An asterisk before 'EC' indicates that this is an amendment to an existing enzyme rather than a new enzyme entry.

Common name: codeinone reductase (NADPH)

Reaction: codeine + NADP⁺ = codeinone + NADPH + H⁺

For diagram click here.

Systematic name: codeine:NADP⁺ oxidoreductase

Comments: Catalyses the reversible reduction of codeinone to codeine, which is a direct precursor of morphine in the opium poppy plant, Papaver somniferum.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 153302-41-1

References:

1. Lenz, R. and Zenk, M.H. Stereoselective reduction of codeinone, the penultimate step during morphine biosynthesis in Papaver somniferum. Tetrahedron Lett. 36 (1995) 2449-2452.

2. Lenz, R. and Zenk, M.H. Purification and properties of codeinone reductase (NADPH) from Papaver somniferum cell cultures. Eur. J. Biochem. 233 (1995) 132-139. [PMID: 7588736]

*EC 1.1.1.248

Common name: salutaridine reductase (NADPH)

Reaction: salutaridinol + NADP⁺ = salutaridine + NADPH + H⁺

For diagram click here.

Systematic name: salutaridinol:NADP⁺ 7-oxidoreductase

Comments: Catalyses the reversible reduction of salutaridine to salutaridinol, which is a direct precursor of morphinan alkaloids in the poppy plant.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 152743-95-8

References:

1. Gerady, R. and Zenk, M.H. Purification and characterization of salutaridine:NADPH 7-oxidoreductase from Papaver somniferum. Phytochemistry 34 (1993) 125-132.

*EC 1.1.1.260

Common name: sulcatone reductase

Reaction: sulcatol + NAD⁺ = sulcatone + NADH + H⁺

Glossary entries:
sulcatone: 6-methylhept-5-en-2-one
sulcatol: 6-methylhept-5-en-2-ol

Systematic name: sulcatol:NAD⁺ oxidoreductase

Comments: Studies on the effects of growth-stage and nutrient supply on the stereochemistry of sulcatone reduction in Clostridia pasteurianum, C. tyrobutyricum and Lactobacillus brevis suggest that there may be at least two sulcatone reductases with different stereospecificities.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number:

References:

1. Belan, A., Botle, J., Fauve, A., Gourcy, J.G. and Veschambre, H. Use of biological systems for the preparation of chiral molecules. 3. An application in pheromone synthesis: Preparation of sulcatol enantiomers. J. Org. Chem. 52 (1987) 256-260.

2. Tidswell, E.C., Salter, G.J., Kell, D.B. and Morris, J.G. Enantioselectivity of sulcatone reduction by some anaerobic bacteria. Enzyme Microb. Technol. 21 (1997) 143-147.

3. Tidswell, E.C., Thompson, A.N. and Morris, J.G. Selection in chemostat culture of a mutant strain of Clostridium tryobutyricum improved in its reduction of ketones. J. Appl. Microbiol. Biotechnol. 35 (1991) 317-322.

EC 1.1.1.268

Common name: 2-(R)-hydroxypropyl-CoM dehydrogenase

Reaction: 2-(R)-hydroxypropyl-CoM + NAD⁺ = 2-oxopropyl-CoM + NADH + H⁺

For diagram click here.

Glossary:
coenzyme M (CoM) = 2-mercaptoethanesulfonate

Other name(s): 2-(2-(R)-hydroxypropylthio)ethanesulfonate dehydrogenase

Systematic name: 2-[2-(R)-hydroxypropylthio]ethanesulfonate:NAD⁺ oxidoreductase

Comments: The enzyme is highly specific for (R)-2-hydroxyalkyl thioethers of CoM, in contrast to EC 1.1.1.269, 2-(S)-hydroxypropyl-CoM dehydrogenase, which is highly specific for the (S)-enantiomer. This enzyme forms component III of a four-component enzyme system {comprising EC.4.2.99.19 (2-hydroxypropyl-CoM lyase; component I), EC 1.8.1.5 [2-oxopropyl-CoM reductase (carboxylating); component II], EC 1.1.1.268 [2-(R)-hydroxypropyl-CoM dehydrogenase; component III] and EC 1.1.1.269 [2-(S)-hydroxypropyl-CoM dehydrogenase; component IV]} that is involved in epoxyalkane carboxylation in Xanthobacter sp. strain Py2.

References:

1. Allen, J.R., Clark, D.D., Krum, J.G. and Ensign, S.A. A role for coenzyme M (2-mercaptoethanesulfonic acid) in a bacterial pathway of aliphatic epoxide carboxylation. Proc. Natl. Acad. Sci. USA 96 (1999) 8432-8437. [PMID: 10411892]

EC 1.1.1.269

Common name: 2-(S)-hydroxypropyl-CoM dehydrogenase

Reaction: 2-(S)-hydroxypropyl-CoM + NAD⁺ = 2-oxopropyl-CoM + NADH + H⁺

For diagram click here.

Glossary:
coenzyme M (CoM) = 2-mercaptoethanesulfonate

Other name(s): 2-(2-(S)-hydroxypropylthio)ethanesulfonate dehydrogenase

Systematic name: 2-[2-(S)-hydroxypropylthio]ethanesulfonate:NAD⁺ oxidoreductase

Comments: The enzyme is highly specific for (S)-2-hydroxyalkyl thioethers of CoM, in contrast to EC 1.1.1.268, 2-(R)-hydroxypropyl-CoM dehydrogenase, which is highly specific for the (R)-enantiomer. This enzyme forms component IV of a four-component enzyme system {comprising EC.4.2.99.19 (2-hydroxypropyl-CoM lyase; component I), EC 1.8.1.5 [2-oxopropyl-CoM reductase (carboxylating); component II], EC 1.1.1.268 [2-(R)-hydroxypropyl-CoM dehydrogenase; component III] and EC 1.1.1.269 [2-(S)-hydroxypropyl-CoM dehydrogenase; component IV]} that is involved in epoxyalkane carboxylation in Xanthobacter sp. strain Py2.

References:

1. Allen, J.R., Clark, D.D., Krum, J.G. and Ensign, S.A. A role for coenzyme M (2-mercaptoethanesulfonic acid) in a bacterial pathway of aliphatic epoxide carboxylation. Proc. Natl. Acad. Sci. USA 96 (1999) 8432-8437. [PMID: 10411892]

*EC 1.1.3.8

Common name: L-gulonolactone oxidase

Reaction: L-gulono-1,4-lactone + O₂ = L-xylo-hex-3-ulonolactone + H₂O₂

Other name(s): L-gulono-gamma-lactone: O₂ oxidoreductase; L-gulono-γ-lactone oxidase; L-gulono-gamma-lactone:oxidoreductase

Systematic name: L-gulono-1,4-lactone:oxygen 3-oxidoreductase

Comments: A flavoprotein (FAD). The product spontaneously isomerizes to L-ascorbate.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9028-79-9

References:

1. Isherwood, F.A., Mapson, L.W. and Chen, Y.T. Synthesis of L-ascorbic acid in rat liver homogenates. Conversion of L-gulono- and L-galactono-γ-lactone and the respective acids into L-ascorbic acid. Biochem. J. 76 (1960) 157-171.

2. Kiuchi, K., Noshikimi, M. and Yagi, K. Purification and characterization of L-gulonolactone oxidase from chicken kidney microsomes. Biochemistry 21 (1982) 5076.

EC 1.3.1.70

Common name: δ¹⁴-sterol reductase

Reaction: 4,4-dimethyl-5α-cholesta-8,24-dien-3β-ol + NADP⁺ = 4,4-dimethyl-5α-cholesta-8,14,24-trien-3β-ol + NADPH + H⁺

For diagram click here.

Systematic name: 4,4-dimethyl-5α-cholesta-8,24-dien-3β-ol:NADP⁺ δ¹⁴-oxidoreductase

Comments: This enzyme acts on a range of steroids with a 14(15)-double bond.

References:

1. Bottema, C.K. and Parks, L.W. δ¹⁴-Sterol reductase in Saccharomyces cerevisiae. Biochim. Biophys. Acta 531 (1978) 301-307. [PMID: 32908]

2. Paik, Y.K., Trzaskos, J.M., Shafice, A. and Gaylor, J.L. Microsomal enzymes of cholesterol biosynthesis from lanosterol. Characterization, solubilization, and partial purification of NADPH-dependent δ^8,14-steroid 14-reductase. J. Biol. Chem. 259 (1984) 13413-13423. [PMID: 6444198]

EC 1.3.1.71

Common name: δ^24(241)-sterol reductase

Reaction: ergosterol + NADP⁺ = ergosta-5,7,22,24(24¹)-tetraen-3β-ol + NADPH + H⁺

For diagram click here.

Other names: sterol δ²⁴⁽²⁸⁾-reductase; sterol δ²⁴⁽²⁸⁾-methylene reductase

Systematic name: ergosterol:NADP⁺ δ^24(241)-oxidoreductase

Comments: Acts on a range of steroids with a 24(24¹)-double bond.

References:

1. Neal, W.D. and Parks, L.W. Sterol 24(28) methylene reductase in Saccharomyces cerevisiae. J. Bacteriol. 129 (1977) 1375-1378. [PMID: 14922]

EC 1.3.1.72

Common name: δ²⁴-sterol reductase

Reaction: 5α-cholest-7-en-3β-ol + NADP⁺ = 5α-cholesta-7,24-dien-3β-ol + NADPH + H⁺

For diagram click here.

Glossary:
desmosterol = cholesta-5,24-dien-3β-ol
lanosterol = 4,4,14-trimethyl-5α-cholesta-8,24-dien-3β-ol
zymostrol = 5α-cholesta-8,24-dien-3β-ol

Other names: lanosterol δ²⁴-reductase

Systematic name: sterol:NADP⁺ δ²⁴-oxidoreductase

Comments: Acts on a range of steroids with a 24(25)-double bond, including lanosterol, desmosterol and zymosterol.

References:

1. Bae, S.H. and Paik, Y.K. Cholesterol biosynthesis from lanosterol: development of a novel assay method and characterization of rat liver microsomal lanosterol δ²⁴-reductase. Biochem. J. 326 (1997) 609-616. [PMID: 9291139]

*EC 1.4.1.13

Common name: glutamate synthase (NADPH)

Reaction: 2 L-glutamate + NADP⁺ = L-glutamine + 2-oxoglutarate + NADPH + H⁺

Other name(s): glutamate (reduced nicotinamide adenine dinucleotide phosphate) synthase; L-glutamate synthase; L-glutamate synthetase; glutamate synthetase (NADP); NADPH-dependent glutamate synthase; glutamine-ketoglutaric aminotransferase; NADPH-glutamate synthase; NADPH-linked glutamate synthase; glutamine amide-2-oxoglutarate aminotransferase (oxidoreductase, NADP); L-glutamine:2-oxoglutarate aminotransferase, NADPH oxidizing

Systematic name: L-glutamate:NADP⁺ oxidoreductase (transaminating)

Comments: An iron-sulfur flavoprotein. In the reverse reaction, ammonia can act instead of glutamine, but more slowly. Formerly EC 2.6.1.53.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 37213-53-9

References:

1. Miller, R.E. and Stadtman, E.R. Glutamate synthase from Escherichia coli. An iron-sulfide flavoprotein. J. Biol. Chem. 247 (1972) 7407-7419. [PMID: 4565085]

2. Tempest, D.W., Meers, J.L. and Brown, C.M. Synthesis of glutamate in Aerobacter aerogenes by a hitherto unknown route. Biochem. J. 117 (1970) 405-407. [PMID: 5420057]

EC 1.8.1.5

Common name: 2-oxopropyl-CoM reductase (carboxylating)

Reaction: 2-mercaptoethanesulfonate + acetoacetate + NADP⁺ = 2-(2-oxopropylthio)ethanesulfonate + CO₂ + NADPH + H⁺

For diagram click here.

