ExplorEnz: EC 1*

References:

1.	Liu, X., Dong, Y., Li, X., Ren, Y., Li, Y., Wang, W., Wang, L. and Feng, L. Characterization of the anthranilate degradation pathway in Geobacillus thermodenitrificans NG80-2. Microbiology 156 (2010) 589–595. [DOI] [PMID: 19942660]

[EC 1.14.14.8 created 2010]

1.14.14.9

Accepted name:

4-hydroxyphenylacetate 3-monooxygenase

Reaction:

4-hydroxyphenylacetate + FADH₂ + O₂ = 3,4-dihydroxyphenylacetate + FAD + H₂O

Other name(s):

p-hydroxyphenylacetate 3-hydroxylase; 4-hydroxyphenylacetic acid-3-hydroxylase; p-hydroxyphenylacetate hydroxylase (FAD); 4 HPA 3-hydroxylase; p-hydroxyphenylacetate 3-hydroxylase (FAD); HpaB

Systematic name:

4-hydroxyphenylacetate,FADH₂:oxygen oxidoreductase (3-hydroxylating)

Comments:

The enzyme from Escherichia coli attacks a broad spectrum of phenolic compounds. The enzyme uses FADH₂ as a substrate rather than a cofactor [4]. FADH₂ is provided by EC 1.5.1.36, flavin reductase (NADH) [5,6].

Links to other databases:

BRENDA, EAWAG-BBD, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 37256-71-6

References:

1.	Adachi, K., Takeda, Y., Senoh, S. and Kita, H. Metabolism of p-hydroxyphenylacetic acid in Pseudomonas ovalis. Biochim. Biophys. Acta 93 (1964) 483–493. [DOI] [PMID: 14263147]
2.	Prieto, M.A., Perez-Aranda, A. and Garcia, J.L. Characterization of an Escherichia coli aromatic hydroxylase with a broad substrate range. J. Bacteriol. 175 (1993) 2162–2167. [DOI] [PMID: 8458860]
3.	Prieto, M.A. and Garcia, J.L. Molecular characterization of 4-hydroxyphenylacetate 3-hydroxylase of Escherichia coli. A two-protein component enzyme. J. Biol. Chem. 269 (1994) 22823–22829. [PMID: 8077235]
4.	Xun, L. and Sandvik, E.R. Characterization of 4-hydroxyphenylacetate 3-hydroxylase (HpaB) of Escherichia coli as a reduced flavin adenine dinucleotide-utilizing monooxygenase. Appl. Environ. Microbiol. 66 (2000) 481–486. [DOI] [PMID: 10653707]
5.	Galan, B., Diaz, E., Prieto, M.A. and Garcia, J.L. Functional analysis of the small component of the 4-hydroxyphenylacetate 3-monooxygenase of Escherichia coli W: a prototype of a new Flavin:NAD(P)H reductase subfamily. J. Bacteriol. 182 (2000) 627–636. [DOI] [PMID: 10633095]
6.	Louie, T.M., Xie, X.S. and Xun, L. Coordinated production and utilization of FADH₂ by NAD(P)H-flavin oxidoreductase and 4-hydroxyphenylacetate 3-monooxygenase. Biochemistry 42 (2003) 7509–7517. [DOI] [PMID: 12809507]

[EC 1.14.14.9 created 1972 as EC 1.14.13.3, transferred 2011 to EC 1.14.14.9]

1.14.14.10

Accepted name:

nitrilotriacetate monooxygenase

Reaction:

nitrilotriacetate + FMNH₂ + H⁺ + O₂ = iminodiacetate + glyoxylate + FMN + H₂O

Systematic name:

nitrilotriacetate,FMNH₂:oxygen oxidoreductase (glyoxylate-forming)

Comments:

Requires Mg²⁺. The enzyme from Aminobacter aminovorans (previously Chelatobacter heintzii) is part of a two component system that also includes EC 1.5.1.42 (FMN reductase), which provides reduced flavin mononucleotide for this enzyme.

