Enzyme Nomenclature

Continued from EC 1.14.13.1 to EC 1.14.13.50

EC 1.14.13 (Continued)

See separate file for EC 1.14.13.1 to EC 1.14.13.50
EC 1.14.13.101 to EC 1.14.13.150
EC 1.14.13.151 to EC 1.14.13.238

Contents

EC 1.14.13.51 6-oxocineole dehydrogenase
EC 1.14.13.52 isoflavone 3'-hydroxylase
EC 1.14.13.53 4'-methoxyisoflavone 2'-hydroxylase
EC 1.14.13.54 ketosteroid monooxygenase
EC 1.14.13.55 protopine 6-monooxygenase
EC 1.14.13.56 dihydrosanguinarine 10-monooxygenase
EC 1.14.13.57 dihydrochelirubine 12-monooxygenase
EC 1.14.13.58 benzoyl-CoA 3-monooxygenase
EC 1.14.13.59 L-lysine 6-monooxygenase (NADPH)
EC 1.14.13.60 27-hydroxycholesterol 7α-monooxygenase
EC 1.14.13.60 transferred now EC 1.14.13.100
EC 1.14.13.61 2-hydroxyquinoline 8-monooxygenase
EC 1.14.13.62 4-hydroxyquinoline 3-monooxygenase
EC 1.14.13.63 3-hydroxyphenylacetate 6-hydroxylase
EC 1.14.13.64 4-hydroxybenzoate 1-hydroxylase
EC 1.14.13.65 deleted
EC 1.14.13.66 2-hydroxycyclohexanone 2-monooxygenase
EC 1.14.13.67 quinine 3-monooxygenase
EC 1.14.13.68 now EC 1.14.14.37
EC 1.14.13.69 alkene monooxygenase
EC 1.14.13.70 sterol 14α-demethylase
EC 1.14.13.71 N-methylcoclaurine 3'-monooxygenase
EC 1.14.13.72 transferred now EC 1.14.18.9
EC 1.14.13.73 tabersonine 16-hydroxylase
EC 1.14.13.74 7-deoxyloganin 7-hydroxylase
EC 1.14.13.75 vinorine hydroxylase
EC 1.14.13.76 taxane 10β-hydroxylase
EC 1.14.13.77 taxane 13α-hydroxylase
EC 1.14.13.78 ent-kaurene oxidase
EC 1.14.13.79 ent-kaurenoic acid oxidase
EC 1.14.13.80 transferred now EC 1.14.14.53
EC 1.14.13.81 magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase
EC 1.14.13.82 vanillate monooxygenase
EC 1.14.13.83 precorrin-3B synthase
EC 1.14.13.84 4-hydroxyacetophenone monooxygenase
EC 1.14.13.85 glyceollin synthase
EC 1.14.13.86 deleted
EC 1.14.13.87 licodione synthase
EC 1.14.13.88 flavonoid 3',5'-hydroxylase
EC 1.14.13.89 isoflavone 2'-hydroxylase
EC 1.14.13.90 now EC 1.14.15.21
EC 1.14.13.91 deoxysarpagine hydroxylase
EC 1.14.13.92 phenylacetone monooxygenase
EC 1.14.13.93 (+)-abscisic acid 8'-hydroxylase
EC 1.14.13.94 lithocholate 6β-hydroxylase
EC 1.14.13.95 now EC 1.14.18.8
EC 1.14.13.96 5β-cholestane-3α,7α-diol 12α-hydroxylase
EC 1.14.13.97 taurochenodeoxycholate 6α-hydroxylase
EC 1.14.13.98 now EC 1.14.14.25
EC 1.14.13.99 now EC 1.14.14.26
EC 1.14.13.100 now EC 1.14.14.29

See the following files for:
EC 1.14.13.101 to EC 1.14.13.150
EC 1.14.13.151 to EC 1.14.13.238

EC 1.14.13.51

Accepted name: 6-oxocineole dehydrogenase

Reaction: 6-oxocineole + NADPH + H+ + O2 = 1,6,6-trimethyl-2,7-dioxabicyclo[3.2.2]nonan-3-one + NADP+ + H2O

For diagram of reaction click here.

Other name(s): 6-oxocineole oxygenase

Systematic name: 6-oxocineole,NADPH:oxygen oxidoreductase

Comments: The product undergoes non-enzymic cleavage and subsequent ring closure to form the lactone 4,5-dihydro-5,5-dimethyl-4-(3-oxobutyl)furan-2(3H)-one.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 122933-80-6

References:

1. Williams, D.R., Trudgill, P.W. and Taylor, D.G. Metabolism of 1,8-cineole by a Rhodococcus species - ring cleavage reactions. J. Gen. Microbiol. 135 (1989) 1957-1967.

[EC 1.14.13.51 created 1992]

EC 1.14.13.52

Accepted name: isoflavone 3'-hydroxylase

Reaction: formononetin + NADPH + H+ + O2 = calycosin + NADP+ + H2O

For diagram click here.

Other name(s): isoflavone 3'-monooxygenase

Systematic name: formononetin,NADPH:oxygen oxidoreductase (3'-hydroxylating)

Comments: A heme-thiolate protein (P-450). Also acts on biochanin A and other isoflavones with a 4'-methoxy group. Involved in the biosynthesis of the pterocarpin phytoalexins medicarpin and maackiain.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 110183-50-1

References:

1. Hinderer, W., Flentje, U. and Barz, W. Microsomal isoflavone 2'-hydroxylases and 3'-hydroxylases from chickpea (Cicer arietinum L) cell-suspensions induced for pterocarpan phytoalexin formation. FEBS Lett. 214 (1987) 101-106.

[EC 1.14.13.52 created 1992]

EC 1.14.13.53

Accepted name: 4'-methoxyisoflavone 2'-hydroxylase

Reaction: formononetin + NADPH + H+ + O2 = 2'-hydroxyformononetin + NADP+ + H2O

For diagram click here.

Other name(s): isoflavone 2'-monooxygenase (ambiguous); isoflavone 2'-hydroxylase (ambiguous)

Systematic name: formononetin,NADPH:oxygen oxidoreductase (2'-hydroxylating)

Comments: A heme-thiolate protein (P-450). Acts on isoflavones with a 4'-methoxy group, such as formononetin and biochanin A. Involved in the biosynthesis of the pterocarpin phytoalexins medicarpin and maackiain. EC 1.14.13.89, isoflavone 2'-hydroxylase, is less specific and acts on other isoflavones as well as 4'-methoxyisoflavones.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 110183-49-8

References:

1. Hinderer, W., Flentje, U. and Barz, W. Microsomal isoflavone 2'-hydroxylases and 3'-hydroxylases from chickpea (Cicer arietinum L) cell-suspensions induced for pterocarpan phytoalexin formation. FEBS Lett. 214 (1987) 101-106.

