.14.18.- With another compound as one donor, and incorporation of one atom of oxygen.

1.14.19.- With oxidation of a pair of donors resulting in the reduction of molecular oxygen to two molecules of water.

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

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

1.14.99.- Miscellaneous (requires further characterization).

1.15. -.- Acting on superoxide as acceptor.

1.15. 1.- Acting on superoxide as acceptor.

1.16. -.- Oxidizing metal ions.

1.16. 1.- With NAD(+) or NADP(+) as acceptor.

1.16. 3.- With oxygen as acceptor.

1.16. 8.- With flavin as acceptor.

1.17. -.- Acting on CH or CH(2) groups.

1.17. 1.- With NAD(+) or NADP(+) as acceptor.

1.17. 3.- With oxygen as acceptor.

1.17. 4.- With a disulfide as acceptor.

1.17. 5.- With a quinone or similar compound as acceptor.

1.17.99.- With other acceptors.

1.18. -.- Acting on iron-sulfur proteins as donors.

1.18. 1.- With NAD(+) or NADP(+) as acceptor.

1.18. 6.- With dinitrogen as acceptor.

1.19. -.- Acting on reduced flavodoxin as donor.

1.19. 6.- With dinitrogen as acceptor.

1.20. -.- Acting on phosphorus or arsenic in donors.

1.20. 1.- Acting on phosphorus or arsenic in donors, with NAD(P)(+) as acceptor.

1.20. 4.- Acting on phosphorus or arsenic in donors, with disulfide as acceptor.

1.20.98.- Acting on phosphorus or arsenic in donors, with other, known acceptors.

1.20.99.- Acting on phosphorus or arsenic in donors, with other acceptors.

1.21. -.- Acting on x-H and y-H to form an x-y bond.

1.21. 3.- With oxygen as acceptor.

1.21. 4.- With a disulfide as acceptor.

1.21.99.- With other acceptors.

1.97. -.- Other oxidoreductases.

1.97. 1.- Sole sub-subclass for oxidoreductases that do not belong in the other subclasses.

2. -. -.- Transferases.

2. 1. -.- Transferring one-carbon groups.

2. 1. 1.- Methyltransferases.

2. 1. 2.- Hydroxymethyl-, formyl- and related transferases.

2. 1. 3.- Carboxyl- and carbamoyltransferases.

2. 1. 4.- Amidinotransferases.

2. 2. -.- Transferring aldehyde or ketone residues.

2. 2. 1.- Transketolases and transaldolases.

2. 3. -.- Acyltransferases.

2. 3. 1.- Transferring groups other than amino-acyl groups.

2. 3. 2.- Aminoacyltransferases.

2. 3. 3.- Acyl groups converted into alkyl on transfer.

2. 4. -.- Glycosyltransferases.

2. 4. 1.- Hexosyltransferases.

2. 4. 2.- Pentosyltransferases.

2. 4.99.- Transferring other glycosyl groups.

2. 5. -.- Transferring alkyl or aryl groups, other than methyl groups.

2. 5. 1.- Transferring alkyl or aryl groups, other than methyl groups.

2. 6. -.- Transferring nitrogenous groups.

2. 6. 1.- Transaminases (aminotransferases).

2. 6. 3.- Oximinotransferases.

2. 6.99.- Transferring other nitrogenous groups.

2. 7. -.- Transferring phosphorous-containing groups.

2. 7. 1.- Phosphotransferases with an alcohol group as acceptor.

2. 7. 2.- Phosphotransferases with a carboxyl group as acceptor.

2. 7. 3.- Phosphotransferases with a nitrogenous group as acceptor.

2. 7. 4.- Phosphotransferases with a phosphate group as acceptor.

2. 7. 6.- Diphosphotransferases.

2. 7. 7.- Nucleotidyltransferases.

2. 7. 8.- Transferases for other substituted phosphate groups.

2. 7. 9.- Phosphotransferases with paired acceptors.

2. 7.10.- Protein-tyrosine kinases.

2. 7.11.- Protein-serine/threonine kinases.

2. 7.12.- Dual-specificity kinases (those acting on Ser/Thr and Tyr residues).

2. 7.13.- Protein-histidine kinases.

2. 7.99.- Other protein kinases.

2. 8. -.- Transferring sulfur-containing groups.

2. 8. 1.- Sulfurtransferases.