Links to other databases:

BRENDA, EAWAG-BBD, EXPASY, Gene, KEGG, MetaCyc

References:

1.	Uetz, T., Schneider, R., Snozzi, M. and Egli, T. Purification and characterization of a two-component monooxygenase that hydroxylates nitrilotriacetate from "Chelatobacter" strain ATCC 29600. J. Bacteriol. 174 (1992) 1179–1188. [DOI] [PMID: 1735711]
2.	Knobel, H.R., Egli, T. and van der Meer, J.R. Cloning and characterization of the genes encoding nitrilotriacetate monooxygenase of Chelatobacter heintzii ATCC 29600. J. Bacteriol. 178 (1996) 6123–6132. [DOI] [PMID: 8892809]
3.	Xu, Y., Mortimer, M.W., Fisher, T.S., Kahn, M.L., Brockman, F.J. and Xun, L. Cloning, sequencing, and analysis of a gene cluster from Chelatobacter heintzii ATCC 29600 encoding nitrilotriacetate monooxygenase and NADH:flavin mononucleotide oxidoreductase. J. Bacteriol. 179 (1997) 1112–1116. [DOI] [PMID: 9023192]

[EC 1.14.14.10 created 2011]

1.14.14.11

Accepted name:

styrene monooxygenase

Reaction:

styrene + FADH₂ + O₂ = (S)-2-phenyloxirane + FAD + H₂O

Other name(s):

StyA; SMO; NSMOA

Systematic name:

styrene,FADH₂:oxygen oxidoreductase

Comments:

The enzyme catalyses the first step in the aerobic styrene degradation pathway. It forms a two-component system with a reductase (StyB) that utilizes NADH to reduce flavin-adenine dinucleotide, which is then transferred to the oxygenase.

Links to other databases:

References:

1.	Otto, K., Hofstetter, K., Rothlisberger, M., Witholt, B. and Schmid, A. Biochemical characterization of StyAB from Pseudomonas sp. strain VLB120 as a two-component flavin-diffusible monooxygenase. J. Bacteriol. 186 (2004) 5292–5302. [DOI] [PMID: 15292130]
2.	Tischler, D., Kermer, R., Groning, J.A., Kaschabek, S.R., van Berkel, W.J. and Schlomann, M. StyA1 and StyA2B from Rhodococcus opacus 1CP: a multifunctional styrene monooxygenase system. J. Bacteriol. 192 (2010) 5220–5227. [DOI] [PMID: 20675468]

[EC 1.14.14.11 created 2011]

1.14.14.12

Accepted name:

3-hydroxy-9,10-secoandrosta-1,3,5(10)-triene-9,17-dione monooxygenase

Reaction:

3-hydroxy-9,10-secoandrosta-1,3,5(10)-triene-9,17-dione + FMNH₂ + O₂ = 3,4-dihydroxy-9,10-secoandrosta-1,3,5(10)-triene-9,17-dione + FMN + H₂O

Other name(s):

HsaA

Systematic name:

3-hydroxy-9,10-secoandrosta-1,3,5(10)-triene-9,17-dione,FMNH₂:oxygen oxidoreductase

Comments:

This bacterial enzyme participates in the degradation of several steroids, including cholesterol and testosterone. It can use either FADH or FMNH₂ as flavin cofactor. The enzyme forms a two-component system with a reductase (HsaB) that utilizes NADH to reduce the flavin, which is then transferred to the oxygenase subunit.

Links to other databases:

BRENDA, EAWAG-BBD, EXPASY, Gene, KEGG, MetaCyc, PDB

References:

1.	Dresen, C., Lin, L.Y., D'Angelo, I., Tocheva, E.I., Strynadka, N. and Eltis, L.D. A flavin-dependent monooxygenase from Mycobacterium tuberculosis involved in cholesterol catabolism. J. Biol. Chem. 285 (2010) 22264–22275. [DOI] [PMID: 20448045]

[EC 1.14.14.12 created 2011]

1.14.14.13

Accepted name:

4-(γ-L-glutamylamino)butanoyl-[BtrI acyl-carrier protein] monooxygenase

Reaction:

4-(γ-L-glutamylamino)butanoyl-[BtrI acyl-carrier protein] + FMNH₂ + O₂ = 4-(γ-L-glutamylamino)-(2S)-2-hydroxybutanoyl-[BtrI acyl-carrier protein] + FMN + H₂O

Other name(s):

btrO (gene name)

Systematic name:

4-(γ-L-glutamylamino)butanoyl-[BtrI acyl-carrier protein],FMNH₂:oxygen oxidoreductase (2-hydroxylating)

Comments:

Catalyses a step in the biosynthesis of the side chain of the aminoglycoside antibiotics of the butirosin family. FMNH₂ is used as a free cofactor. Forms a complex with a dedicated NAD(P)H:FMN oxidoreductase. The enzyme is not able to hydroxylate free substrates, activation by the acyl-carrier protein is mandatory. Octanoyl-S-[BtrI acyl-carrier protein] is also accepted.