[EC 1.14.13.53 created 1992, modified 2005]

EC 1.14.13.54

Accepted name: ketosteroid monooxygenase

Reaction: a ketosteroid + NADPH + H+ + O2 = a steroid ester/lactone + NADP+ + H2O (general reaction)
(1) progesterone + NADPH + H+ + O2 = testosterone acetate + NADP+ + H2O
(2) androstenedione + NADPH + H+ + O2 = testololactone + NADP+ + H2O
(3) 17α-hydroxyprogesterone + NADPH + H+ + O2 = androstenedione + acetate + NADP+ + H2O

Glossary: progesterone = pregn-4-ene-3,20-dione
testosterone acetate = 3-oxoandrost-4-en-17β-yl acetate
androstenedione = androst-4-ene-3,17-dione
testololactone = 3-oxo-13,17-secoandrost-4-eno-17,13α-lactone
17α-hydroxyprogesterone = 17α-hydroxypregn-4-ene-3,20-dione

Other name(s): steroid-ketone monooxygenase; progesterone, NADPH2:oxygen oxidoreductase (20-hydroxylating, ester-producing); 17α-hydroxyprogesterone, NADPH2:oxygen oxidoreductase (20-hydroxylating, side-chain cleaving); androstenedione, NADPH2:oxygen oxidoreductase (17-hydroxylating, lactonizing)

Systematic name: ketosteroid,NADPH:oxygen oxidoreductase (20-hydroxylating, ester-producing/20-hydroxylating, side-chain cleaving/17-hydroxylating, lactonizing)

Comments: A single FAD-containing enzyme catalyses three types of monooxygenase (Baeyer-Villiger oxidation) reaction. The oxidative esterification of a number of derivatives of progesterone to produce the corresponding 17α-hydroxysteroid 17-acetate ester, such as testosterone acetate, is shown in Reaction (1). The oxidative lactonization of a number of derivatives of androstenedione to produce the 13,17-secoandrosteno-17,13α-lactone, such as testololactone, is shown in Reaction (2). The oxidative cleavage of the 17β-side-chain of 17α-hydroxyprogesterone to produce androstenedione and acetate is shown in Reaction (3). Reaction (1) is also catalysed by EC 1.14.99.4 (progesterone monooxygenase), and Reactions (2) and (3) correspond to that catalysed by EC 1.14.99.12 (androst-4-ene-3,17-dione monooxygenase). The possibility that a single enzyme is responsible for the reactions ascribed to EC 1.14.99.4 and EC 1.14.99.12 in other tissues cannot be excluded.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9044-53-5

References:

1. Katagiri, M. and Itagaki, E. A steroid ketone monooxygenase from Cylindrocarpon radicicola. in Chemistry and Biochemistry of Flavoenzymes, (Müller, F., ed.) (1991) pp. 102-108, CRC Press, Florida.

2. Itagaki, E. Studies on a steroid monooxygenase from Cylindrocarpon radicicola ATCC 11011. Purification and characterization. J. Biochem. (Tokyo) 99 (1986) 815-824. [PMID: 3486863]

3. Itagaki, E. Studies on a steroid monooxygenase from Cylindrocarpon radicicola ATCC11011. Oxygenative lactonization of androstenedione to testololactone. J. Biochem. (Tokyo) 99 (1986) 825-832. [PMID: 3486864]

[EC 1.14.13.54 created 1999]

EC 1.14.13.55

Accepted name: protopine 6-monooxygenase

Reaction: protopine + NADPH + H+ + O2 = 6-hydroxyprotopine + NADP+ + H2O

For diagram click here.

Other name(s): protopine 6-hydroxylase

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

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

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 128561-60-4

References:

1. Tanahashi, T. and Zenk, M.H. Elicitor induction and characterization of microsomal protopine-6-hydroxylase, the central enzyme in benzophenanthridine alkaloid biosynthesis. Phytochemistry 29 (1990) 1113-1122.

[EC 1.14.13.55 created 1999]

EC 1.14.13.56

Accepted name: dihydrosanguinarine 10-monooxygenase

Reaction: dihydrosanguinarine + NADPH + H+ + O2 = 10-hydroxydihydrosanguinarine + NADP+ + H2O

For diagram click here.

Other name(s): dihydrosanguinarine 10-hydroxylase

Systematic name: dihydrosanguinarine,NADPH:oxygen oxidoreductase (10-hydroxylating)

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

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 144388-41-0

References:

1. De-Eknamkul, W., Tanahashi, T. and Zenk, M.H. Enzymic 10-hydroxylation and 10-O-methylation of dihydrosanguinarine in dihydrochelirubine formation by Eschscholtzia. Phytochemistry 31 (1992) 2713-2717.

[EC 1.14.13.56 created 1999]

EC 1.14.13.57

Accepted name: dihydrochelirubine 12-monooxygenase

Reaction:dihydrochelirubine + NADPH + H+ + O2 = 12-hydroxydihydrochelirubine + NADP+ + H2O

For diagram click here.

Other name(s): dihydrochelirubine 12-hydroxylase

Systematic name: dihydrochelirubine,NADPH:oxygen oxidoreductase (12-hydroxylating)

Comments: a heme-thiolate protein (P-450)

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 158736-41-5

References:

1. Kammerer, L., De-Eknamkul, W. and Zenk, M.H. Enzymic 12-hydroxylation and 12-O-methylation of dihydrochelirubine in dihydromacarpine formation by Thalictrum bulgaricum. Phytochemistry 36 (1994) 1409-1416.

[EC 1.14.13.57 created 1999]

EC 1.14.13.58

Accepted name: benzoyl-CoA 3-monooxygenase

Reaction: benzoyl-CoA + NADPH + H+ + O2 = 3-hydroxybenzoyl-CoA + NADP+ + H2O

Other name(s): benzoyl-CoA 3-hydroxylase

Systematic name: benzoyl-CoA,NADPH:oxygen oxidoreductase (3-hydroxylating)

Comments: the enzyme from the denitrifying bacterium Pseudomonas KB740 catalyses a flavin-requiring reaction (FAD or FMN). Benzoate is not a substrate.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 151616-61-4

References:

1. Niemetz, R., Altenschmidt, U., Herrmann, H. and Fuchs, G. Benzoyl-coenzyme-A 3-monooxygenase, a flavin-dependent hydroxylase. Purification, some properties and its role in aerobic benzoate oxidation via gentisate in a denitrifying bacterium. Eur. J. Biochem. 227 (1995) 161-168. [PMID: 7851381]

[EC 1.14.13.58 created 1999]

EC 1.14.13.59

Accepted name: L-lysine N6-monooxygenase (NADPH)

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

For diagram of reaction click here

Other name(s): lysine N6-hydroxylase; L-lysine 6-monooxygenase (NADPH) (ambiguous)

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

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

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, 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 1.14.13.59 created 1999, modified 2001, modified 2012]

[EC 1.14.13.60 Transferred entry: 27-hydroxycholesterol 7α-monooxygenase. Now included with EC 1.14.13.100, 25/26-hydroxycholesterol 7α-hydroxylase (EC 1.14.13.60 created 1999, deleted 2013)]

EC 1.14.13.60

Accepted name: 27-hydroxycholesterol 7α-monooxygenase

Reaction: 27-hydroxycholesterol + NADPH + H+ + O2 = 7α,27-dihydroxycholesterol + NADP+ + H2O

For diagram click here.

Other name(s): 27-hydroxycholesterol 7α-hydroxylase

Systematic name: 27-hydroxycholesterol,NADPH:oxygen oxidoreductase (7α-hydroxylating)

Comments: a heme-thiolate protein (P-450). The enzyme from mammalian liver differs from cholesterol 7α-monooxygenase (EC 1.14.13.17) in having no activity towards cholesterol.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 149316-80-3

References:

1. Kumiko, O.M., Budai, K. and Javitt, N.B. Cholesterol and 27-hydroxycholesterol 7α-hydroxylation: evidence for two different enzymes. J. Lipid Res. 34 (1993) 581-588.