Other name(s): NADPH:2-(2-ketopropylthio)ethanesulfonate oxidoreductase/carboxylase; NADPH:2-ketopropyl-coenzyme M oxidoreductase/carboxylase

Systematic name: 2-mercaptoethanesulfonate,acetoacetate:NADP⁺ oxidoreductase (decarboxylating)

Comments: Also acts on thioethers longer in chain length on the oxo side, e.g. 2-oxobutyl-CoM, but this portion must be attached to CoM (2-mercaptoethanesulfonate); no CoM analogs will substitute. This enzyme forms component II of a four-component enzyme system {comprising EC.4.2.99.19 (2-hydroxypropyl-CoM lyase; component I), EC 1.8.1.5 [2-oxopropyl-CoM reductase (carboxylating); component II], EC 1.1.1.268 [2-(R)-hydroxypropyl-CoM dehydrogenase; component III] and EC 1.1.1.269 [2-(S)-hydroxypropyl-CoM dehydrogenase; component IV]} that is involved in epoxyalkane carboxylation in Xanthobacter sp. strain Py2.

References:

1. Allen, J.R., Clark, D.D., Krum, J.G. and Ensign, S.A. A role for coenzyme M (2-mercaptoethanesulfonic acid) in a bacterial pathway of aliphatic epoxide carboxylation. Proc. Natl. Acad. Sci. USA 96 (1999) 8432-8437. [PMID: 10411892]

2. Clark, D.D., Allen, J.R. and Ensign, S.A. Characterization of five catalytic activities associated with the NADPH:2-ketopropyl-coenzyme M [2-(2-ketopropylthio)ethanesulfonate] oxidoreductase/carboxylase of the Xanthobacter strain Py2 epoxide carboxylase system. Biochemistry 39 (2000) 1294-1304. [PMID: 10684609]

[EC 1.12.99.5 Deleted entry: 3,4-dihydroxyquinoline 2,4-dioxygenase. Identical to EC 1.13.11.47 (EC 1.12.99.5 created 1999, deleted 2001)]

[EC 1.13.11.21 Transferred entry: now EC 1.14.99.36, β-carotene 15,15'-monooxygenase (EC 1.13.11.21 created 1972, deleted 2001)]

EC 1.13.11.47

Common name: 3-hydroxy-4-oxoquinoline 2,4-dioxygenase

Reaction: 3-hydroxy-1H-quinolin-4-one + O₂ = N-formylanthranilate + CO

For diagram click here.

Other name(s): (1H)-3-hydroxy-4-oxoquinoline 2,4-dioxygenase; 3-hydroxy-4-oxo-1,4-dihydroquinoline 2,4-dioxygenase; 3-hydroxy-4(1H)-one, 2,4-dioxygenase; quinoline-3,4-diol 2,4-dioxygenase

Systematic name: 3-hydroxy-1H-quinolin-4-one 2,4-dioxygenase (CO-forming)

Comments: Does not contain a metal centre or organic cofactor. Fission of two C-C bonds: 2,4-dioxygenolytic cleavage with concomitant release of carbon monoxide. The enzyme from Pseudomonas putida is highly specific for this substrate.

References:

1. Bauer, I., De Beyer, A., Tsisuaka, B., Fetzner, S. and Lingens, F. A novel type of oxygenolytic ring cleavage: 2,4-Oxygenation and decarbonylation of 1H-3-hydroxy-4-oxoquinaldine and 1H-3-hydroxy-4-oxoquinoline. FEMS Microbiol. Lett. 117 (1994) 299-304.

2. Bauer, I., Max, N., Fetzner, S. and Lingens, F. 2,4-Dioxygenases catalyzing N-heterocyclic-ring cleavage and formation of carbon monoxide. Purification and some properties of 1H-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase from Arthrobacter sp. Ru61a and comparison with 1H-3-hydroxy-4-oxoquinoline 2,4-dioxygenase from Pseudomonas putida 33/1. Eur. J. Biochem. 240 (1996) 576-583. [PMID: 8856057]

3. Fischer, F., Kunne, S. and Fetzner, S. Bacterial 2,4-dioxygenases: new members of the α/β hydrolase-fold superfamily of enzymes functionally related to serine hydrolases. J. Bacteriol. 181 (1999) 5725-5733. [PMID: 10482514]

EC 1.13.11.48

Common name: 3-hydroxy-2-methyl-quinolin-4-one 2,4-dioxygenase

Reaction: 3-hydroxy-2-methyl-1H-quinolin-4-one + O₂ = N-acetylanthranilate + CO

For diagram click here.

Other name(s): (1H)-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase

Systematic name: 3-hydroxy-2-methyl-1H-quinolin-4-one 2,4-dioxygenase (CO-forming)

Comments: Does not contain a metal centre or organic cofactor. Fission of two C-C bonds: 2,4-dioxygenolytic cleavage with concomitant release of carbon monoxide. The enzyme from Arthrobacter sp. can also act on 3-hydroxy-4-oxoquinoline, forming N-formylanthranilate and CO (cf. EC 1.13.11.47, 3-hydroxy-4-oxoquinoline 2,4-dioxygenase), but more slowly.

References:

1. Bauer, I., De Beyer, A., Tsisuaka, B., Fetzner, S. and Lingens, F. A novel type of oxygenolytic ring cleavage: 2,4-Oxygenation and decarbonylation of 1H-3-hydroxy-4-oxoquinaldine and 1H-3-hydroxy-4-oxoquinoline. FEMS Microbiol. Lett. 117 (1994) 299-304.

2. Bauer, I., Max, N., Fetzner, S. and Lingens, F. 2,4-Dioxygenases catalyzing N-heterocyclic-ring cleavage and formation of carbon monoxide. Purification and some properties of 1H-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase from Arthrobacter sp. Ru61a and comparison with 1H-3-hydroxy-4-oxoquinoline 2,4-dioxygenase from Pseudomonas putida 33/1. Eur. J. Biochem. 240 (1996) 576-583. [PMID: 8856057]

3. Fischer, F., Kunne, S. and Fetzner, S. Bacterial 2,4-dioxygenases: new members of the α/β hydrolase-fold superfamily of enzymes functionally related to serine hydrolases. J. Bacteriol. 181 (1999) 5725-5733. [PMID: 10482514]

EC 1.13.11.49

Common name: chlorite O₂-lyase

Reaction: chloride + O₂ = chlorite

Other name(s): [chlorite dismutase]

Comments: Reaction occurs in the reverse direction in chlorate- and perchlorate-reducing bacteria. There is no activity when chlorite is replaced by hydrogen peroxide, perchlorate, chlorate or nitrite. The term 'chlorite dismutase' is misleading as the reaction does not involve dismutation/disproportionation. Contains iron and protoheme IX.

References:

1. van Ginkel, C.G., Rikken, G.B., Kron, A.G.M. and Kengen, S.W.M. Purification and characterization of chlorite dismutase: a novel oxygen-generating enzyme. Arch. Microbiol. 166 (1996) 321-326. [PMID: 8929278]

2. Stenklo, K., Thorell, H.D., Bergius, H., Aasa, R. and Nilsson, T. Chlorite dismutase from Ideonella dechloratans. J. Biol. Inorg. Chem. 6 (2001) 601-607. [PMID: 11472023]

[EC 1.13.12.10 Deleted entry: lysine 6-monooxygenase. reaction covered by EC 1.14.13.59, L-lysine 6-monooxygenase (NADPH) (EC 1.13.12.10 created 1989, modified 1999, deleted 2001)]

*EC 1.13.12.12

Common name: apo-β-carotenoid-14',13'-dioxygenase

Reaction: 8'-apo-β-carotenol + O₂ = 14'-apo-β-carotenal + H₂O

Systematic name: 8'-apo-β-carotenol:O₂ oxidoreductase

Comments: A thiol-dependent enzyme. Unlike EC 1.13.11.21, β-carotene-15,15'-dioxygenase, it is not active towards β-carotene. Presumably 2-methyl-6-oxohepta-2,4-dienal is also formed in this reaction.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number:

References:

1. Dmitrovskii, A.A., Gessler, N.N., Gomboeva, S.B., Ershov, Yu.V. and Bykhovsky, V.Ya. Enzymatic oxidation of β-apo-8'-carotenol to β-apo-14'-carotenal by an enzyme different from β-carotene-15,15'-dioxygenase. Biochemistry (Moscow) 62 (1997) 787-792. [PMID: 9331970]

[EC 1.13.99.5 Transferred entry: now EC 1.13.11.47, 3,4-dihydroxyquinoline 2,4-dioxygenase (EC 1.13.99.5 created 1999, deleted 2001)]

EC 1.14.11.19

Common name: leucocyanidin oxygenase

Reaction: leucocyanidin + 2-oxoglutarate + O₂ = cis- and trans-dihydroquercetins + succinate + CO₂

For diagram, click here

Other name(s): anthocyanidin synthase

Systematic name: leucocyanidin,2-oxoglutarate:oxygen oxidoreductase

Comments: The enzyme requires Fe(II) and ascorbate. It is involved in the pathway by which many flowering plants make anthocyanin (glycosylated anthocyandin) flower pigments. The intermediates are transformed into cis- and trans-dihydroquercetin [2], which the enzyme can also oxidize to quercetin. Acidification of the products gives anthocyanidin [1], which, however, may not be a natural precursor of the anthocyanins.

References:

1. Saito, K., Kobayashi, M., Gong, Z., Tanaka, Y. and Yamazaki, M. Direct evidence for anthocyanidin synthase as a 2-oxoglutarate-dependent oxygenase: molecular cloning and functional expression of cDNA from a red forma of Perilla frutescens. Plant J. 17 (1999) 181-190. [PMID: 10074715]

2. Turnbull, J.J., Sobey, W.J., Aplin, R.T., Hassan, A., Firmin, J.L., Schofield, C.J. and Prescott, A.G. Are anthocyanidins the immediate products of anthocyanidin synthase? Chem. Commun. (2000) 2473-2474.

*EC 1.14.13.41

Common name: tyrosine N-monooxygenase

Reaction: tyrosine + O₂ + NADPH + H⁺ = N-hydroxytyrosine + NADP⁺ + H₂O

N-hydroxytyrosine + O₂ + NADPH + H⁺ = N,N-dihydroxytyrosine + NADP⁺ + H₂O

This is followed by spontaneous eliminative decarboxylation:

N,N-dihydroxytyrosine = (Z)-[p-hydroxyphenylacetaldehyde oxime] + CO₂ + H₂O

For diagram click here.