2. 8. 2.- Sulfotransferases.

2. 8. 3.- CoA-transferases.

2. 8. 4.- Transferring alkylthio groups.

2. 9. -.- Transferring selenium-containing groups.

2. 9. 1.- Selenotransferases.

3. -. -.- Hydrolases.

3. 1. -.- Acting on ester bonds.

3. 1. 1.- Carboxylic ester hydrolases.

3. 1. 2.- Thiolester hydrolases.

3. 1. 3.- Phosphoric monoester hydrolases.

3. 1. 4.- Phosphoric diester hydrolases.

3. 1. 5.- Triphosphoric monoester hydrolases.

3. 1. 6.- Sulfuric ester hydrolases.

3. 1. 7.- Diphosphoric monoester hydrolases.

3. 1. 8.- Phosphoric triester hydrolases.

3. 1.11.- Exodeoxyribonucleases producing 5'-phosphomonoesters.

3. 1.13.- Exoribonucleases producing 5'-phosphomonoesters.

3. 1.14.- Exoribonucleases producing 3'-phosphomonoesters.

3. 1.15.- Exonucleases active with either ribo- or deoxyribonucleic acid and producing 5'-phosphomonoesters.

3. 1.16.- Exonucleases active with either ribo- or deoxyribonucleic acid and producing 3'-phosphomonoesters.

3. 1.21.- Endodeoxyribonucleases producing 5'-phosphomonoesters.

3. 1.22.- Endodeoxyribonucleases producing other than 5'-phosphomonoesters.

3. 1.25.- Site-specific endodeoxyribonucleases specific for altered bases.

3. 1.26.- Endoribonucleases producing 5'-phosphomonoesters.

3. 1.27.- Endoribonucleases producing other than 5'-phosphomonoesters.

3. 1.30.- Endoribonucleases active with either ribo- or deoxyribonucleic acid and producing 5'-phosphomonoesters.

3. 1.31.- Endoribonucleases active with either ribo- or deoxyribonucleic acid and producing 3'-phosphomonoesters.

3. 2. -.- Glycosylases.

3. 2. 1.- Glycosidases, i.e. enzymes hydrolyzing O- and S-glycosyl compounds.

3. 2. 2.- Hydrolyzing N-glycosyl compounds.

3. 3. -.- Acting on ether bonds.

3. 3. 1.- Thioether and trialkylsulfonium hydrolases.

3. 3. 2.- Ether hydrolases.

3. 4. -.- Acting on peptide bonds (peptide hydrolases).

3. 4.11.- Aminopeptidases.

3. 4.13.- Dipeptidases.

3. 4.14.- Dipeptidyl-peptidases and tripeptidyl-peptidases.

3. 4.15.- Peptidyl-dipeptidases.

3. 4.16.- Serine-type carboxypeptidases.

3. 4.17.- Metallocarboxypeptidases.

3. 4.18.- Cysteine-type carboxypeptidases.

3. 4.19.- Omega peptidases.

3. 4.21.- Serine endopeptidases.

3. 4.22.- Cysteine endopeptidases.

3. 4.23.- Aspartic endopeptidases.

3. 4.24.- Metalloendopeptidases.

3. 4.25.- Threonine endopeptidases.

3. 4.99.- Endopeptidases of unknown catalytic mechanism.

3. 5. -.- Acting on carbon-nitrogen bonds, other than peptide bonds.

3. 5. 1.- In linear amides.

3. 5. 2.- In cyclic amides.

3. 5. 3.- In linear amidines.

3. 5. 4.- In cyclic amidines.

3. 5. 5.- In nitriles.

3. 5.99.- In other compounds.

3. 6. -.- Acting on acid anhydrides.

3. 6. 1.- In phosphorous-containing anhydrides.

3. 6. 2.- In sulfonyl-containing anhydrides.

3. 6. 3.- Acting on acid anhydrides; catalyzing transmembrane movement of substances.

3. 6. 4.- Acting on acid anhydrides; involved in cellular and subcellular movement.

3. 6. 5.- Acting on GTP; involved in cellular and subcellular movement.

3. 7. -.- Acting on carbon-carbon bonds.

3. 7. 1.- In ketonic substances.

3. 8. -.- Acting on halide bonds.

3. 8. 1.- In C-halide compounds.