[EC 1.14.13.60 created 1999]

EC 1.14.13.61

Accepted name: 2-hydroxyquinoline 8-monooxygenase

Reaction: quinolin-2-ol + NADH + H+ + O2 = quinolin-2,8-diol + NAD+ + H2O

Other name(s): 2-oxo-1,2-dihydroquinoline 8-monooxygenase

Systematic name: quinolin-2(1H)-one, NADH:oxygen oxidoreductase (8-oxygenating)

Comments: requires iron. Quinolin-2-ol exists largely as the quinolin-2(1H)-one tautomer.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 166799-89-9

References:

1. Rosche, B., Tshisuaka, B., Fetzner, S. and Lingens, F. 2-Oxo-1,2-dihydroquinoline 8-monooxygenase, a two-component enzyme system from Pseudomonas putida 86. J. Biol. Chem. 270 (1995) 17836-17842. [PMID: 7629085]

[EC 1.14.13.61 created 1999]

EC 1.14.13.62

Accepted name: 4-hydroxyquinoline 3-monooxygenase

Reaction: quinolin-4-ol + NADH + H+ + O2 = quinolin-3,4-diol + NAD+ + H2O

Other name(s): quinolin-4(1H)-one 3-monooxygenase

Systematic name: quinolin-4(1H)-one,NADH:oxygen oxidoreductase (3-oxygenating)

Comments: quinolin-4-ol exists largely as the quinolin-4(1H)-one tautomer.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 144378-37-0

References:

1. Block, D.W. and Lingens, F. Microbial metabolism of quinoline and related compounds. XIV. Purification and properties of 1H-3-hydroxy-4-oxoquinoline oxygenase, a new estradiol cleavage enzyme from Pseudomonas putida strain 33/1. Biol. Chem. Hoppe Seyler 373 (1992) 249-254. [PMID: 1627263]

[EC 1.14.13.62 created 1999]

EC 1.14.13.63

Accepted name: 3-hydroxyphenylacetate 6-hydroxylase

Reaction: 3-hydroxyphenylacetate + NAD(P)H + H+ + O2 = 2,5-dihydroxyphenylacetate + NAD(P)+ + H2O

For diagram of reaction click here.

Glossary: homogentisate = 2,5-dihydroxyphenylacetate

Other name(s): 3-hydroxyphenylacetate 6-monooxygenase

Systematic name: 3-hydroxyphenylacetate,NAD(P)H:oxygen oxidoreductase (6-hydroxylating)

Comments: 3-hydroxyphenylacetate 6-hydroxylase from Flavobacterium sp. is highly specific for 3-hydroxyphenylacetate and uses NADH and NADPH as electron donors with similar efficiency.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 114705-01-0

References:

1. van Berkel, W.H.J. and van den Tweel, W.J.J. Purification and characterisation of 3-hydroxyphenylacetate 6-hydroxylase: a novel FAD-dependent monooxygenase from a Flavobacterium sp. Eur. J. Biochem. 201 (1991) 585-592. [PMID: 1935954]

[EC 1.14.13.63 created 1999]

EC 1.14.13.64

Accepted name: 4-hydroxybenzoate 1-hydroxylase

Reaction: 4-hydroxybenzoate + NAD(P)H + 2 H+ + O2 = hydroquinone + NAD(P)+ + H2O + CO2

Other name(s): 4-hydroxybenzoate 1-monooxygenase

Systematic name: 4-hydroxybenzoate,NAD(P)H:oxygen oxidoreductase (1-hydroxylating, decarboxylating)

Comments: requires FAD. The enzyme from Candida parapsilosis is specific for 4-hydroxybenzoate derivatives and prefers NADH to NADPH as electron donor.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, UM-BBD , CAS registry number: 134214-78-1

References:

1. van Berkel, W.J.H., Eppink, M.H.M., Middelhoven, W.J., Vervoort, J. and Rietjens, I.M.C.M. Catabolism of 4-hydroxybenzoate in Candida parapsilosis proceeds through initial oxidative decarboxylation by a FAD-dependent 4-hydroxybenzoate 1-hydroxylase. FEMS Microbiol. Lett. 121 (1994) 207-216. [PMID: 7926672]

[EC 1.14.13.64 created 1999]

[EC 1.14.13.65 Deleted entry: 2-hydroxyquinoline 8-monooxygenase (EC 1.14.13.65 created 1999, deleted 2006)]

EC 1.14.13.66

Accepted name: 2-hydroxycyclohexanone 2-monooxygenase

Reaction: 2-hydroxycyclohexan-1-one + NADPH + H+ + O2 = 6-hydroxyhexan-6-olide + NADP+ + H2O

Systematic name: 2-hydroxycyclohexan-1-one,NADPH:oxygen 2-oxidoreductase (1,2-lactonizing)

Comment: the product decomposes spontaneously to 6-oxohexanoic acid (adipic semialdehyde).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 62628-31-3

References

1. Davey, J.F. and Trudgill, P.W. The metabolism of trans-cyclohexan-1,2-diol by an Acinetobacter species. Eur. J. Biochem. 74 (1977) 115-127. [PMID: 856571]

[EC 1.14.13.66 created 1978 as EC 1.14.12.6, transferred 1999 to EC 1.14.13.66]

EC 1.14.13.67

Accepted name: quinine 3-monooxygenase

Reaction: quinine + NADPH + H+ + O2 = 3-hydroxyquinine + NADP+ + H2O

Glossary entries:
Quinine: a quinoline alkaloid

Other name(s): quinine 3-hydroxylase

Systematic name: quinine,NADPH:oxygen oxidoreductase

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

References:

1. Relling, M.V., Evans, R., Dass, C., Desiderio, D.M. and Nemec, J. Human cytochrome P450 metabolism of teniposide and etoposide. J. Pharmacol. Exp. Ther. 261 (1992) 491-496. [PMID: 1578365]

2. Zhang, H., Coville, P.F., Walker, R.J., Miners, J.O., Birkett, D.J. and Wanwimolruk, S. Evidence for involvement of human CYP3A in the 3-hydroxylation of quinine. Br. J. Clin. Pharmacol. 43 (1997) 245-252. [PMID: 9088578]

3. Zhao, X.-J., Kawashiro, T. and Ishizaki, T. Mutual inhibition between quinine and etoposide by human liver microsomes. Evidence for cytochrome P4503A4 involvement in their major metabolic pathways. Drug Metab. Dispos. 26 (1998) 188-191. [PMID: 9456308]

4. Zhao, X.-J., Yokoyama, H., Chiba, K., Wanwimolruk, S. and Ishizaki, T. Identification of human cytochrome P450 isoforms involved in the 3-hydroxylation of quinine by human liver microsomes and nine recombinant human cytochromes P450. J. Pharmacol. Exp. Ther. 279 (1996) 1327-1334. [PMID: 8968357]

[EC 1.14.13.67 created 2000]

[EC 1.14.13.68 Transferred entry: 4-hydroxyphenylacetaldehyde oxime monooxygenase, now EC 1.14.14.37, 4-hydroxyphenylacetaldehyde oxime monooxygenase (EC 1.14.13.68 created 2000, modified 2005, deleted 2016)]