Other name(s): tyrosine N-hydroxylase

Systematic name: L-tyrosine,NADPH:oxygen oxidoreductase (N-hydroxylating)

Comments: A heme-thiolate protein (P-450). The enzyme is involved in the biosynthesis of the cyanogenic glucoside dhurrin in sorghum. In the reaction some 2-(4-hydroxyphenyl)-1-nitroethane is formed as a side product.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 112692-57-6

References:

1. Halkier, B.A. and Møller, B.L. The biosynthesis of cyanogenic glucosides in higher plants. Identification of three hydroxylation steps in the biosynthesis of dhurrin in Sorghum bicolor (L.) Moench and the involvement of 1-ACI-nitro-2-(p-hydroxyphenyl)ethane as an intermediate. J. Biol. Chem. 265 (1990) 21114-21121. [PMID: 2250015]

2. Sibbesen, O., Koch, B., Halkier, B.A. and Møller, B.L. Cytochrome P-450^TYR is a multifunctional heme-thiolate enzyme catalyzing the conversion of L-tyrosine to p-hydroxyphenylacetaldehyde oxime in the biosynthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor (L.) Moench. J. Biol. Chem. 270 (1995) 3506-3511. [PMID: 7876084]

3. Bak, S., Olsen, C.E., Halkier, B.A. and Møller, B.L. Transgenic tobacco and Arabidopsis plants expressing the two multifunctional sorghum cytochrome P450 enzymes, CYP79A1 and CYP71E1, are cyanogenic and accumulate metabolites derived from intermediates in dhurrin biosynthesis. Plant Physiol. 123 (2000) 1437-1448. [PMID: 10938360]

4. Nielsen, J.S. and Møller, B.L. Cloning and expression of cytochrome P450 enzymes catalyzing the conversion of tyrosine to p-hydroxyphenylacetaldoxime in the biosynthesis of cyanogenic glucosides in Triglochin maritima. Plant Physiol. 122 (2000) 1311-1321. [PMID: 10759528]

*EC 1.14.13.59

Common name: L-lysine 6-monooxygenase (NADPH)

Reaction: L-lysine + NADPH + H⁺ + O₂ = N⁶-hydroxy-L-lysine + NADP⁺ + H₂O

Other name(s): lysine N⁶-hydroxylase

Systematic name: L-lysine, NADPH:oxygen oxidoreductase (6-hydroxylating)

Comments: A flavoprotein (FAD). The enzyme from strain EN 222 of E. coli is highly specific for L-lysine; L-ornithine and L-homolysine are, for example, not substrates.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 64295-82-5

References:

1. Plattner, H.J., Pfefferle, P., Romaguera, A., Waschutza, S. and Diekmann, H. Isolation and some properties of lysine N⁶-hydroxylase from Escherichia coli strain EN222. Biol. Met. 2 (1989) 1-5. [PMID: 2518519]

2. Macheroux, P., Plattner, H.J., Romaguera, A. and Diekmann, H. FAD and substrate analogs as probes for lysine N⁶-hydroxylase from Escherichia coli EN 222. Eur. J. Biochem. 213 (1993) 995-1002. [PMID: 8504838]

3. Thariath, A.M., Fatum, K.L., Valvano, M.A. and Viswanatha, T. Physico-chemical characterization of a recombinant cytoplasmic form of lysine: N⁶-hydroxylase. Biochim. Biophys. Acta 1203 (1993) 27-35. [PMID: 8218389]

4. De Lorenzo, V., Bindereif, A., Paw, B.H. and Neilands, J.B. Aerobactin biosynthesis and transport genes of plasmid ColV-K30 in Escherichia coli K-12. J. Bacteriol. 165 (1986) 570-578. [PMID: 2935523]

5. Marrone, L., Siemann, S., Beecroft, M. and Viswanatha, T. Specificity of lysine:N-6-hydroxylase: A hypothesis for a reactive substrate intermediate in the catalytic mechanism. Bioorg. Chem. 24 (1996) 401-406.

6. Goh, C.J., Szczepan, E.W., Menhart, N. and Viswanatha, T. Studies on lysine: N⁶-hydroxylation by cell-free system of Aerobacter aerogenes 62-1. Biochim. Biophys. Acta 990 (1989) 240-245. [PMID: 2493814]

EC 1.14.13.69

Common name: alkene monooxygenase

Reaction: propene + NADH + H⁺ + O₂ = 1,2-epoxypropane + NAD⁺ + H₂O

For diagram click here.

Other name(s): alkene epoxygenase

Systematic name: alkene,NADH:oxygen oxidoreductase

Comments: The enzyme from Xanthobacter sp. strain Py2 is a multicomponent enzyme comprising (1) an NADH reductase, which provides the reductant for O₂ activation; (2) a Rieske-type ferredoxin, which is an electron-transfer protein; (3) an oxygenase, which contains the catalytic centre for alkene epoxidation and (4) a small protein of unknown function that is essential for activity. Requires Fe(II). The enzyme oxygenates C₂ to C₆ aliphatic alkenes. With 1,2-epoxypropane as substrate, the stereospecifity of the epoxypropane formed is 95% (R) and 5% (S).

References:

1. Small, F.J. and Ensign, S.A. Alkene monooxygenase from Xanthobacter strain Py2: purification and characterization of a four-component system central to the bacterial metabolism of aliphatic alkenes. J. Biol. Chem. 272 (1997) 24913-24920. [PMID: 9312093]

2. Zhou, N.Y., Jenkins, A., Chion, C.K.N.C.K. and Leak, D.J. The alkene monooxygenase from Xanthobacter strain Py2 is closely related to aromatic monooxygenases and catalyzes aromatic monohydroxylation of benzene, toluene, and phenol. Appl. Environ. Microbiol. 65 (1999) 1589-1595. [PMID: 10103255]

3. Gallagher, S.C., Cammack, R. and Dalton, H. Alkene monooxygenase from Nocardia corallina B-276 is a member of the class of dinuclear iron proteins capable of stereospecific epoxygenation reactions. Eur. J. Biochem. 247 (1997) 635-641. [PMID: 9266707]

EC 1.14.13.70

Common name: sterol 14-demethylase

Reaction: obtusifoliol + 3 O₂ + 3 NADPH + 3 H⁺ = 4α-methyl-5α-ergosta-8,14,24(28)-trien-3β-ol + formate + 3 NADP⁺ + 3 H₂O

For diagram click here.

Glossary:
obtusifoliol = 4α,14α-dimethyl-5α-ergosta-8,24(28)-dien-3β-ol or 4α,14α-dimethyl-24-methylene-5α-cholesta-8-en-3β-ol

Other name(s): obtusufoliol 14-demethylase; lanosterol 14-demethylase; lanosterol 14α-demethylase; sterol 14α-demethylase

Systematic name: sterol,NADPH:oxygen oxidoreductase (14-methyl cleaving)

Comments: The heme-thiolate enzyme (P-450) catalyses successive hydroxylations of the 14α-methyl group and C-15, followed by elimination as formate leaving the 14(15) double bond. This enzyme acts on a range of steroids with a 14α-methyl group.

References:

1. Bak, S., Kahn, R.A., Olsen, C.E. and Halkier, B.A. Cloning and expression in Escherichia coli of the obtusifoliol 14α-demethylase of Sorghum bicolor (L.) Moench, a cytochrome P450 orthologous to the sterol 14α-demethylases (CYP51) from fungi and mammals. Plant J. 11 (1997) 191-201. [PMID: 9076987]

2. Aoyama, Y. and Yoshida, Y. Different substrate specificities of lanosterol 14α-demethylase (P450-14DM) of Saccharomyces cerevisiae and rat liver of 24-methylene-24,25-dihydrolanosterol and 24,25-dihydrolanosterol. Biochem. Biophys. Res. Commun. 178 (1991) 1064-1071. [PMID: 1872829]

3. Aoyama, Y. and Yoshida, Y. The 4β-methyl group of substrate does not affect the activity of lanosterol 14α-demethylase (P450_14DM) of yeast: differences between the substrate recognition by yeast and plant sterol 14α-demethylases. Biochem. Biophys. Res. Commun. 183 (1992) 1266-1272. [PMID: 1567403]

4. Alexander, K., Akhtar, M., Boar, R.B., McGhie, J.F. and Barton, D.H.R. The removal of the 32-carbon atom as formic acid in cholesterol biosynthesis. J. Chem. Soc. Chem. Commun. (1972) 383-385.

EC 1.14.13.71

Common name: N-methylcoclaurine 3'-monooxygenase

Reaction: (S)-N-methylcoclaurine + NADPH + H⁺ + O₂ = (S)-3'-hydroxy-N-methylcoclaurine + NADP⁺ + H₂O

For diagram click here.

Other name(s): N-methylcoclaurine 3'-hydroxylase

Systematic name: (S)-N-methylcoclaurine, NADPH:oxygen oxidoreductase (3'-hydroxylating)

Comments: A heme-thiolate protein (P-450) involved in benzylisoquinoline alkaloid synthesis in higher plants.

References:

1. Pauli, H.H. and Kutchan, T.M. Molecular cloning and functional heterologous expression of two alleles encoding (S)-N-methylcoclaurine 3'-hydroxylase (CYP80B1), a new methyl jasmonate-inducible cytochrome P-450-dependent mono-oxygenase of benzylisoquinoline alkaloid biosynthesis. Plant. J. 13 (1998) 793-801. [PMID: 9681018]

EC 1.14.99.36

Common name: β-carotene 15,15'-monooxygenase

Reaction: β-carotene + O₂ = 2 retinal

For diagram click here.

Other name(s): β-carotene 15,15'-dioxygenase, carotene dioxygenase; carotene 15,15'-dioxygenase

Systematic name: β-carotene:oxygen 15,15'-oxidoreductase (bond-cleaving)

Comments: Requires bile salts and Fe(II). The reaction proceeds in three stages, epoxidation of the 15,15'-double bond, hydration of the double bond leading to ring opening, and oxidative cleavage of the diol formed [cf. EC 1.14.15.6, cholesterol monooxygenase (side-chain-cleaving)]. Thus only one atom of the dioxygen is incorporated into retinal. Formerly EC 1.13.11.21 as it was considered to be a dioxygenase.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 37256-60-3

References:

1. Leuenberger, M.G., Engeloch-Jarret, C. and Woggon, W.D. The reaction mechanism of the enzyme-catalysed central cleavage of β-carotene to retinal. Angew. Chem. Int. Ed. 40 (2001) 2614-2616.

2. Goodman, D.S., Huang, H.S., Kanai, M. and Shiratori, T. The enzymatic conversion of all-trans β-carotene into retinal. J. Biol. Chem. 242 (1967) 3543-3554.

3. Goodman, D.S., Huang, H.S. and Shiratori, T. Mechanism of the biosynthesis of vitamin A from β-carotene. J. Biol. Chem. 241 (1966) 1929-1932. [PMID: 5946623]

*EC 1.15. ACTING ON SUPEROXIDE AS ACCEPTOR

EC 1.15.1.2

Common name: superoxide reductase

Reaction: reduced rubredoxin + superoxide + 2 H⁺ = rubredoxin + H₂O₂

Glossary entries:
rubredoxin

Other names: neelaredoxin; desulfoferrodoxin

Systematic name: rubredoxin:superoxide oxidoreductase

Comments: The enzyme contains non-heme iron.