Links to other databases:

References:

1.	Li, Y., Llewellyn, N.M., Giri, R., Huang, F. and Spencer, J.B. Biosynthesis of the unique amino acid side chain of butirosin: possible protective-group chemistry in an acyl carrier protein-mediated pathway. Chem. Biol. 12 (2005) 665–675. [DOI] [PMID: 15975512]

[EC 1.14.14.13 created 2012]

1.14.14.14

Accepted name:

aromatase

Reaction:

(1) testosterone + 3 O₂ + 3 [reduced NADPH—hemoprotein reductase] = 17β-estradiol + formate + 4 H₂O + 3 [oxidized NADPH—hemoprotein reductase] (overall reaction)
(1a) testosterone + O₂ + [reduced NADPH—hemoprotein reductase] = 19-hydroxytestosterone + H₂O + [oxidized NADPH—hemoprotein reductase]
(1b) 19-hydroxytestosterone + O₂ + [reduced NADPH—hemoprotein reductase] = 19-oxotestosterone + 2 H₂O + [oxidized NADPH—hemoprotein reductase]
(1c) 19-oxotestosterone + O₂ + [reduced NADPH—hemoprotein reductase] = 17β-estradiol + formate + H₂O + [oxidized NADPH—hemoprotein reductase]
(2) androst-4-ene-3,17-dione + 3 O₂ + 3 [reduced NADPH—hemoprotein reductase] = estrone + formate + 4 H₂O + 3 [oxidized NADPH—hemoprotein reductase] (overall reaction)
(2a) androst-4-ene-3,17-dione + O₂ + [reduced NADPH—hemoprotein reductase] = 19-hydroxyandrost-4-ene-3,17-dione + H₂O + [oxidized NADPH—hemoprotein reductase]
(2b) 19-hydroxyandrost-4-ene-3,17-dione + O₂ + [reduced NADPH—hemoprotein reductase] = 19-oxo-androst-4-ene-3,17-dione + 2 H₂O + [oxidized NADPH—hemoprotein reductase]
(2c) 19-oxoandrost-4-ene-3,17-dione + O₂ + [reduced NADPH—hemoprotein reductase] = estrone + formate + H₂O + [oxidized NADPH—hemoprotein reductase]

Other name(s):

CYP19A1 (gene name); estrogen synthetase (incorrect)

Systematic name:

testosteronel,NADPH—hemoprotein reductase:oxygen oxidoreductase (17β-estradiol-forming)

Comments:

A cytochrome P-450. The enzyme catalyses three sequential hydroxylations of the androgens androst-4-ene-3,17-dione and testosterone, resulting in their aromatization and forming the estrogens estrone and 17β-estradiol, respectively. The direct electron donor to the enzyme is EC 1.6.2.4, NADPH—hemoprotein reductase.

Links to other databases:

References:

1.	Thompson, E.A., Jr. and Siiteri, P.K. The involvement of human placental microsomal cytochrome P-450 in aromatization. J. Biol. Chem. 249 (1974) 5373–5378. [PMID: 4370479]
2.	Fishman, J. and Goto, J. Mechanism of estrogen biosynthesis. Participation of multiple enzyme sites in placental aromatase hydroxylations. J. Biol. Chem. 256 (1981) 4466–4471. [PMID: 7217091]
3.	Kellis, J.T., Jr. and Vickery, L.E. Purification and characterization of human placental aromatase cytochrome P-450. J. Biol. Chem. 262 (1987) 4413–4420. [PMID: 3104339]
4.	Ghosh, D., Griswold, J., Erman, M. and Pangborn, W. Structural basis for androgen specificity and oestrogen synthesis in human aromatase. Nature 457 (2009) 219–223. [DOI] [PMID: 19129847]

[EC 1.14.14.14 created 2013]

1.14.14.15

Accepted name:

(3S)-3-amino-3-(3-chloro-4-hydroxyphenyl)propanoyl-[peptidyl-carrier protein SgcC2] monooxygenase

Reaction:

(3S)-3-amino-3-(3-chloro-4-hydroxyphenyl)propanoyl-[peptidyl-carrier protein SgcC2] + FADH₂ + O₂ = (3S)-3-amino-3-(3-chloro-4,5-dihydroxyphenyl)propanoyl-[peptidyl-carrier protein SgcC2] + FAD + H₂O

Other name(s):

SgcC

Systematic name:

(3S)-3-amino-3-(3-chloro-4-hydroxyphenyl)propanoyl-[peptidyl-carrier protein SgcC2],FADH₂:oxygen oxidoreductase (5-hydroxylating)

Comments:

The enzyme from the bacterium Streptomyces globisporus is involved in the biosynthesis of the (S)-3-chloro-5-hydroxy-β-tyrosine moiety prior to incorporation into the chromoprotein antitumor antibiotic C-1027.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

References:

1.	Lin, S., Van Lanen, S.G. and Shen, B. Characterization of the two-component, FAD-dependent monooxygenase SgcC that requires carrier protein-tethered substrates for the biosynthesis of the enediyne antitumor antibiotic C-1027. J. Am. Chem. Soc. 130 (2008) 6616–6623. [DOI] [PMID: 18426211]

[EC 1.14.14.15 created 2014]

1.14.14.16

Accepted name:

steroid 21-monooxygenase

Reaction:

a C₂₁ steroid + [reduced NADPH—hemoprotein reductase] + O₂ = a 21-hydroxy-C₂₁-steroid + [oxidized NADPH—hemoprotein reductase] + H₂O

Other name(s):

steroid 21-hydroxylase; 21-hydroxylase; P450c21; CYP21A2 (gene name)

Systematic name:

steroid,NADPH—hemoprotein reductase:oxygen oxidoreductase (21-hydroxylating)

Comments:

A P-450 heme-thiolate protein responsible for the conversion of progesterone and 17α-hydroxyprogesterone to their respective 21-hydroxylated derivatives, 11-deoxycorticosterone and 11-deoxycortisol. Involved in the biosynthesis of the hormones aldosterone and cortisol. The electron donor is EC 1.6.2.4, NADPH—hemoprotein reductase.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 9029-68-9

References:

1.	Hayano, M. and Dorfman, R.I. The action of adrenal homogenates on progesterone, 17-hydroxyprogesterone and 21-desoxycortisone. Arch. Biochem. Biophys. 36 (1952) 237–239. [DOI] [PMID: 14934270]
2.	Plager, J.E. and Samuels, L.T. Synthesis of C14-17-hydroxy-11-desoxycorticosterone and 17-hydroxycorticosterone by fractionated extracts of adrenal homogenates. Arch. Biochem. Biophys. 42 (1953) 477–478. [DOI] [PMID: 13031650]
3.	Ryan, K.J. and Engel, L.L. Hydroxylation of steroids at carbon 21. J. Biol. Chem. 225 (1957) 103–114. [PMID: 13416221]
4.	Kominami, S., Ochi, H., Kobayashi, Y. and Takemori, S. Studies on the steroid hydroxylation system in adrenal cortex microsomes. Purification and characterization of cytochrome P-450 specific for steroid C-21 hydroxylation. J. Biol. Chem. 255 (1980) 3386–3394. [PMID: 6767716]
5.	Martineau, I., Belanger, A., Tchernof, A. and Tremblay, Y. Molecular cloning and expression of guinea pig cytochrome P450c21 cDNA (steroid 21-hydroxylase) isolated from the adrenals. J. Steroid Biochem. Mol. Biol. 86 (2003) 123–132. [DOI] [PMID: 14568563]
6.	Arase, M., Waterman, M.R. and Kagawa, N. Purification and characterization of bovine steroid 21-hydroxylase (P450c21) efficiently expressed in Escherichia coli. Biochem. Biophys. Res. Commun. 344 (2006) 400–405. [DOI] [PMID: 16597434]

[EC 1.14.14.16 created 1961 as EC 1.99.1.11, transferred 1965 to EC 1.14.1.8, transferred 1972 to EC 1.14.99.10, modified 2013, transferred 2015 to EC 1.14.14.16]

1.14.14.17

Accepted name:

squalene monooxygenase

Reaction:

squalene + [reduced NADPH—hemoprotein reductase] + O₂ = (3S)-2,3-epoxy-2,3-dihydrosqualene + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of α-onocerin biosynthesis, click here and for diagram of triterpenoid biosynthesis, click here

Other name(s):

squalene epoxidase; squalene-2,3-epoxide cyclase; squalene 2,3-oxidocyclase; squalene hydroxylase; squalene oxydocyclase; squalene-2,3-epoxidase

Systematic name:

squalene,NADPH—hemoprotein:oxygen oxidoreductase (2,3-epoxidizing)

Comments:

A flavoprotein (FAD). This enzyme, together with EC 5.4.99.7, lanosterol synthase, was formerly known as squalene oxidocyclase. The electron donor is EC 1.6.2.4, NADPH—hemoprotein reductase [5,7].