EC 1.14.13.69

Accepted 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: This bacterial binuclear non-heme iron enzyme is a multicomponent enzyme complex comprising an oxygenase, a reductase, and a Rieske-type ferredoxin. The enzyme from the bacterium Xanthobacter sp. strain Py2 contains an additional small protein of unknown function that is essential for activity. In general, the enzyme oxygenates C2 to C6 aliphatic alkenes, although enzymes from different organisms show different substrate range. With propene as substrate, the stereospecificity of the epoxypropane formed is 95% (R) and 5% (S).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, UM-BBD, CAS registry number: 63439-50-9

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 1.14.13.69 created 2001]

EC 1.14.13.70

Accepted name: sterol 14α-demethylase

Reaction: a 14α-methylsteroid + 3 O2 + 3 NADPH + 3 H+ = a Δ14-steroid + formate + 3 NADP+ + 4 H2O

For diagram of reaction 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 14-demethylase

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

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

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 60063-87-8

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 (P45014DM) 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 1.14.13.70 created 2001, modified 2013]

EC 1.14.13.71

Accepted 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.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 202420-37-9

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 1.14.13.71 created 2001]

[EC 1.14.13.72 Transferred entry: methylsterol monooxygenase. Now classified as EC 1.14.18.9, methylsterol monooxygenase (EC 1.14.13.72 created 1972 as EC 1.14.99.16, transferred 2002 to EC 1.14.13.72, deleted 2017)]

EC 1.14.13.73

Accepted name: tabersonine 16-hydroxylase

Reaction: tabersonine + NADPH + H+ + O2 = 16-hydroxytabersonine + NADP+ + H2O

For diagram click here.

Other name(s): tabersonine-11-hydroxylase; T11H

Systematic name: tabersonine,NADPH:oxygen oxidoreductase (16-hydroxylating)

Comments: A heme-thiolate protein (P-450).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 250378-34-8

References:

1. St-Pierre, B. and De Luca, V. A cytochrome-P-450 monooxygenase catalyzes the first step in the conversion of tabersonine to vindoline in Catharanthus-roseus. Plant Physiol. 109 (1995) 131-139.

[EC 1.14.13.73 created 2002]

EC 1.14.13.74

Accepted name: 7-deoxyloganin 7-hydroxylase

Reaction: 7-deoxyloganin + NADPH + H+ + O2 = loganin + NADP+ + H2O

For diagram click here.

Systematic name: 7-deoxyloganin,NADPH:oxygen oxidoreductase (7α-hydroxylating)

Comments: A heme-thiolate protein (P-450).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 335305-40-3

References:

1. Katano, N., Yamamoto, H., Iio, R. and Inoue, K. 7-Deoxyloganin 7-hydroxylase in Lonicera japonica cell cultures Phytochemistry 58 (2001) 53-58. [PMID: 11524113]

[EC 1.14.13.74 created 2002]

EC 1.14.13.75

Accepted name: vinorine hydroxylase

Reaction: vinorine + NADPH + H+ + O2 = vomilenine + NADP+ + H2O

For diagram click here.

Systematic name: vinorine,NADPH:oxygen oxidoreductase (21α-hydroxylating)

Comments: A heme-thiolate protein (P-450). Forms a stage in the biosynthesis of the indole alkaloid ajmaline.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 162875-03-8

References:

1. Falkenhagen, H. and Stöckligt, J. Enzymatic biosynthesis of vomilenine, a key intermediate of the ajmaline pathway, catalysed by a novel cytochrome P-450-dependent enzyme from plant cell cultures of Rauwolfia serpentina. Z. Naturforsch. C: Biosci. 50 (1995) 45-53.

[EC 1.14.13.75 created 2002]

EC 1.14.13.76

Accepted name: taxane 10β-hydroxylase

Reaction: taxa-4(20),11-dien-5α-yl acetate + NADPH + H+ + O2 = 10β-hydroxytaxa-4(20),11-dien-5α-yl acetate+ NADP+ + H2O

For diagram click here.

Systematic name: taxa-4(20),11-dien-5α-yl acetate,NADPH:oxygen oxidoreductase (10β-hydroxylating)

Comments: This microsomal cytochrome-P450-dependent enzyme is involved in the biosynthesis of the diterpenoid antineoplastic drug taxol (paclitaxel).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 337514-75-7

References:

1. Wheeler, A.L., Long, R.M., Ketchum, R.E., Rithner, C.D., Williams, R.M. and Croteau, R. Taxol biosynthesis: differential transformations of taxadien-5α-ol and its acetate ester by cytochrome P450 hydroxylases from Taxus suspension cells. Arch. Biochem. Biophys. 390 (2001) 265-78. [PMID: 11396929]

2. Jennewein, S., Rithner, C.D., Williams, R.M. and Croteau, R.B. Taxol biosynthesis: taxane 13 α-hydroxylase is a cytochrome P450-dependent monooxygenase. Proc. Natl. Acad. Sci. U S A 98 (2001) 13595-135600. [PMID: 11707604]

3. Schoendorf, A., Rithner, C.D., Williams, R.M. and Croteau, R.B. Molecular cloning of a cytochrome P450 taxane 10β-hydroxylase cDNA from Taxus and functional expression in yeast. Proc. Natl. Acad. Sci. USA 98 (2001) 1501-1506. [PMID: 11171980]

[EC 1.14.13.76 created 2002]

EC 1.14.13.77

Accepted name: taxane 13α-hydroxylase

Reaction: taxa-4(20),11-dien-5α-ol + NADPH + H+ + O2 = taxa-4(20),11-dien-5α,13α-diol + NADP+ + H2O

For diagram click here.

Systematic name: taxa-4(20),11-dien-5α-ol,NADPH:oxygen oxidoreductase (13α-hydroxylating)

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 399030-58-1

References:

1. Wheeler, A.L., Long, R.M., Ketchum, R.E., Rithner, C.D., Williams, R.M. and Croteau, R. Taxol biosynthesis: differential transformations of taxadien-5α-ol and its acetate ester by cytochrome P450 hydroxylases from Taxus suspension cells. Arch. Biochem. Biophys. 390 (2001) 265-78. [PMID: 11396929]

2. Jennewein, S., Rithner, C.D., Williams, R.M. and Croteau, R.B. Taxol biosynthesis: taxane 13 α-hydroxylase is a cytochrome P450-dependent monooxygenase. Proc. Natl. Acad. Sci. U S A 98 (2001) 13595-135600. [PMID: 11707604]

[EC 1.14.13.77 created 2002]

EC 1.14.13.78

Accepted name: ent-kaurene oxidase

Reaction: ent-kaur-16-ene + 3 NADPH + 3 H+ + 3 O2 = ent-kaur-16-en-19-oate + 3 NADP+ + 4 H2O (overall reaction)
(1a) ent-kaur-16-ene + NADPH + H+ + O2 = ent-kaur-16-en-19-ol + NADP+ + H2O
(1b) ent-kaur-16-en-19-ol + NADPH + H+ + O2 = ent-kaur-16-en-19-al + NADP+ + 2 H2O
(1c) ent-kaur-16-en-19-al + NADPH + O2 = ent-kaur-16-en-19-oate + NADP+ + H2O

For diagram click here.