References:

1. Jenney, F.E., Jr., Verhagen, M.F.J.M., Cui, X. and Adams, M.W.W. Anaerobic microbes: Oxygen detoxification without superoxide dismutase. Science 286 (1999) 306-309. [PMID: 10514376]

2. Yeh, A.P., Hu, Y., Jenney, F.E., Jr., Adams, M.W.W. and Rees, D.C. Structures of the superoxide reductase from Pyrococcus furiosus in the oxidized and reduced states. Biochemistry 39 (2000) 2499-2508. [PMID: 10704199]

3. Lombard, M., Fontecave, M., Touati, D. and Niviere, V. Reaction of the desulfoferrodoxin from Desulfoarculus baarsii with superoxide anion. Evidence for a superoxide reductase activity. J. Biol. Chem. 275 (2000) 115-121. [PMID: 10617593]

4. Abreu, I.A., Saraiva, L.M., Carita, J., Huber, H., Stetter, K.O., Cabelli, D. and Teixeira, M. Oxygen detoxification in the strict anaerobic archaeon Archaeoglobus fulgidus: superoxide scavenging by neelaredoxin. Mol. Microbiol. 38 (2000) 322-334. [PMID: 11069658]

*EC 1.17.99.1

Common name: 4-cresol dehydrogenase (hydroxylating)

Reaction: 4-cresol + acceptor + H₂O = 4-hydroxybenzaldehyde + reduced acceptor

Systematic name: 4-cresol:acceptor oxidoreductase (methyl-hydroxylating)

Other name(s): p-cresol-(acceptor) oxidoreductase (hydroxylating); p-cresol methylhydroxylase

Comments: A flavocytochrome c (FAD). Phenazine methosulfate can act as acceptor. A quinone methide is probably formed as intermediate. The first hydroxylation forms 4-hydroxybenzyl alcohol; a second hydroxylation converts this into 4-hydroxybenzaldehyde.

Links to other databases: BRENDA, EXPASY, KEGG, UM-BBD, WIT, CAS registry number: 66772-07-4

References:

1. Hopper, D.J. and Taylor, D.G. The purification and properties of p-cresol-(acceptor) oxidoreductase (hydroxylating), a flavocytochrome from Pseudomonas putida. Biochem. J. 167 (1977) 155-162. [PMID: 588247]

2. McIntire, W., Edmondson, D.E. and Singer, T.P. 8α-O-Tyrosyl-FAD: a new form of covalently bound flavin from p-cresol methylhydroxylase. J. Biol. Chem. 255 (1980) 6553-6555. [PMID: 7391034]

EC 1.17.99.2

Common name: ethylbenzene hydroxylase

Reaction: ethylbenzene + H₂O + acceptor = (S)-1-phenylethanol + reduced acceptor

For diagram click here.

Other names: ethylbenzene dehydrogenase

Systematic name: ethylbenzene:(acceptor) oxidoreductase

Comments: Involved in the anaerobic catabolism of ethylbenzene by denitrifying bacteria. Ethylbenzene is the preferred substrate; the enzyme from some strains oxidizes propylbenzene, 1-ethyl-4-fluorobenzene, 3-methylpent-2-ene and ethylidenecyclohexane. Toluene is not oxidized. p-Benzoquinone or ferrocenium can act as electron acceptor. Contains molybdopterin, [4Fe-4S] clusters and heme b.

References:

1. Kniemeyer, O. and Heider, J. Ethylbenzene dehydrogenase, a novel hydrocarbon-oxidising molybdenum/iron-sulfur/heme enzyme. J. Biol. Chem. 276 (2001) 21381-21386. [PMID: 11294876]

2. Johnson, H.A., Pelletier, D.A. and Spormann, A.M. Isolation and characterisation of anaerobic ethylbenzene dehydrogenase, a novel Mo-Fe-S enzyme. J. Bacteriol. 183 (2001) 4536-4542. [PMID: 11443088]

[EC 1.18.96.1 Transferred entry: now EC 1.15.1.2, superoxide reductase (EC 1.18.96.1 created 2001, deleted 2001)]

EC 1.20 ACTING ON PHOSPHORUS OR ARSENIC IN DONORS

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

EC 1.20.1.1

Common name: phosphonate dehydrogenase

Reaction: phosphonate + NAD⁺ + H₂O = phosphate + NADH + H⁺

Other name(s): NAD:phosphite oxidoreductase; phosphite dehydrogenase

Systematic name: phosphonate:NAD⁺ oxidoreductase

Comments: NADP⁺ is a poor substitute for NAD⁺ in the enzyme from Pseudomonas stutzeri WM88.

References:

1. Costas, A.M.G., White, A.K. and Metcalf, W.W. Purification and characterization of a novel phosphorus-oxidizing enzyme from Pseudomonas stutzeri WM88. J. Biol. Chem. 276 (2001) 17429-17436. [PMID: 11278981]

2. Vrtis, J.M., White, A.K., Metcalf, W.W. and van der Donk, W.A. Phosphite dehydrogenase: An unusual phosphoryl transfer reaction. J. Am. Chem. Soc. 123 (2001) 2672-2673. [PMID: 11456941]

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

EC 1.20.4.1

Common name: arsenate reductase (glutaredoxin)

Reaction: arsenate + reduced glutaredoxin = arsenite + oxidized glutaredoxin

Systematic name: glutharedoxin:arsenate oxidoreductase

Comments: A molybdoenzyme. The glutaredoxins catalyse glutathione-disulfide oxidoreductions and have a redox-active disulfide/dithiol in the active site (-Cys-Pro-Tyr-Cys-) that forms a disulfide bond in the oxidized form [2, 10]. Glutaredoxins have a binding site for glutathione, which is required to reduce them to the dithiol form [3, 6]. Thioredoxins reduced by NADPH and thioredoxin reductase can act as alternative substrates. The enzyme [1, 4, 7, 9] is part of a system for detoxifying arsenate. Although the arsenite formed is more toxic than arsenate, it can be extruded from some bacteria by EC 3.6.3.16, arsenite-transporting ATPase; in other organisms, arsenite can be methylated by EC 2.1.1.137, arsenite methyltransferase, in a pathway to non-toxic organoarsenical compounds.

References:

1. Gladysheva, T., Liu, J.Y. and Rosen, B.P. His-8 lowers the pK_a of the essential Cys-12 residue of the ArsC arsenate reductase of plasmid R773. J. Biol. Chem. 271 (1996) 33256-33260. [PMID: 8969183]

2. Gladysheva, T.B., Oden, K.L. and Rosen, B.P. Properties of the arsenate reductase of plasmid R773. Biochemistry 33 (1994) 7288-7293. [PMID: 8003492]

3. Holmgren, A. and Aslund, F. Glutaredoxin. Methods Enzymol. 252 (1995) 283-292. [PMID: 7476363]

4. Ji, G.Y., Garber, E.A.E., Armes, L.G., Chen, C.M., Fuchs, J.A. and Silver, S. Arsenate reductase of Staphylococcus aureus plasmid PI258. Biochemistry 33 (1994) 7294-7299. [PMID: 8003493 ]

5. Krafft, T. and Macy, J.M. Purification and characterization of the respiratory arsenate reductase of Chrysiogenes arsenatis. Eur. J. Biochem. 255 (1998) 647-653. [PMID: 9738904]

6. Martin, J.L. Thioredoxin - a fold for all reasons. Structure 3 (1995) 245-250. [PMID: 7788290]

7. Messens, J., Hayburn, G., Desmyter, A., Laus, G. and Wyns, L. The essential catalytic redox couple in arsenate reductase from Staphylococcus aureus. Biochemistry 38 (1999) 16857-16865. [PMID: 10606519]

8. Radabaugh, T.R. and Aposhian, H.V. Enzymatic reduction of arsenic compounds in mammalian systems: reduction of arsenate to arsenite by human liver arsenate reductase. Chem. Res. Toxicol. 13 (2000) 26-30. [PMID: 10649963]

9. Sato, T. and Kobayashi, Y. The ars operon in the skin element of Bacillus subtilis confers resistance to arsenate and arsenite. J. Bacteriol. 180 (1998) 1655-1661. [PMID: 9537360]

10. Shi, J., Vlamis-Gardikas, V., Aslund, F., Holmgren, A. and Rosen, B.P. Reactivity of glutaredoxins 1, 2, and 3 from Escherichia coli shows that glutaredoxin 2 is the primary hydrogen donor to ArsC-catalyzed arsenate reduction. J. Biol. Chem. 274 (1999) 36039-36042. [PMID: 10593884]

EC 1.20.4.2

Common name: methylarsonate reductase

Reaction: methylarsonate + 2 glutathione = methylarsonite + oxidized glutathione

Other name(s): MMA(V) reductase

Systematic name: gluthathione:methylarsonate oxidoreductase

Comments: The product, Me-As(OH)₂ (methylarsonous acid), is biologically methylated by EC 2.1.1.138, methylarsonite methyltransferase, to form cacodylic acid (dimethylarsinic acid).

References:

1. Zakharyan, R.A. and Aposhian, H.V. Enzymatic reduction of arsenic compounds in mammalian systems: the rate-limiting enzyme of rabbit liver arsenic biotransformation is MMA(V) reductase. Chem. Res. Toxicol. 12 (1999) 1278-1283. [PMID: 10604879]

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

EC 1.20.98.1

Common name: arsenate reductase (azurin)

Reaction: arsenite + H₂O + azurin_ox = arsenate + azurin_red

Other names: arsenite oxidase

Glossary entries:
Azurin: a blue copper protein found in many bacteria, which undergoes oxidation-reduction between Cu(I) and Cu(II), and transfers single electrons between enzymes.

Rieske cluster: a [2Fe-2S] cluster having Cys₂ coordination at one iron, and His₂ coordination at the other.

Systematic name: arsenite:azurin oxidoreductase

Comments: Contains a molybdopterin centre comprising two molybdopterin guanosine dinucleotide cofactors bound to molybdenum, a [3Fe-4S] cluster and a Rieske-type [2Fe-2S] cluster. Also uses a c-type cytochrome or O₂ as acceptors.

References:

1. Anderson, G.L., Williams, J. and Hille, R. The purification and characterization of arsenite oxidase from Alcaligenes faecalis, a molybdenum-containing hydroxylase. J. Biol. Chem. 267 (1992) 23674-23682. [PMID: 1331097]

2. Ellis, P.J., Conrads, T., Hille, R. and Kuhn, P. Crystal structure of the 100 kDa arsenite oxidase from Alcaligenes-faecalis in two crystal forms at 1.64 Å and 2.03 Å. Structure 9 (2001) 125-132. [PMID: 11250197]

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

EC 1.20.99.1

Common name: arsenate reductase (donor)

Reaction: arsenite + acceptor = arsenate + reduced acceptor

Systematic name: arsenate:(acceptor) oxidoreductase

Comments: Benzyl viologen can act as an acceptor. Unlike EC 1.20.4.1, arsenate reductase (glutaredoxin), reduced glutaredoxin cannot serve as a reductant.