3. 9. -.- Acting on phosphorus-nitrogen bonds.

3. 9. 1.- Acting on phosphorus-nitrogen bonds.

3.10. -.- Acting on sulfur-nitrogen bonds.

3.10. 1.- Acting on sulfur-nitrogen bonds.

3.11. -.- Acting on carbon-phosphorus bonds.

3.11. 1.- Acting on carbon-phosphorus bonds.

3.12. -.- Acting on sulfur-sulfur bonds.

3.12. 1.- Acting on sulfur-sulfur bonds.

3.13. -.- Acting on carbon-sulfur bonds.

3.13. 1.- Acting on carbon-sulfur bonds.

4. -. -.- Lyases.

4. 1. -.- Carbon-carbon lyases.

4. 1. 1.- Carboxy-lyases.

4. 1. 2.- Aldehyde-lyases.

4. 1. 3.- Oxo-acid-lyases.

4. 1.99.- Other carbon-carbon lyases.

4. 2. -.- Carbon-oxygen lyases.

4. 2. 1.- Hydro-lyases.

4. 2. 2.- Acting on polysaccharides.

4. 2. 3.- Acting on phosphates.

4. 2.99.- Other carbon-oxygen lyases.

4. 3. -.- Carbon-nitrogen lyases.

4. 3. 1.- Ammonia-lyases.

4. 3. 2.- Lyases acting on amides, amidines, etc.

4. 3. 3.- Amine-lyases.

4. 4. -.- Carbon-sulfur lyases.

4. 4. 1.- Carbon-sulfur lyases.

4. 5. -.- Carbon-halide lyases.

4. 5. 1.- Carbon-halide lyases.

4. 6. -.- Phosphorus-oxygen lyases.

4. 6. 1.- Phosphorus-oxygen lyases.

4.99. -.- Other lyases.

4.99. 1.- Sole sub-subclass for lyases that do not belong in the other subclasses.

5. -. -.- Isomerases.

5. 1. -.- Racemases and epimerases.

5. 1. 1.- Acting on amino acids and derivatives.

5. 1. 2.- Acting on hydroxy acids and derivatives.

5. 1. 3.- Acting on carbohydrates and derivatives.

5. 1.99.- Acting on other compounds.

5. 2. -.- Cis-trans-isomerases.

5. 2. 1.- Cis-trans Isomerases.

5. 3. -.- Intramolecular oxidoreductases.

5. 3. 1.- Interconverting aldoses and ketoses.

5. 3. 2.- Interconverting keto- and enol- groups.

5. 3. 3.- Transposing C==C bonds.

5. 3. 4.- Transposing S-S bonds.

5. 3.99.- Other intramolecular oxidoreductases.

5. 4. -.- Intramolecular transferases (mutases).

5. 4. 1.- Transferring acyl groups.

5. 4. 2.- Phosphotransferases (phosphomutases).

5. 4. 3.- Transferring amino groups.

5. 4. 4.- Transferring hydroxy groups.

5. 4.99.- Transferring other groups.

5. 5. -.- Intramolecular lyases.

5. 5. 1.- Intramolecular lyases.

5.99. -.- Other isomerases.

5.99. 1.- Sole sub-subclass for isomerases that do not belong in the other subclasses.

6. -. -.- Ligases.

6. 1. -.- Forming carbon-oxygen bonds.

6. 1. 1.- Ligases forming aminoacyl-tRNA and related compounds.

6. 2. -.- Forming carbon-sulfur bonds.

6. 2. 1.- Acid--thiol ligases.

6. 3. -.- Forming carbon-nitrogen bonds.

6. 3. 1.- Acid--ammonia (or amide) ligases (amide synthases).

6. 3. 2.- Acid--D-amino-acid ligases (peptide synthases).

6. 3. 3.- Cyclo-ligases.

6. 3. 4.- Other carbon--nitrogen ligases.

6. 3. 5.- Carbon--nitrogen ligases with glutamine as amido-N-donor.

6. 4. -.- Forming carbon-carbon bonds.

6. 4. 1.- Ligases that form carbon-carbon bonds.

6. 5. -.- Forming phosphoric ester bonds.

6. 5. 1.- Ligases that form phosphoric-ester bonds.

6. 6. -.- Forming nitrogen-metal bonds.

6. 6. 1.- Forming coordination complexes.