Systematic name: ent-kaur-16-ene,NADPH:oxygen oxidoreductase (hydroxylating)

Comments: Requires cytochrome P450. Catalyses three sucessive oxidations of the 4-methyl group of ent-kaurene giving kaurenoic acid.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 149565-67-3

References:

1. Ashman, P.J., Mackenzie, A. and Bramley, P.M. Characterization of ent-kaurene oxidase activity from Gibberella fujikuroi. Biochim. Biophys. Acta 1036 (1990) 151-157. [PMID: 2223832]

2. Archer, C., Ashman, P.J., Hedden, P., Bowyer, J.R. and Bramley, P.M. Purification of ent-kaurene oxidase from Gibberella fujikuroi and Cucurbita maxima. Biochem. Soc. Trans. 20 (1992) 218S only. [PMID: 1397591]

3. Helliwell, C.A., Poole, A., Peacock, W.J. and Dennis, E.S. Arabidopsis ent-kaurene oxidase catalyzes three steps of gibberellin biosynthesis. Plant Physiol. 119 (1999) 507-510. [PMID: 9952446]

[EC 1.14.13.78 created 2002]

EC 1.14.13.79

Accepted name: ent-kaurenoic acid oxidase

Reaction: ent-kaur-16-en-19-oate + 3 NADPH + 3 H+ + 3 O2 = gibberellin A12 + 3 NADP+ + 4 H2O (overall reaction)
(1a) ent-kaur-16-en-19-oate + NADPH + H+ + O2 = ent-7α-hydroxykaur-16-en-19-oate + NADP+ + H2O

(1b) ent-7α-hydroxykaur-16-en-19-oate + NADPH + H+ + O2 = gibberellin A12 aldehyde + NADP+ + 2 H2O

(1c) gibberellin A12 aldehyde + NADPH + O2 = gibberellin A12 + NADP+ + H2O

For diagram click here.

Systematic name: ent-kaur-16-en-19-oate,NADPH:oxygen oxidoreductase (hydroxylating)

Comments: Requires cytochrome P450. Catalyses three sucessive oxidations of ent-kaurenoic acid. The second step includes a ring-B contraction giving the gibbane skeleton. In pumpkin (Cucurbita maxima) ent-6α,7α-dihydroxykaur-16-en-19-oate is also formed.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 337507-95-6

References:

1. Helliwell, C.A., Chandler, P.M., Poole, A., Dennis, E.S. and Peacock, W.J. The CYP88A cytochrome P450, ent-kaurenoic acid oxidase, catalyzes three steps of the gibberellin biosynthesis pathway. Proc. Natl. Acad. Sci. USA 98 (2001) 2065-2070. [PMID: 11172076]

[EC 1.14.13.79 created 2002]

[EC 1.14.13.80 Transferred entry: (R)-limonene 6-monooxygenase. Now classified as EC 1.14.14.53, (R)-limonene 6-monooxygenase (EC 1.14.13.80 created 2003, deleted 2017)]

EC 1.14.13.81

Accepted name: magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase

Reaction: magnesium-protoporphyrin IX 13-monomethyl ester + 3 NADPH + 3 H+ + 3 O2 = 3,8-divinyl protochlorophyllide a + 3 NADP+ + 5 H2O (overall reaction)
(1a) magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 = 131-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester + NADP+ + H2O
(1b) 131-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 = 131-oxo-magnesium-protoporphyrin IX 13-monomethyl ester + NADP+ + 2 H2O
(1c) 131-oxo-magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 = 3,8-divinyl protochlorophyllide a + NADP+ + 2 H2O

For diagram of reaction click here.

Other name(s): Mg-protoporphyrin IX monomethyl ester (oxidative) cyclase

Systematic name: magnesium-protoporphyrin-IX 13-monomethyl ester,NADPH:oxygen oxidoreductase (hydroxylating)

Comments: Requires Fe(II) for activity. The enzyme participates in the biosynthesis of chlorophyllide a in aerobic organisms. The same transformation is achieved in anaerobic organisms by EC 1.21.98.3, anaerobic magnesium-protoporphyrin IX monomethyl ester cyclase. Some facultative phototrophic bacteria, such as Rubrivivax gelatinosus, possess both enzymes.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 92353-62-3

References:

1. Walker, C.J., Mansfield, K.E., Rezzano, I.N., Hanamoto, C.M., Smith, K.M. and Castelfranco, P.A. The magnesium-protoporphyrin IX (oxidative) cyclase system. Studies on the mechanism and specificity of the reaction sequence. Biochem. J. 255 (1988) 685-692. [PMID: 3202840]

2. Bollivar, D.W. and Beale, S.I. The chlorophyll biosynthetic enzyme Mg-protoporphyrin IX monomethyl ester (oxidative) cyclase (characterization and partial purification from Chlamydomonas reinhardtii and Synechocystis sp. PCC 6803). Plant Physiol. 112 (1996) 105-114. [PMID: 12226378]

3. Pinta, V., Picaud, M., Reiss-Husson, F. and Astier, C. Rubrivivax gelatinosus acsF (previously orf358) codes for a conserved, putative binuclear-iron-cluster-containing protein involved in aerobic oxidative cyclization of Mg-protoporphyrin IX monomethylester. J. Bacteriol. 184 (2002) 746-753. [PMID: 11790744]

4. Tottey, S., Block, M.A., Allen, M., Westergren, T., Albrieux, C., Scheller, H.V., Merchant, S. and Jensen, P.E. Arabidopsis CHL27, located in both envelope and thylakoid membranes, is required for the synthesis of protochlorophyllide. Proc. Natl. Acad. Sci. USA 100 (2003) 16119-16124. [PMID: 14673103]

[EC 1.14.13.81 created 2003, modified 2017]

EC 1.14.13.82

Accepted name: vanillate monooxygenase

Reaction: vanillate + O2 + NADH + H+ = 3,4-dihydroxybenzoate + NAD+ + H2O + formaldehyde

For diagram of reaction click here

Glossary entries: vanillate = 4-hydroxy-3-methoxybenzoate

Other name(s): 4-hydroxy-3-methoxybenzoate demethylase; vanillate demethylase

Systematic name: vanillate:oxygen oxidoreductase (demethylating)

Comments: Forms part of the vanillin degradation pathway in Arthrobacter sp.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, UM-BBD, CAS registry number: 39307-11-4

References:

1. Brunel, F. and Davison, J. Cloning and sequencing of Pseudomonas genes encoding vanillate demethylase. J. Bacteriol. 170 (1988) 4924-4930. [PMID: 3170489]

2. Priefert, H., Rabenhorst, J. and Steinbuchel, A. Molecular characterization of genes of Pseudomonas sp. strain HR199 involved in bioconversion of vanillin to protocatechuate. J. Bacteriol. 179 (1997) 2595-2607. [PMID: 9098058]

[EC 1.14.13.82 created 2000 as EC 1.2.3.12, transferred 2003 to EC 1.14.13.82]

EC 1.14.13.83

Accepted name: precorrin-3B synthase

Reaction: precorrin-3A + NADH + H+ + O2 = precorrin-3B + NAD+ + H2O

For diagram click here and mechanism here.