References:

1. Krafft, T. and Macy, J.M. Purification and characterization of the respiratory arsenate reductase of Chrysiogenes arsenatis. Eur. J. Biochem. 255 (1998) 647-653. [PMID: 9738904]

2. Radabaugh, T.R. and Aposhian, H.V. Enzymatic reduction of arsenic compounds in mammalian systems: reduction of arsenate to arsenite by human liver arsenate reductase. Chem. Res. Toxicol. 13 (2000) 26-30. [PMID: 10649963]

[EC 1.97.1.5 Transferred entry: now EC 1.20.4.1, arsenate reductase (glutaredoxin) (EC 1.97.1.5 created 2000, deleted 2001)]

[EC 1.97.1.6 Transferred entry: now EC 1.20.99.1, arsenate reductase (donor) (EC 1.97.1.6 created 2000, deleted 2001)]

[EC 1.97.1.7 Transferred entry: now EC 1.20.4.2, methylarsonate reductase (EC 1.97.1.7 created 2000, deleted 2001)]

*EC 2.1.1.41

Common name: sterol 24-C-methyltransferase

Reaction: S-adenosyl-L-methionine + 5α-cholesta-8,24-dien-3β-ol = S-adenosyl-L-homocysteine + 24-methylene-5α-cholest-8-en-3β-ol

For diagram click here.

Glossary entries:
desmosterol = cholesta-5,24-dien-3β-ol
zymostrol = 5α-cholesta-8,24-dien-3β-ol

Other name(s): δ²⁴-methyltransferase; δ²⁴-sterol methyltransferase; zymosterol-24-methyltransferase; S-adenosyl-4-methionine:sterol δ²⁴-methyltransferase; SMT₁; 24-sterol C-methyltransferase; S-adenosyl-L-methionine:δ²⁴⁽²³⁾-sterol methyltransferase; phytosterol methyltransferase

Systematic name: S-adenosyl-L-methionine:zymosterol 24-C-methyltransferase

Comments: Requires glutathione. Acts on a range of sterols with a 24(25)-double bond in the sidechain. While zymosterol is the preferred substrate it also acts on desmosterol, 5α-cholesta-7,24-dien-3β-ol, 5α-cholesta-5,7,24-trien-3β-ol, 4α-methylzymosterol and others. S-Adenosyl-L-methionine attacks the Si-face of the 24(25) double bond and the C-24 hydrogen is transferred to C-25 on the Re face of the double bond.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 37257-07-1

References:

1. Moore, J.T., Jr. and Gaylor, J.L. Isolation and purification of an S-adenosylmethionine: δ²⁴-sterol methyltransferase from yeast. J. Biol. Chem. 244 (1969) 6334-6340. [PMID: 5354959]

2. Venkatramesh, M., Guo, D., Jia, Z. and Nes, W.D. Mechanism and structural requirements for transformations of substrates by the S-adenosyl-L-methionine:δ²⁴⁽²⁵⁾-sterol methyl transferase enzyme from Saccharomyces cerevisiae. Biochim. Biophys. Acta 1299 (1996) 313-324. [PMID: 8597586]

3. Tong, Y., McCourt, B.S., Guo, D., Mangla, A.T., Zhou, W.X., Jenkins, M.D., Zhou, W., Lopez, M. and Nes, W.D., Stereochemical features of C-methylation on the path to δ²⁴⁽²⁸⁾-methylene and δ²⁴⁽²⁸⁾-ethylidene sterols: studies on the recombinant phytosterol methyl transferase from Arabidopsis thaliana. Tetrahedron Lett. 38 (1997) 6115-6118.

4. Bouvier-Navé, P., Husselstein, T. and Benveniste, P. Two families of sterol methyltransferases are involved in the first and the second methylation steps of plant biosynthesis. Eur. J. Biochem. 256 (1998) 88-96. [PMID: 9746350]

5. Nes, W.D., McCourt, B.S., Zhou, W., Ma, J., Marshall, J.A., Peek, L.A. and Brennan, M. Overexpression, purification, and stereochemical studies of the recombinant S-adenosyl-L-methionine:δ²⁴⁽²⁵⁾- to δ²⁴⁽²⁸⁾-sterol methyl transferase enzyme from Saccharomyces cerevisiae sterol methyl transferase. Arch. Biochem. Biophys. 353 (1998) 297-311. [PMID: 9606964]

EC 2.1.1.142

Common name: cycloartenol 24-C-methyltransferase

Reaction: S-adenosyl-L-methionine + cycloartenol = S-adenosyl-L-homocysteine + (24R)-24-methylcycloarta-8,25-dien-3β-ol

For diagram click here.

Other names: sterol C-methyltransferase

Systematic name: S-adenosyl-L-methionine:cycloartenol 24-C-methyltransferase

Comments: S-Adenosyl-L-methionine methylates the Si face of the 24(25)-double bond with elimination of a hydrogen atom from the pro-Z methyl group at C-25.

References:

1. Mangla, A.T. and Nes, W.D. Sterol C-methyl transferase from Prototheca wickerhamii mechanism, sterol specificity and inhibition. Bioorg. Med. Chem. 8 (2000) 925-36. [PMID: 10882005]

EC 2.1.1.143

Common name: 24-methylenesterol C-methyltransferase

Reaction: S-adenosyl-L-methionine + 24-methylenelophenol = S-adenosyl-L-homocysteine + (Z)-24-ethylidenelophenol

For diagram click here.

Glossary:
lophenol = 4α-methyl-5α-cholesta-7-en-3β-ol

Other names: SMT₂; 24-methylenelophenol C-24¹-methyltransferase

Systematic name: S-adenosyl-L-methionine:24-methylenelophenol C-methyltransferase

Comments: This is the second methylation step of plant sterol biosynthesis (cf EC 2.1.1.142, cycloartenol 24¹-C-methyltransferase).

References:

1. Bouvier-Navé, P., Husselstein, T. and Benveniste, P. Two families of sterol methyltransferases are involved in the first and the second methylation steps of plant biosynthesis. Eur. J. Biochem. 256 (1998) 88-96. [PMID: 9746350]

*EC 2.3.1.117

Common name: 2,3,4,5-tetrahydropyridine-2,6-dicarboxylate N-succinyltransferase

Reaction: succinyl-CoA + (R)-2,3,4,5-tetrahydropyridine-2,6-dicarboxylate + H₂O = CoA + (R)-2-(succinylamino)-6-oxoheptanedioate

For diagram click here.

Glossary:
dipicolinate = pyridine-2,6-dicarboxylate

Other name(s): tetrahydropicolinate succinylase; tetrahydrodipicolinate N-succinyltransferase; tetrahydrodipicolinate succinyltransferase; succinyl-CoA:tetrahydrodipicolinate N-succinyltransferase

Systematic name: succinyl-CoA:2,3,4,5-tetrahydropyridine-2,6-dicarboxylate N-succinyltransferase

Comments: Involved in the biosynthesis of lysine in bacteria (including cyanobacteria) and higher plants. The 1992 edition of the Enzyme List erroneously gave the name 2,3,4,5-tetrahydropyridine-2-carboxylate N-succinyltransferase to this enzyme.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 88086-34-4

References:

1. Simms, S.A., Voige, W.H. and Gilvarg, C. Purification and characterization of succinyl-CoA: tetrahydrodipicolinate N-succinyltransferase from Escherichia coli. J. Biol. Chem. 259 (1984) 2734-2741. [PMID: 6365916]

*EC 2.4.1.65

Common name: 3-α-galactosyl-N-acetylglucosaminide 4-α-L-fucosyltransferase

Reaction: GDP-L-fucose + β-D-galactosyl-(13)-N-acetyl-D-glucosaminyl-R = GDP + β-D-galactosyl-(13)-[α-L-fucosyl-(14)]-N-acetyl-D-glucosaminyl-R

Other name(s): blood group Lewis α-4-fucosyltransferase; guanosine diphosphofucose-β-acetylglucosaminylsaccharide 4-α-L-fucosyltransferase; α(1,3/1,4) fucosyltransferase III; α-(14)-L-fucosyltransferase; α-4-L-fucosyltransferase; β-acetylglucosaminylsaccharide fucosyltransferase; blood-group substance Le^a-dependent fucosyltransferase; guanosine diphosphofucose-glycoprotein 4-α-fucosyltransferase; guanosine diphosphofucose-glycoprotein 4-α-L-fucosyltransferase; Lewis blood group α-(13/4)-fucosyltransferase; Lewis α-(13/4)-fucosyltransferase; FucT-II; (Le^a)-dependent (α-3/4)-fucosyltransferase; Lewis α-(13/4)-fucosyltransferase; Lewis(Le) blood group gene-dependent α-(13/4)-L-fucosyltransferase

Systematic name: GDP-L-fucose:3-β-D-galactosyl-N-acetyl-D-glucosaminyl-R 4^I-α-L-fucosyltransferase

Comments: This enzyme is the product of the Lewis blood group gene but has a persistent 3-fucosyltransferase activity towards the glucose residue in lactose.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 37277-69-3

References:

1. Prieels, J.-P., Monnom, D., Dolmans, M., Beyer, T.A. and Hill, R.L. Co-purification of the Lewis blood group N-acetylglucosaminide α14 fucosyltransferase and an N-acetylglucosaminide α13 fucosyltransferase from human milk. J. Biol. Chem. 256 (1981) 10456-10463. [PMID: 7287719]

*EC 2.4.1.101

Common name: α-1,3-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase

Reaction: UDP-N-acetyl-D-glucosamine + 3-(α-D-mannosyl)-β-D-mannosyl-R = UDP + 3-(2-[N-acetyl-β-D-glucosaminyl]-α-D-mannosyl)-β-D-mannosyl-R; α-1,3-mannosyl-glycoprotein β-1,2-N-acetylglucosaminyltransferase

For diagram click here.

Other name(s): N-acetylglucosaminyltransferase I; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase I; uridine diphosphoacetylglucosamine-α-1,3-mannosylglycoprotein β-1,2-N-acetylglucosaminyltransferase; UDP-N-acetylglucosaminyl:α-1,3-D-mannoside-β-1,2-N-acetylglucosaminyltransferase I; UDP-N-acetylglucosaminyl:α-3-D-mannoside β-1,2-N-acetylglucosaminyltransferase I; α-1,3-mannosyl-glycoprotein β-1,2-N-acetylglucosaminyltransferase

Systematic name: UDP-N-acetyl-D-glucosamine:3-(α-D-mannosyl)-β-D-mannosyl-glycoprotein 2-β-N-acetyl-D-glucosaminyltransferase

Comments: R represents the remainder of the N-linked oligosaccharide in the glycoprotein acceptor. Note that this enzyme acts before N-acetylglucosaminyltransferases II, III, IV, V and VI (click here for diagram).

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 102576-81-8

References:

1. Harpaz, N. and Schachter, H. Control of glycoprotein synthesis. Bovine colostrum UDP-N-acetylglucosamine:α-D-mannoside β2-N-acetylglucosaminyltransferase I. Separation from UDP-N-acetylglucosamine:α-D-mannoside β2-N-acetylglucosaminyltransferase II, partial purification, and substrate specificity. J. Biol. Chem. 255 (1980) 4885-4893. [PMID: 6445358]

2. Mendicino, J., Chandrasekaran, E.V., Anumula, K.R. and Davila, M. Isolation and properties of α-D-mannose:β-1,2-N-acetylglucosaminyltransferase from trachea mucosa. Biochemistry 20 (1981) 967-976. [PMID: 6452163]

3. Miyagi, T. and Tsuiki, S. Studies on UDP-N-acetylglucosamine : α-mannoside β-N-acetylglucosaminyltransferase of rat liver and hepatomas. Biochim. Biophys. Acta 661 (1981) 148-157. [PMID: 6170335]

4. Oppenheimer, C.L., Eckhardt, A.E. and Hill, R.L. The nonidentity of porcine N-acetylglucosaminyltransferases I and II. J. Biol. Chem. 256 (1981) 11477-11482. [PMID: 6457827]

5. Oppenheimer, C.L. and Hill, R.L. Purification and characterization of a rabbit liver α13 mannoside β12 N-acetylglucosaminyltransferase. J. Biol. Chem. 256 (1981) 799-804. [PMID: 6450208]

6. Schachter, H., Narasimhan, S., Gleeson, P. and Vella, G. Glycosyltransferases involved in elongation of N-glycosidically linked oligosaccharides of the complex or N-acetyllactosamine type. Methods Enzymol. 98 (1983) 98-134. [PMID: 6366476]

7. Vella, G.J., Paulsen, H. and Schachter, H. Control of glycoprotein synthesis. IX. A terminal Man αl-3Man β1- sequence in the substrate is the minimum requirement for UDP-N-acetyl-D-glucosamine: α-D-mannoside (GlcNAc to Man α1-3) β2-N-acetylglucosaminyltransferase I. Can. J. Biochem. Cell Biol. 62 (1984) 409-417. [PMID: 6235906]

8. Unligil, U.M., Zhou, S., Yuwaraj, S., Sarkar, M., Schachter, H. and Rini, J.M. X-ray crystal structure of rabbit N-acetylglucosaminyltransferase I: catalytic mechanism and a new protein superfamily. EMBO J. 19 (2000) 5269-5280. [PMID: 11032794]

*EC 2.4.1.142

Common name: chitobiosyldiphosphodolichol β-mannosyltransferase

Reaction: GDPmannose + chitobiosyldiphosphodolichol = GDP + β-1,4-D-mannosylchitobiosyldiphosphodolichol

Other name(s): guanosine diphosphomannose-dolichol diphosphochitobiose mannosyltransferase; GDP-mannose-dolichol diphosphochitobiose mannosyltransferase

Systematic name: GDPmannose:chitobiosyldiphosphodolichol β-D-mannosyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 83380-85-2

References:

1. Sharma, C.B., Lehle, L. and Tanner, W. Solubilization and characterization of the initial enzymes of the dolichol pathway from yeast. Eur. J. Biochem. 126 (1982) 319-325. [PMID: 6215245]

2. Takahashi, T., Honda, R. and Nishikawa, Y. Cloning of the human cDNA which can complement the defect of the yeast mannosyltransferase I-deficient mutant alg 1. Glycobiology 10 (2000) 321-327. [PMID: 10704531]

*EC 2.4.1.143

Common name: α-1,6-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase

Reaction: UDP-N-acetyl-D-glucosamine + 6-(α-D-mannosyl)-β-D-mannosyl-R = UDP + 6-(2-[N-acetyl-β-D-glucosaminyl]-α-D-mannosyl)-β-D-mannosyl-R

For diagram click here.

Other name(s): N-acetylglucosaminyltransferase II; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase II; acetylglucosaminyltransferase II; uridine diphosphoacetylglucosamine-mannoside α16-acetylglucosaminyltransferase; uridine diphosphoacetylglucosamine-α-1,6-mannosylglycoprotein β-1-2-N-acetylglucosaminyltransferase; uridine diphosphoacetylglucosamine-α-D-mannoside β1-2-acetylglucosaminyltransferase; UDP-GlcNAc:mannoside α1-6 acetylglucosaminyltransferase; α-1,6-mannosyl-glycoprotein β-1,2-N-acetylglucosaminyltransferase

Systematic name: UDP-N-acetyl-D-glucosamine:6-(α-D-mannosyl)-β-D-mannosyl-glycoprotein 2-β-N-acetyl-D-glucosaminyltransferase

Comments: R represents the remainder of the N-linked oligosaccharide in the glycoprotein acceptor. Note that this enzyme acts after N-acetylglucosaminyltransferase I but before N-acetylglucosaminyltransferases III, IV, V and VI (click here for diagram).

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 105913-04-0

References:

1. Bendiak, B. and Schacter, H. Control of glycoprotein synthesis. Purification of UDP-N-acetylglucosamine:α-D-mannoside β1-2 N-acetylglucosaminyltransferase II from rat liver. J. Biol. Chem. 262 (1987) 5775-5783. [PMID: 2952644]

2. Harpaz, N. and Schachter, H. Control of glycoprotein synthesis. Bovine colostrum UDP-N-acetylglucosamine:α-D-mannoside β2-N-acetylglucosaminyltransferase I. Separation from UDP-N-acetylglucosamine:α-D-mannoside β2-N-acetylglucosaminyltransferase II, partial purification, and substrate specificity. J. Biol. Chem. 255 (1980) 4885-4893. [PMID: 6445358]

3. Mendicino, J., Chandrasekaran, E.V., Anumula, K.R. and Davila, M. Isolation and properties of α-D-mannose:β-1,2-N-acetylglucosaminyltransferase from trachea mucosa. Biochemistry 20 (1981) 967-976. [PMID: 6452163]

4. Oppenheimer, C.L., Eckhardt, A.E. and Hill, R.L. The nonidentity of porcine N-acetylglucosaminyltransferases I and II. J. Biol. Chem. 256 (1981) 11477-11482. [PMID: 6457827]

5. Schachter, H., Narasimhan, S., Gleeson, P. and Vella, G. Glycosyltransferases involved in elongation of N-glycosidically linked oligosaccharides of the complex or N-acetyllactosamine type. Methods Enzymol. 98 (1983) 98-134. [PMID: 6366476]

6. Bendiak, B. and Schachter, H. Control of glycoprotein synthesis. Kinetic mechanism, substrate specificity, and inhibition characteristics of UDP-N-acetylglucosamine:α-D-mannoside β-1-2 N-acetylglucosaminyltransferase II from rat liver. J. Biol. Chem. 262 (1987) 5784-5790. [PMID: 2952644]

*EC 2.4.1.144

Common name: β-1,4-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase

Reaction: UDP-N-acetyl-D-glucosamine + β-D-mannosyl-R = UDP + 4-(N-acetyl-β-D-glucosaminyl)-β-D-mannosyl-R

For diagram click here.

Other name(s): N-acetylglucosaminyltransferase III; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase III; uridine diphosphoacetylglucosamine-glycopeptide β4-acetylglucosaminyltransferase III; β-1,4-mannosyl-glycoprotein β-1,4-N-acetylglucosaminyltransferase

Systematic name: UDP-N-acetyl-D-glucosamine:β-D-mannosyl-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase

Comments: R represents the remainder of the N-linked oligosaccharide in the glycoprotein acceptor (click here for diagram). The action of this enzyme probably prevents further attachment of N-acetylglucosamine residues to the growing carbohydrate chain.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 83744-93-8

References:

1. Narasimhan, S. Control of glycoprotein synthesis. UDP-GlcNAc:glycopeptide β4-N-acetylglucosaminyltransferase III, an enzyme in hen oviduct which adds GlcNAc in β1-4 linkage to the β-linked mannose of the trimannosyl core of N-glycosyl oligosaccharides. J. Biol. Chem. 257 (1982) 10235-10242. [PMID: 6213618]

2. Schachter, H., Narasimhan, S., Gleeson, P. and Vella, G. Glycosyltransferases involved in elongation of N-glycosidically linked oligosaccharides of the complex or N-acetyllactosamine type. Methods Enzymol. 98 (1983) 98-134. [PMID: 6366476]

*EC 2.4.1.145

Common name: α-1,3-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase

Reaction: UDP-N-acetyl-D-glucosamine + 3-(2-[N-acetyl-β-D-glucosaminyl]-α-D-mannosyl)-β-D-mannosyl-R = UDP + 3-(2,4-bis[N-acetyl-β-D-glucosaminyl]-α-D-mannosyl)-β-D-mannosyl-R

For diagram click here.

Other name(s): N-acetylglucosaminyltransferase IV; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase IV; β-acetylglucosaminyltransferase IV; uridine diphosphoacetylglucosamine-glycopeptide β4-acetylglucosaminyltransferase IV; α-1,3-mannosylglycoprotein β-1,4-N-acetylglucosaminyltransferase

Systematic name: UDP-N-acetyl-D-glucosamine:3-[2-(N-acetyl-β-D-glucosaminyl)-α-D-mannosyl]-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase

Comments: R represents the remainder of the N-linked oligosaccharide in the glycoprotein acceptor (click here for diagram). The best acceptor for this enzyme is probably the same as that favoured by EC 2.4.1.144, β-1,4-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 86498-16-0

References:

1. Gleeson, P.A. and Schachter, H. Control of glycoprotein synthesis. J. Biol. Chem. 258 (1983) 6162-6173. [PMID: 6222042]

*EC 2.4.1.155

Common name: α-1,6-mannosyl-glycoprotein 6-β-N-acetylglucosaminyltransferase

Reaction: UDP-N-acetyl-D-glucosamine + 6-(2-[N-acetyl-β-D-glucosaminyl]-α-D-mannosyl)-β-D-mannosyl-R = UDP + 6-(2,6-bis[N-acetyl-β-D-glucosaminyl]-α-D-mannosyl)-β-D-mannosyl-R

For diagram click here.

Other name(s): N-acetylglucosaminyltransferase V; α-mannoside β-1,6-N-acetylglucosaminyltransferase; uridine diphosphoacetylglucosamine-α-mannoside β16-acetylglucosaminyltransferase; UDP-N-acetylglucosamine:α-mannoside-β1,6 N-acetylglucosaminyltransferase; α-1,3(6)-mannosylglycoprotein β-1,6-N-acetylglucosaminyltransferase

Systematic name: UDP-N-acetyl-D-glucosamine:6-[2-(N-acetyl-β-D-glucosaminyl)-α-D-mannosyl]-glycoprotein 6-β-N-acetyl-D-glucosaminyltransferase

Comments: R represents the remainder of the N-linked oligosaccharide in the glycoprotein acceptor (click here for diagram).

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 8358-90-3

References:

1. Cummings, R.D., Trowbridge, I.S. and Kornfeld, S. A mouse lymphoma cell line resistant to the leukoagglutinating lectin from Phaseolus vulgaris is deficient in UDP-GlcNAc: α-D-mannoside β1,6 N-acetylglucosaminyltransferase. J. Biol. Chem. 257 (1982) 13421-13427. [PMID: 6216250]

2. Hindsgaul, O., Tahir, S.H., Srivastava, O.P. and Pierce, M. The trisaccharide β-D-GlcpNAc-(1-2)-α-D-Manp-(1-6)-β-D-Manp, as its 8-methoxycarbonyloctyl glycoside, is an acceptor selective for N-acetylglucosaminyltransferase V. Carbohydr. Res. 173 (1988) 263-272. [PMID: 2834054]

*EC 2.4.1.201

Common name: α-1,6-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase

Reaction: UDP-N-acetyl-D-glucosamine + 2,6-bis(N-acetyl-β-D-glucosaminyl)-α-D-mannosyl-R = UDP + 2,4,6-tris(N-acetyl-β-D-glucosaminyl)-α-D-mannosyl-R

For diagram click here.