Other name(s): precorrin-3X synthase; CobG

Systematic name: precorrin-3A,NADH:oxygen oxidoreductase (20-hydroxylating)

Comments: An iron-sulfur protein. An oxygen atom from dioxygen is incorporated into the macrocycle at C-20. In the aerobic cobalamin biosythesis pathway, four enzymes are involved in the conversion of precorrin-3A to precorrin-6A. The first of the four steps is carried out by EC 1.14.13.83, precorrin-3B synthase (CobG), yielding precorrin-3B as the product. This is followed by three methylation reactions, which introduce a methyl group at C-17 (CobJ; EC 2.1.1.131), C-11 (CobM; EC 2.1.1.133) and C-1 (CobF; EC 2.1.1.152) of the macrocycle, giving rise to precorrin-4, precorrin-5 and precorrin-6A, respectively.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 152787-63-8

References:

1. Debussche, L., Thibaut, D., Cameron, B., Crouzet, J. and Blanche, F. Biosynthesis of the corrin macrocycle of coenzyme B12 in Pseudomonas denitrificans. J. Bacteriol. 175 (1993) 7430-7440. [PMID: 8226690]

2. Scott, A.I., Roessner, C.A., Stolowich, N.J., Spencer, J.B., Min, C. and Ozaki, S.I. Biosynthesis of vitamin B12. Discovery of the enzymes for oxidative ring contraction and insertion of the fourth methyl group. FEBS Lett. 331 (1993) 105-108. [PMID: 8405386]

3. Warren, M.J., Raux, E., Schubert, H.L. and Escalante-Semerena, J.C. The biosynthesis of adenosylcobalamin (vitamin B12). Nat. Prod. Rep. 19 (2002) 390-412. [PMID: 12195810]

[EC 1.14.13.83 created 2004]

EC 1.14.13.84

Accepted name: 4-hydroxyacetophenone monooxygenase

Reaction: (4-hydroxyphenyl)ethan-1-one + NADPH + H+ + O2 = 4-hydroxyphenyl acetate + NADP+ + H2O

For diagram of reaction click here.

Other name(s): HAPMO

Systematic name: (4-hydroxyphenyl)ethan-1-one,NADPH:oxygen oxidoreductase (ester-forming)

Comments: Contains FAD. The enzyme from Pseudomonas fluorescens ACB catalyses the conversion of a wide range of acetophenone derivatives. Highest activity occurs with compounds bearing an electron-donating substituent at the para position of the aromatic ring [1]. In the absence of substrate, the enzyme can act as an NAD(P)H oxidase (EC 1.6.3.1).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 156621-13-5

References:

1. Kamerbeek, N.M., Moonen, M.J., van der Ven, J.G., van Berkel, W.J.H., Fraaije, M.W. and Janssen, D.B. 4-Hydroxyacetophenone monooxygenase from Pseudomonas fluorescens ACB: a novel flavoprotein catalyzing Baeyer-Villiger oxidation of aromatic compounds. Eur. J. Biochem. 268 (2001) 2547-2557. [PMID: 11322873 ]

2. Kamerbeek, N.M, Olsthoorn, A.J.J., Fraaije, M.W. and Janssen, D.B. Substrate specificity of a novel Baeyer-Villiger monooxygenase, 4-hydroxyacetophenone monooxygenase. Appl. Environ. Microbiol. 69 (2003) 419-426. [PMID: 12514023]

[EC 1.14.13.84 created 2004]

EC 1.14.13.85

Accepted name: glyceollin synthase

Reaction: 2-(or 4-)dimethylallyl-(6aS,11aS)-3,6a,9-trihydroxypterocarpan + NADPH + H+ + O2 = glyceollin + NADP+ + 2 H2O

For diagram click here.

Other Name(s): dimethylallyl-3,6a,9-trihydroxypterocarpan cyclase

Systematic name: 2-(or 4-)dimethylallyl-(6aS,11aS)-3,6a,9-trihydroxypterocarpan,NADPH:oxygen oxidoreductase (cyclizing)

Comments: A heme-thiolate protein (P-450). Glyceollins II and III are formed from 2-dimethylallyl-(6aS,11aS)-3,6a,9-trihydroxypterocarpan whereas glyceollin I is formed from the 4-isomer.

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

References:

1. Welle, R. and Grisebach, H. Induction of phytoalexin synthesis in soybean: enzymatic cyclization of prenylated pterocarpans to glyceollin isomers. Arch. Biochem. Biophys. 263 (1988) 191-198. [PMID: 3369863]

[EC 1.14.13.85 created 2004]

[EC 1.14.13.86 Deleted entry: 2-hydroxyisoflavanone synthase. This enzyme was classified on the basis of an incorrect reaction. The activity is covered by EC 1.14.13.136 2-hydroxyisoflavanone synthase (EC 1.14.13.86 created 2004, deleted 2013)]

EC 1.14.13.87

Accepted name: licodione synthase

Reaction: liquiritigenin + NADPH + H+ + O2 = licodione + NADP+ + H2O

For diagram click here.

Glossary: licodione = 1-(2,4-dihydroxyphenyl)-3-(4-hydroxyphenyl)propane-1,3-dione

Systematic name: liquiritigenin,NADPH:oxygen oxidoreductase (licodione-forming)

Comments: A heme-thiolate protein (P-450). It probably forms 2-hydroxyliquiritigenin which spontaneously forms licodione. NADH can act instead of NADPH, but more slowly.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 157972-05-9

References:

1. Otani, K., Takahashi, T., Furuya, T. and Ayabe, S. Licodione synthase, a cytochrome P450 monooxygenase catalyzing 2-hydroxylation of 5-deoxyflavanone, in cultured Glycyrrhiza echinata L. cells. Plant Physiol. 105 (1994) 1427-1432. [PMID: 12232298]

2. Akashi, T., Aoki, T. and Ayabe, S. Identification of a cytochrome P450 cDNA encoding (2S)-flavanone 2-hydroxylase of licorice (Glycyrrhiza echinata L.; Fabaceae) which represents licodione synthase and flavone synthase II. FEBS Lett. 431 (1998) 287-290. [PMID: 9708921]

[EC 1.14.13.87 created 2004]

EC 1.14.13.88

Accepted name: flavonoid 3',5'-hydroxylase

Reaction: a flavanone + 2 NADPH + 2 H+ + 2 O2 = a 3',5'-dihydroxyflavanone + 2 NADP+ + 2 H2O (overall reaction)
(1a) a flavanone + NADPH + H+ + O2 = a 3'-hydroxyflavanone + NADP+ + H2O

(1b) a 3'-hydroxyflavanone + NADPH + H+ + O2 = a 3',5'-dihydroxyflavanone + NADP+ + H2O

See diagram for reaction in ampelopsin or dihydrotricetin or taxifolin biosynthesis.

Other Name(s): F3'5'H; F3',5'H

Systematic name: flavanone,NADPH:oxygen oxidoreductase

Comments: A heme-thiolate protein (P-450). The 3',5'-dihydroxyflavanone is formed via the 3'-hydroxyflavanone. In Petunia hybrida the enzyme acts on naringenin, eriodictyol, dihydroquercetin (taxifolin) and dihydrokaempferol (aromadendrin). The enzyme catalyses the hydroxylation of 5,7,4'-trihydroxyflavanone (naringenin) at either the 3' position to form eriodictyol or at both the 3' and 5' positions to form 5,7,3',4',5'-pentahydroxyflavanone (dihydrotricetin). The enzyme also catalyses the hydroxylation of 3,5,7,3',4'-pentahydroxyflavanone (taxifolin) at the 5' position, forming ampelopsin. NADH is not a good substitute for NADPH.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 94047-23-1

References:

1. Menting, J., Scopes, R.K. and Stevenson, T.W. Characterization of flavonoid 3',5'-hydroxylase in microsomal membrane fraction of Petunia hybrida flowers. Plant Physiol. 106 (1994) 633-642. [PMID: 12232356]

2. Shimada, Y., Nakano-Shimada, R., Ohbayashi, M., Okinaka, Y., Kiyokawa, S. and Kikuchi, Y. Expression of chimeric P450 genes encoding flavonoid-3',5'-hydroxylase in transgenic tobacco and petunia plants. FEBS Lett. 461 (1999) 241-245. [PMID: 10567704]

3. de Vetten, N., ter Horst, J., van Schaik, H.P., de Boer, A., Mol, J. and Koes, R. A cytochrome b5 is required for full activity of flavonoid 3',5'-hydroxylase, a cytochrome P450 involved in the formation of blue flower colors. Proc. Natl. Acad. Sci. USA 96 (1999) 778-783. [PMID: 9892710]

[EC 1.14.13.88 created 2004]

EC 1.14.13.89

Accepted name: isoflavone 2'-hydroxylase

Reaction: an isoflavone + NADPH + H+ + O2 = a 2'-hydroxyisoflavone + NADP+ + H2O

For diagram click here.