Other name(s): N-acetylglucosaminyltransferase VI; N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase VI; uridine diphosphoacetylglucosamine-glycopeptide β-14-acetylglucosaminyltransferase VI; mannosyl-glycoprotein β-1,4-N-acetylglucosaminyltransferase

Systematic name: UDP-N-acetyl-D-glucosamine:2,6-bis(N-acetyl-β-D-glucosaminyl)-α-D-mannosyl-glycoprotein 4-β-N-acetyl-D-glucosaminyltransferase

Comments: R represents the remainder of the N-linked oligosaccharide in the glycoprotein acceptor (click here for diagram).

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 119699-68-2

References:

1. Brockhausen, I., Hull, E., Hindsgaul, O., Schachter, H., Shah, R.N., Michnick, S.W. and Carver, J.P. Control of glycoprotein synthesis. Detection and characterization of a novel branching enzyme from hen oviduct, UDP-N-acetylglucosamine:GlcNAc β1-6 (GlcNAc β1-2)Man α-R (GlcNAc to Man) β-4-N-acetylglucosaminyltransferase VI. J. Biol. Chem. 264 (1989) 11211-11221. [PMID: 2525556]

2. Taguchi, T., Ogawa, T., Inoue, S., Inoue, Y., Sakamoto, Y., Korekane, H., and Taniguchi, N. Purification and characterization of UDP-GlcNAc:GlcNAcβ1-6(GlcNAcβ1-2)Manα1-R [GlcNAc to Man]-β1,4-N-acetylglucosaminyltransferase VI from hen oviduct. J. Biol. Chem. 275 (2000) 32598-32602. [PMID: 10903319]

*EC 2.4.1.203

Common name: trans-zeatin O-β-D-glucosyltransferase

Reaction: UDPglucose + trans-zeatin = UDP + O-β-D-glucosyl-trans-zeatin

Glossary:
zeatin

Other name(s): zeatin O-β-D-glucosyltransferase; uridine diphosphoglucose-zeatin O-glucosyltransferase; zeatin O-glucosyltransferase

Systematic name: UDPglucose:trans-zeatin O-β-D-glucosyltransferase

Comments: Unlike EC 2.4.1.215, cis-zeatin O-β-D-glucosyltransferase, UDPxylose can also act as donor (cf. EC 2.4.1.204 zeatin O-β-D-xylosyltransferase).

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 123644-76-8

References:

1. Dixon, S.C., Martin, R.C., Mok, R.C., Shaw, G. and Mok, D.W.S. Zeatin glycosylation enzymes in Phaseolus - isolation of O-glucosyltransferase from Phaseolus lunatus and comparison to O-xylosyltransferase from P. vulgaris. Plant Physiol. 90 (1989) 1316-1321.

EC 2.4.1.215

Common name: cis-zeatin O-β-D-glucosyltransferase

Reaction: UDPglucose + cis-zeatin = UDP + O-β-D-glucosyl-cis-zeatin

Glossary:
zeatin

Systematic name: UDPglucose:cis-zeatin O-β-D-glucosyltransferase

Comments: The enzyme from maize can use cis-zeatin and UDPglucose as substrates, but not cis-ribosylzeatin, trans-zeatin or trans-ribosylzeatin. Unlike EC 2.4.1.203, trans-zeatin O-β-D-glucosyltransferase, UDPxylose cannot act as a donor.

References:

1. Martin, R.C., Mok, M.C., Habben, J.E. and Mok, D.W.S. A maize cytokinin gene encoding an O-glucosyltransferase specific to cis-zeatin. Proc. Natl. Acad. Sci. USA 98 (2001) 5922-5926. [PMID: 11331778]

EC 2.4.1.216

Common name: trehalose 6-phosphate phosphorylase

Reaction: trehalose 6-phosphate + phosphate = glucose 6-phosphate + β-D-glucose 1-phosphate

Systematic name: trehalose 6-phosphate:phosphate β-D-glucosyltransferase

Comments: The enzyme from Lactococcus lactis is specific for trehalose 6-phosphate. Differs from EC 2.4.1.64, α,α-trehalose phosphorylase, in that trehalose is not a substrate.

References:

1. Andersson, U., Levander, F. and Radstrom, P. Trehalose 6-phosphate phosphorylase is part of a novel metabolic pathway for trehalose utilization in Lactococcus lactis. J. Biol. Chem. 276 (2001) 42707-42713. [PMID: 11553642]

*EC 2.5.1.2

Common name: thiamine pyridinylase

Reaction: thiamine + pyridine = 1-[(4-amino-2-methylpyrimidin-5-yl)methyl]pyridinium + 4-methyl-5-(2-hydroxyethyl)thiazole

For diagram click here.

Other name(s): pyrimidine transferase; thiaminase I; thiamin hydrolase; thiamin pyridinolase; thiaminase; thiamine pyridinolase; thiamin pyridinylase; thiamin:base 2-methyl-4-aminopyrimidine-5-methenyltransferase

Systematic name: thiamine:base 2-methyl-4-aminopyrimidine-5-methenyltransferase

Comments: Various bases and thiol compounds can act instead of pyridine.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, WIT, CAS registry number: 9030-35-7

References:

1. Fujita, A. Thiaminases. Adv. Enzymol. Relat. Subj. Biochem. 15 (1954) 389-421.

2. Kenten, R.H. The partial purification and properties of a thiaminase from bracken [Pteridium aquilinum (L.) Kuhn]. Biochem. J. 67 (1957) 25-33.

3. Wittliff, J.L. and Airth, R.L. The extracellular thiaminase I of Bacillus thiaminolyticus. I. Purification and physicochemical properties. Biochemistry 7 (1968) 736-744. [PMID: 4966932]

EC 2.7.1.148

Common name: 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol kinase

Reaction: ATP + 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol = ADP + 2-phospho-4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol

For diagram click here.

Other name(s): CDP-ME kinase

Systematic name: ATP:4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol 2-phosphotransferase

Comments: The enzyme from Escherichia coli requires Mg²⁺ or Mn²⁺. Forms part of an alternative nonmevalonate pathway for terpenoid biosynthesis (for diagram, click here).

References:

1. Kuzuyama, T., Takagi, M., Kaneda, K., Watanabe, H., Dairi, T. and Seto, H. Studies on the nonmevalonate pathway: conversion of 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol to its 2-phospho derivative by 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol kinase. Tetrahedron Lett. 41 (2000) 2925-2928.

EC 2.7.7.60

Common name: 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase

Reaction: CTP + 2-C-methyl-D-erythritol 4-phosphate = diphosphate + 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol

For diagram click here.

Other name(s): MEP cytidylyltransferase

Systematic name: CTP:2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase

Comments: The enzyme from Escherichia coli requires Mg²⁺ or Mn²⁺. ATP or UTP can replace CTP, but both are less effective. GTP and TTP are not substrates. Forms part of an alternative nonmevalonate pathway for terpenoid biosynthesis (for diagram, click here).

References:

1. Kuzuyama, T., Takagi, M., Kaneda, K., Dairi, T. and Seto, H. Formation of 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol from 2-C-methyl-D-erythritol 4-phosphate by 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase, a new enzyme in the nonmevalonate pathway. Tetrahedron Lett. 41 (2000) 703-706.

[EC 3.2.1.90 Deleted entry: arabinogalactan endo-1,3-β-galactosidase not sufficiently characterised. (EC 3.2.1.90 created 1976, deleted 2001)]

*EC 3.2.1.101

Common name: mannan endo-1,6-β-mannosidase

Reaction: Random hydrolysis of 1,6-α-D-mannosidic linkages in unbranched 1,6-mannans

Other name(s): exo-1,6-β-mannanase; endo-α-16-D-mannanase; endo-1,6-β-mannanase

Systematic name: 1,6-β-D-mannan mannanohydrolase

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number:

References:

1. Nakajima, T., Maitra, S.K. and Ballou, C.E. An endo-α₁ leads to 6-D-mannanase from a soil bacterium. Purification, properties, and mode of action. J. Biol. Chem. 251 (1976) 174-181. [PMID: 811665]

2. Brigance, W.T., Barlowe, C. and Graham, T.R. Organization of the yeast Golgi complex into at least four functionally distinct compartments. Mol. Biol. Cell 11 (2000) 171-182. [PMID: 10637300]

3. Nakajima, T. and Ballou, C.E. Structure of the linkage region between the polysaccharide and protein parts of Saccharomyces cerevisiae mannan. J. Biol. Chem. 249 (1974) 7685-7694. [PMID: 4612041]

EC 3.5.1.88

Common name: peptide deformylase

Reaction: formyl-L-methionyl peptide + H₂O = formate + methionyl peptide

Systematic name: formyl-L-methionyl peptide amidohydrolase

Comments: Requires Fe(II). Also requires at least a dipeptide for an efficient rate of reaction. N-terminal L-methionine is a prerequisite for activity but the enzyme has broad specificity at other positions. Differs in substrate specifity from EC 3.5.1.27 (N-formylmethionylaminoacyl-tRNA deformylase) and EC 3.5.1.31 (formylmethionine demethylase).

References:

1. Adams, J.M. On the release of the formyl group from nascent protein. J. Mol. Biol. 33 (1968) 571-589. [PMID: 4973445]

2. Mazel, D., Pochet, S. and Marliere, P. Genetic characterization of polypeptide deformylase, a distinctive enzyme of eubacterial translation. EMBO J. 13 (1994) 914-923. [PMID: 8112305]

3. Chan, M.K., Gong, W., Rajagopalan, P.T.R., Hao, B., Tsai, C.M. and Pei, D. Crystal structure of the Escherichia coli peptide deformylase. Biochemistry 36 (1997) 13904-13909. [PMID: 9374869]

4. Becker, A., Schlichting, I., Kabsch, W., Schultz, S. and Wagner, A.F.V. Structure of peptide deformylase and identification of the substrate binding site. J. Biol. Chem. 273 (1998) 11413-11416. [PMID: 9565550]

5. Becker, A., Schlichting, I., Kabsch, W., Groche, D., Schultz, S. and Wagner, A.F. Iron center, substrate recognition, and mechanism of peptide deformylase. Nat. Struct. Biol. 5 (1998) 1053-1058. [PMID: 9846875]

6. Rajagopalan, P.T.R., Yu, X.C. and Pei, D. Peptide deformylase: a new type of mononuclear iron protein. J. Am. Chem. Soc. 119 (1997) 12418-12419.

7. Groche, D., Becker, A., Schlichting, I., Kabsch, W., Schultz, S. and Wagner, A.F.V. Isolation and crystallization of functionally competent Escherichia coli peptide deformylase forms containing either iron or nickel in the active site. Biochem. Biophys. Res. Commun. 246 (1998) 342-346. [PMID: 9610360]

8. Rajagopalan, P.T.R., Grimme, S. and Pei, D. Characterization of cobalt(II)-substituted peptide deformylase: function of the metal ion and the catalytic residue Glu-133. Biochemistry 39 (2000) 779-790. [PMID: 10651644]

9. Hu, Y.J., Wei, Y., Zhou, Y., Rajagopalan, P.T.R. and Pei, D. Determination of substrate specificity for peptide deformylase through the screening of a combinatorial peptide library. Biochemistry 38 (1999) 643-650. [PMID: 9888804]

10. Ragasu, S., Mouchet, P., Lazennec, C., Dive, V. and Meinnel, T. Substrate recognition and selectivity of peptide deformylase. Similarities and differences with metzincins and thermolysin. J. Mol. Biol. 289 (1999) 1445-1457. [PMID: 10373378]

11. Giglione, C., Pierre, M. and Meinnel, T. Peptide deformylase as a target for new generation, broad spectrum antimicrobial agents. Mol. Microbiol. 36 (2000) 1197-1205. [PMID: 10931273]

12. Pei, D. Peptide deformylase: a target for novel antibiotics? Emerging Therapeutic Targets 5 (2001) 23-40.

*EC 3.5.2.7

Common name: imidazolonepropionase

Reaction: (S)-3-(5-oxo-4,5-dihydro-3H-imidazol-4-yl)propanoate + H₂O = N-formimidoyl-L-glutamate + H⁺

For diagram click here.

Other name(s): 4(5)-imidazolone-5(4)-propionic acid hydrolase; imidazolone propionic acid hydrolase

Systematic name: 3-(5-oxo-4,5-dihydro-3H-imidazol-4-yl)propanoate amidohydrolase

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9024-91-3

References:

1. Rao, D.R. and Greenberg, D.M. Studies on the enzymic decomposition of urocanic acid. IV. Purification and properties of 4(5)-imidazolone-5(4)-propionic acid hydrolase. J. Biol. Chem. 236 (1961) 1758-1763.

2. Snyder, S.H., Silva, O.L. and Kies, M.W. The mammalian metabolism of L-histidine. IV. Purification and properties of imidazolone propionic acid hydrolase. J. Biol. Chem. 236 (1961) 2996-2998.

*EC 3.5.3.8

Common name: formimidoylglutamase

Reaction: N-formimidoyl-L-glutamate + H₂O = L-glutamate + formamide

Other name(s): formiminoglutamase; N-formiminoglutamate hydrolase; N-formimino-L-glutamate formiminohydrolase

Systematic name: N-formimidoyl-L-glutamate formimidoylhydrolase

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9054-92-6

References:

1. Kaminskas, E., Kimhi, Y. and Magasanik, B. Urocanase and N-formimino-L-glutamate formiminohydrolase of Bacillus subtilis, two enzymes of the histidine degradation pathway. J. Biol. Chem. 245 (1970) 3536-3544. [PMID: 4990470]

2. Lund, P. and Magasanik, B. N-Formimino-L-glutamate formiminohydrolase of Aerobacter aerogenes. J. Biol. Chem. 240 (1965) 4316-4319. [PMID: 5845833]

*EC 4.1.1.39

Common name: ribulose-bisphosphate carboxylase

Reaction: D-ribulose 1,5-bisphosphate + CO₂ = 2 3-phospho-D-glycerate

Other name(s): ribulose bisphosphate carboxylase/oxygenase; rubisco; ribulose diphosphate carboxylase; carboxydismutase; diphosphoribulose carboxylase; D-ribulose 1,5-diphosphate carboxylase; ribulose 1,5-diphosphate carboxylase; ribulose 1,5-bisphosphate carboxylase; D-ribulose-1,5-bisphosphate carboxylase; RuBP carboxylase; ribulose 1,5-bisphosphate carboxylase/oxygenase; ribulose diphosphate carboxylase/oxygenase; ribulose 1,5-diphosphate carboxylase/oxygenase; ribulose diphosphate carboxylase

Systematic name: 3-phospho-D-glycerate carboxy-lyase (dimerizing)

Comments: Will utilize O₂ instead of CO₂, forming 3-phospho-D-glycerate and 2-phosphoglycolate.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, WIT, CAS registry number: 9027-23-0

References:

1. Bowles, G., Ogren, W.L. and Hageman, R.H. Phosphoglycolate production catalyzed by ribulose diphosphate carboxylase. Biochem. Biophys. Res. Commun. 45 (1971) 716-722. [PMID: 4331471]

2. Wishnick, M., Lane, M.D., Scrutton, M.C. and Mildvan, A.S. The presence of tightly bound copper in ribulose diphosphate carboxylase from spinach. J. Biol. Chem. 244 (1969) 5761-5763. [PMID: 4310607]

*EC 4.2.1.49

Common name: urocanate hydratase

Reaction: 3-(5-oxo-4,5-dihydro-3H-imidazol-4-yl)propanoate = urocanate + H₂O

For diagram click here and probable mechanism here.

Other name(s): urocanase

Systematic name: 3-(5-oxo-4,5-dihydro-3H-imidazol-4-yl)propanoate hydro-lyase

Comments: Contains tightly bound NAD⁺.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, WIT, CAS registry number: 9014-58-8

References:

1. Rétey, J. The urocanase story: a novel role of NAD⁺ as electrophile. Arch. Biochem. Biophys. 314 (1994) 1-16. [PMID: 7944380]

2. Hassall, H. and Greenberg, D.M. Urocanase (beef liver). Methods Enzymol. 17B (1971) 84-88.

3. Kaminskas, E., Kimhi, Y. and Magasanik, B. Urocanase and N-formimino-L-glutamate formiminohydrolase of Bacillus subtilis, two enzymes of the histidine degradation pathway. J. Biol. Chem. 245 (1970) 3536-3544. [PMID: 4990470]

4. Swaine, D. The effect of substrate analogues on the activity of cat liver urocanase. Biochim. Biophys. Acta 178 (1969) 609-618. [PMID: 5784906]

EC 4.2.1.104

Common name: cyanate hydratase

Reaction: cyanate (NCO^-) + H₂O = carbamate (H₂N-CO-O^-)

Other names: cyanate lyase; cyanate hydrolase; cyanase; cyanate aminohydrolase

Systematic name: carbamate hydro-lyase

Comment: The enzyme requires bicarbonate as a cofactor. Its mechanism is to catalyse the attack of bicarbonate on cyanate, with elimination of carbon dioxide, thus catalysing hydration of the cyanate to carbamate. The carbamate spontaneously hydrolyses to ammonia and carbon dioxide.

Links to other databases: BRENDA, EXPASY, KEGG, UM-BBD, WIT, CAS registry number: 37289-24-0

References

1. Anderson, P.M. Purification and properties of the inducible enzyme cyanase. Biochemistry 19 (1980) 2882-2888. [PMID: 6994799]

2. Johnson, W.V. and Anderson, P.M. Bicarbonate is a recycling substrate for cyanase. J. Biol. Chem. 262 (1987) 9021-9025. [PMID: 3110153]

3. Taussig, A. The synthesis of the induced enzyme, "cyanase", in E. coli. Biochim. Biophys. Acta 44 (1960) 510-519.

4. Taussig, A. Some properties of the induced enzyme cyanase. Can. J. Biochem. 43 (1965) 1063-1069. [PMID: 5322950]

5. Anderson, P.M., Korte, J.J. and Holcomb, T.A. Reaction of the N-terminal methionine residues in cyanase with diethylpyrocarbonate. Biochemistry 33 (1994) 14121-14125. [PMID: 7947823]

EC 4.2.99.19

Common name: 2-hydroxypropyl-CoM lyase

Reaction: (R)-[or (S)-]2-hydroxypropyl-CoM = (R)-[or (S)-]1,2-epoxypropane + HS-CoM

For diagram click here.

Glossary:
coenzyme M (CoM) = 2-mercaptoethanesulfonate

Other name(s): epoxyalkane:CoM transferase; epoxyalkane:2-mercaptoethanesulfonate transferase

Systematic name: 2-hydroxypropyl-CoM:2-mercaptoethanesulfonate lyase (epoxyalkane-ring-forming)

Comments: Acts on both enantiomers of chiral epoxyalkanes to form the corresponding (R)- and (S)-2-hydroxyalkyl-CoM adducts. The enzyme will function with some other thiols (e.g., 2-mercaptoethanol) as the nucleophile. Uses short-chain epoxyalkanes from C₂ (epoxyethane) to C₆ (1,2-epoxyhexane). This enzyme forms component I of a four-component enzyme system {comprising EC.4.2.99.19 (2-hydroxypropyl-CoM lyase; component I), EC 1.8.1.5 [2-oxopropyl-CoM reductase (carboxylating); component II], EC 1.1.1.268 [2-(R)-hydroxypropyl-CoM dehydrogenase; component III] and EC 1.1.1.269 [2-(S)-hydroxypropyl-CoM dehydrogenase; component IV]} that is involved in epoxyalkane carboxylation in Xanthobacter sp. strain Py2.

References:

1. Allen, J.R., Clark, D.D., Krum, J.G. and Ensign, S.A. A role for coenzyme M (2-mercaptoethanesulfonic acid) in a bacterial pathway of aliphatic epoxide carboxylation. Proc. Natl. Acad. Sci. USA 96 (1999) 8432-8437. [PMID: 10411892]

[EC 4.3.99.1 Transferred entry: now EC 4.2.1.104, cyanate hydratase (EC 4.3.99.1 created 1972 as EC 3.5.5.3, transferred 1990 to EC 4.3.99.1, deleted 2001)]

EC 4.6.1.12

Common name: 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase

Reaction: 2-phospho-4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol = 2-C-methyl-D-erythritol 2,4-cyclodiphosphate + CMP

For diagram click here.

Other name(s): MECDP-synthase

Systematic name: 2-phospho-4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol CMP-lyase (cyclizing)

Comments: The enzyme from Escherichia coli requires Mg²⁺ or Mn²⁺. Forms part of an alternative nonmevalonate pathway for terpenoid biosynthesis (for diagram, click here).

References:

1. Takagi, M., Kuzuyama, T., Kaneda, K., Watanabe, H., Dairi, T. and Seto, H. Studies on the nonmevalonate pathway: Formation of 2-C-methyl-D-erythritol 2,4-cyclodiphosphate from 2-phospho-4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol. Tetrahedron Lett. 41 (2000) 3395-3398.

EC 6.4.1.6

Common name: acetone carboxylase

Reaction: acetone + CO₂ + ATP + 2 H₂O = acetoacetate + AMP + 2 phosphate

Systematic name: acetone:carbon-dioxide ligase (AMP-forming)

Comments: Requires Mg²⁺ and ATP. The enzyme from Xanthobacter sp. strain Py2 also carboxylates butan-2-one to 3-oxopentanoate.

References:

1. Sluis, M.K. and Ensign, S.A. Purification and characterization of acetone carboxylase from Xanthobacter strain Py2. Proc. Natl. Acad. Sci. USA 94 (1997) 8456-8461. [PMID: 9237998]