Other name(s): isoflavone 2'-monooxygenase; CYP81E1; CYP Ge-3

Systematic name: isoflavone,NADPH:oxygen oxidoreductase (2'-hydroxylating)

Comments: A heme-thiolate protein (P-450). Acts on daidzein, formononetin and genistein. EC 1.14.13.53, 4'-methoxyisoflavone 2'-hydroxylase, has the same reaction but is more specific as it requires a 4'-methoxyisoflavone.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 110183-49-8

References:

1. Akashi, T., Aoki, T. and Ayabe, S.-I. CYP81E1, a cytochrome P450 cDNA of licorice (Glycyrrhiza echinata L.), encodes isoflavone 2'-hydroxylase. Biochem. Biophys. Res. Commun. 251 (1998) 67-70. [PMID: 9790908]

[EC 1.14.13.89 created 2005]

[EC 1.14.13.90 Transferred entry: zeaxanthin epoxidase. Now EC 1.14.15.21, zeaxanthin epoxidase (EC 1.14.13.90 created 2005, deleted 2016)]

EC 1.14.13.91

Accepted name: deoxysarpagine hydroxylase

Reaction: 10-deoxysarpagine + NADPH + H+ + O2 = sarpagine + NADP+ + H2O

For diagram click here.

Other name(s): DOSH

Systematic name: 10-deoxysarpagine,NADPH:oxygen oxidoreductase (10-hydroxylating)

Comments: A heme-thiolate protein (P-450).

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

References:

1. Yu, B., Ruppert, M. and Stöckigt, J. Deoxysarpagine hydroxylase — a novel enzyme closing a short side pathway of alkaloid biosynthesis in Rauvolfia. Bioorg. Med. Chem. 10 (2002) 2479-2483. [PMID: 12057637]

[EC 1.14.13.91 created 2005]

EC 1.14.13.92

Accepted name: phenylacetone monooxygenase

Reaction: phenylacetone + NADPH + H+ + O2 = benzyl acetate + NADP+ + H2O

For diagram click here.

Other name(s): PAMO

Systematic name: phenylacetone,NADPH:oxygen oxidoreductase

Comments: A flavoprotein (FAD). NADH cannot replace NADPH as coenzyme. In addition to phenylacetone, which is the best substrate found to date, this Baeyer-Villiger monooxygenase can oxidize other aromatic ketones [1-(4-hydroxyphenyl)propan-2-one, 1-(4-hydroxyphenyl)propan-2-one and 3-phenylbutan-2-one], some alipatic ketones (e.g. dodecan-2-one) and sulfides (e.g. 1-methyl-4-(methylsulfanyl)benzene).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 1005768-90-0

References:

1. Malito, E., Alfieri, A., Fraaije, M.W. and Mattevi, A. Crystal structure of a Baeyer-Villiger monooxygenase. Proc. Natl. Acad. Sci. USA 101 (2004) 13157-13162. [PMID: 15328411]

2. Fraaije, M.W., Wu, J., Heuts, D.P., van Hellemond, E.W., Spelberg, J.H. and Janssen, D.B. Discovery of a thermostable Baeyer-Villiger monooxygenase by genome mining. Appl. Microbiol. Biotechnol. 66 (2005) 393-400. [PMID: 15599520]

[EC 1.14.13.92 created 2005]

EC 1.14.13.93

Accepted name: (+)-abscisic acid 8'-hydroxylase

Reaction: (+)-abscisate + NADPH + H+ + O2 = 8'-hydroxyabscisate + NADP+ + H2O

For diagram click here.

Other name(s): (+)-ABA 8'-hydroxylase; ABA 8'-hydroxylase

Systematic name: abscisate,NADPH:oxygen oxidoreductase (8'-hydroxylating)

Comments: A heme-thiolate protein (P-450). Catalyses the first step in the oxidative degradation of abscisic acid and is considered to be the pivotal enzyme in controlling the rate of degradation of this plant hormone [1]. CO inhibits the reaction, but its effects can be reversed by the presence of blue light [1]. The 8'-hydroxyabscisate formed can be converted into (–)-phaseic acid, most probably spontaneously. Other enzymes involved in the abscisic-acid biosynthesis pathway are EC 1.1.1.288 (xanthoxin dehydrogenase), EC 1.2.3.14 (abscisic aldehyde oxidase) and EC 1.13.11.51 (9-cis-epoxycarotenoid dioxygenase).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 153190-37-5

References:

1. Cutler, A.J., Squires, T.M., Loewen, M.K. and Balsevich, J.J. Induction of (+)-abscisic acid 8' hydroxylase by (+)-abscisic acid in cultured maize cells. J. Exp. Bot. 48 (1997) 1787-1795.

2. Krochko, J.E., Abrams, G.D., Loewen, M.K., Abrams, S.R. and Cutler, A.J. (+)-Abscisic acid 8'-hydroxylase is a cytochrome P450 monooxygenase. Plant Physiol. 118 (1998) 849-860. [PMID: 9808729]

[EC 1.14.13.93 created 2005]

EC 1.14.13.94

Accepted name: lithocholate 6β-hydroxylase

Reaction: lithocholate + NADPH + H+ + O2 = 6β-hydroxylithocholate + NADP+ + H2O

For diagram click here.

Glossary: lithocholic acid = 3α-hydroxy-5β-cholan-24-oic acid
murideoxycholic acid = 3α,6β-dihydroxy-5β-cholan-24-oic acid

Other name(s): lithocholate 6β-monooxygenase; CYP3A10; 6β-hydroxylase; cytochrome P450 3A10/lithocholic acid 6β-hydroxylase

Systematic name: lithocholate,NADPH:oxygen oxidoreductase (6β-hydroxylating)

Comments: A heme-thiolate protein (P-450). Expression of the gene for this enzyme is 50-fold higher in male compared to female hamsters [1].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9075-83-6

References:

1. Teixeira, J. and Gil, G. Cloning, expression, and regulation of lithocholic acid 6β-hydroxylase. J. Biol. Chem. 266 (1991) 21030-21036. [PMID: 1840595]

2. Chang, T.K., Teixeira, J., Gil, G. and Waxman, D.J. The lithocholic acid 6β-hydroxylase cytochrome P-450, CYP 3A10, is an active catalyst of steroid-hormone 6β-hydroxylation. Biochem. J. 291 (1993) 429-433. [PMID: 8484723]

3. Subramanian, A., Wang, J. and Gil, G. STAT 5 and NF-Y are involved in expression and growth hormone-mediated sexually dimorphic regulation of cytochrome P450 3A10/lithocholic acid 6β-hydroxylase. Nucleic Acids Res. 26 (1998) 2173-2178. [PMID: 9547277]

4. Russell, D.W. The enzymes, regulation, and genetics of bile acid synthesis. Annu. Rev. Biochem. 72 (2003) 137-174. [PMID: 12543708]

[EC 1.14.13.94 created 2005]

[EC 1.14.13.95 Transferred entry: 7α-hydroxycholest-4-en-3-one 12α-hydroxylase. Now EC 1.14.18.8, 7α-hydroxycholest-4-en-3-one 12α-hydroxylase (EC 1.14.13.95 created 2005, deleted 2015)]

EC 1.14.13.96

Accepted name: 5β-cholestane-3α,7α-diol 12α-hydroxylase

Reaction: 5β-cholestane-3α,7α-diol + NADPH + H+ + O2 = 5β-cholestane-3α,7α,12α-triol + NADP+ + H2O

For diagram click here.

Other name(s): 5β-cholestane-3α,7α-diol 12α-monooxygenase; sterol 12α-hydroxylase (ambiguous); CYP8B1; cytochrome P450 8B1

Systematic name: 5β-cholestane-3α,7α-diol,NADPH:oxygen oxidoreductase (12α-hydroxylating)

Comments: A heme-thiolate protein (P-450). This is the key enzyme in the biosynthesis of the bile acid cholic acid (3α,7α,12α-trihydroxy-5β-cholanoic acid). The activity of this enzyme determines the biosynthetic ratio between cholic acid and chenodeoxycholic acid [3]. The enzyme can also hydroxylate the substrate at the 25 and 26 position, but to a lesser extent [1].

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

References:

1. Hansson, R. and Wikvall, K. Hydroxylations in biosynthesis of bile acids. Cytochrome P-450 LM4 and 12α-hydroxylation of 5β-cholestane-3α,7α-diol. Eur. J. Biochem. 125 (1982) 423-429. [PMID: 6811268]

2. Hansson, R. and Wikvall, K. Hydroxylations in biosynthesis and metabolism of bile acids. Catalytic properties of different forms of cytochrome P-450. J. Biol. Chem. 255 (1980) 1643-1649. [PMID: 6766451]

3. Lundell, K. and Wikvall, K. Gene structure of pig sterol 12α-hydroxylase (CYP8B1) and expression in fetal liver: comparison with expression of taurochenodeoxycholic acid 6α-hydroxylase (CYP4A21). Biochim. Biophys. Acta 1634 (2003) 86-96. [PMID: 14643796]

4. del Castillo-Olivares, A. and Gil, G. α1-Fetoprotein transcription factor is required for the expression of sterol 12α-hydroxylase, the specific enzyme for cholic acid synthesis. Potential role in the bile acid-mediated regulation of gene transcription. J. Biol. Chem. 275 (2000) 17793-17799. [PMID: 10747975]

5. Yang, Y., Zhang, M., Eggertsen, G. and Chiang, J.Y. On the mechanism of bile acid inhibition of rat sterol 12α-hydroxylase gene (CYP8B1) transcription: roles of α-fetoprotein transcription factor and hepatocyte nuclear factor 4α. Biochim. Biophys. Acta 1583 (2002) 63-73. [PMID: 12069850]

6. Russell, D.W. The enzymes, regulation, and genetics of bile acid synthesis. Annu. Rev. Biochem. 72 (2003) 137-174. [PMID: 12543708]

[EC 1.14.13.96 created 2005]

EC 1.14.13.97

Accepted name: taurochenodeoxycholate 6α-hydroxylase

Reaction: (1) taurochenodeoxycholate + NADPH + H+ + O2 = taurohyocholate + NADP+ + H2O

(2) lithocholate + NADPH + H+ + O2 = hyodeoxycholate + NADP+ + H2O

For diagram click here.

Glossary: taurochenodeoxycholic acid = N-(3α,7α-dihydroxy-5β-cholan-24-oyl)taurine
taurohyocholic acid = N-(3α,6α,7α-trihydroxy-5β-cholan-24-oyl)taurine
hyodeoxycholate = 3α,6α-dihydroxy-5β-cholanoate

Other name(s): CYP3A4; CYP4A21; taurochenodeoxycholate 6α-monooxygenase

Systematic name: taurochenodeoxycholate,NADPH:oxygen oxidoreductase (6α-hydroxylating)

Comments: A heme-thiolate protein (P-450). Requires cytochrome b5 for maximal activity. Acts on taurochenodeoxycholate, taurodeoxycholate and less readily on lithocholate and chenodeoxycholate. In adult pig (Sus scrofa), hyocholic acid replaces cholic acid as a primary bile acid [5].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 105669-85-0

References:

1. Araya, Z. and Wikvall, K. 6α-Hydroxylation of taurochenodeoxycholic acid and lithocholic acid by CYP3A4 in human liver microsomes. Biochim. Biophys. Acta 1438 (1999) 47-54. [PMID: 10216279]

2. Araya, Z., Hellman, U. and Hansson, R. Characterisation of taurochenodeoxycholic acid 6α-hydroxylase from pig liver microsomes. Eur. J. Biochem. 231 (1995) 855-861. [PMID: 7649186]

3. Kramer, W., Sauber, K., Baringhaus, K.H., Kurz, M., Stengelin, S., Lange, G., Corsiero, D., Girbig, F., Konig, W. and Weyland, C. Identification of the bile acid-binding site of the ileal lipid-binding protein by photoaffinity labeling, matrix-assisted laser desorption ionization-mass spectrometry, and NMR structure. J. Biol. Chem. 276 (2001) 7291-7301. [PMID: 11069906]

4. Lundell, K., Hansson, R. and Wikvall, K. Cloning and expression of a pig liver taurochenodeoxycholic acid 6α-hydroxylase (CYP4A21): a novel member of the CYP4A subfamily. J. Biol. Chem. 276 (2001) 9606-9612. [PMID: 11113117]

5. Lundell, K. and Wikvall, K. Gene structure of pig sterol 12α-hydroxylase (CYP8B1) and expression in fetal liver: comparison with expression of taurochenodeoxycholic acid 6α-hydroxylase (CYP4A21). Biochim. Biophys. Acta 1634 (2003) 86-96. [PMID: 14643796]

6. Russell, D.W. The enzymes, regulation, and genetics of bile acid synthesis. Annu. Rev. Biochem. 72 (2003) 137-174. [PMID: 12543708]

[EC 1.14.13.97 created 2005]

[EC 1.14.13.98 Transferred entry: cholesterol 24-hydroxylase, Now EC 1.14.14.25, cholesterol 24-hydroxylase (EC 1.14.13.98 created 2005, deleted 2016)]

[EC 1.14.13.99 Transferred entry: 24-hydroxycholesterol 7α-hydroxylase, now classified as EC 1.14.14.26, 24-hydroxycholesterol 7α-hydroxylase (EC 1.14.13.99 created 2005, deleted 2016)]

[EC 1.14.13.100 Transferred entry: 25/26-hydroxycholesterol 7α-hydroxylase. Now classified as EC 1.14.14.29, 25/26-hydroxycholesterol 7α-hydroxylase (EC 1.14.13.100 created 2005, modified 2013 (EC 1.14.13.60 created 1999, incorporated 2013), deleted 2016)]


Continued with EC 1.14.13.101 to EC 1.14.13.150
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