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 9029-62-3

References:

1.	Corey, E.J., Russey, W.E. and Ortiz de Montellano, P.R. 2,3-Oxidosqualene, an intermediate in the biological synthesis of sterols from squalene. J. Am. Chem. Soc. 88 (1966) 4750–4751. [PMID: 5918046]
2.	Tchen, T.T. and Bloch, K. On the conversion of squalene to lanosterol in vitro. J. Biol. Chem. 226 (1957) 921–930. [PMID: 13438881]
3.	van Tamelen, E.E., Willett, J.D., Clayton, R.B. and Lord, K.E. Enzymic conversion of squalene 2,3-oxide to lanosterol and cholesterol. J. Am. Chem. Soc. 88 (1966) 4752–4754. [PMID: 5918048]
4.	Yamamoto, S. and Bloch, K. Studies on squalene epoxidase of rat liver. J. Biol. Chem. 245 (1970) 1670–1674. [PMID: 5438357]
5.	Ono, T. and Bloch, K. Solubilization and partial characterization of rat liver squalene epoxidase. J. Biol. Chem. 250 (1975) 1571–1579. [PMID: 234459]
6.	Satoh, T., Horie, M., Watanabe, H., Tsuchiya, Y. and Kamei, T. Enzymatic properties of squalene epoxidase from Saccharomyces cerevisiae. Biol. Pharm. Bull. 16 (1993) 349–352. [PMID: 8358382]
7.	Chugh, A., Ray, A. and Gupta, J.B. Squalene epoxidase as hypocholesterolemic drug target revisited. Prog. Lipid Res. 42 (2003) 37–50. [DOI] [PMID: 12467639]
8.	He, F., Zhu, Y., He, M. and Zhang, Y. Molecular cloning and characterization of the gene encoding squalene epoxidase in Panax notoginseng. DNA Seq 19 (2008) 270–273. [DOI] [PMID: 17852349]

[EC 1.14.14.17 created 1961 as EC 1.99.1.13, transferred 1965 to EC 1.14.1.3, part transferred 1972 to EC 1.14.99.7, transferred 2011 to EC 1.14.13.132, transferred 2015 to EC 1.14.14.17]

1.14.14.18

Accepted name:

heme oxygenase (biliverdin-producing)

Reaction:

protoheme + 3 [reduced NADPH—hemoprotein reductase] + 3 O₂ = biliverdin + Fe²⁺ + CO + 3 [oxidized NADPH—hemoprotein reductase] + 3 H₂O

For diagram of the reaction mechanism, click here

Other name(s):

ORP33 proteins; haem oxygenase (ambiguous); heme oxygenase (decyclizing) (ambiguous); heme oxidase (ambiguous); haem oxidase (ambiguous); heme oxygenase (ambiguous); heme,hydrogen-donor:oxygen oxidoreductase (α-methene-oxidizing, hydroxylating)

Systematic name:

protoheme,NADPH—hemoprotein reductase:oxygen oxidoreductase (α-methene-oxidizing, hydroxylating)

Comments:

This mammalian enzyme participates in the degradation of heme. The terminal oxygen atoms that are incorporated into the carbonyl groups of pyrrole rings A and B of biliverdin are derived from two separate oxygen molecules [4]. The third oxygen molecule provides the oxygen atom that converts the α-carbon to CO. The enzyme requires NAD(P)H and EC 1.6.2.4, NADPH—hemoprotein reductase. cf. EC 1.14.15.20, heme oxygenase (biliverdin-producing, ferredoxin).

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 9059-22-7

References:

1.	Maines, M.D., Ibrahim, N.G. and Kappas, K. Solubilization and partial purification of heme oxygenase from rat liver. J. Biol. Chem. 252 (1977) 5900–5903. [PMID: 18477]
2.	Sunderman, F.W., Jr., Downs, J.R., Reid, M.C. and Bibeau, L.M. Gas-chromatographic assay for heme oxygenase activity. Clin. Chem. 28 (1982) 2026–2032. [PMID: 6897023]
3.	Yoshida, T., Takahashi, S. and Kikuchi, J. Partial purification and reconstitution of the heme oxygenase system from pig spleen microsomes. J. Biochem. (Tokyo) 75 (1974) 1187–1191. [PMID: 4370250]
4.	Noguchi, M., Yoshida, T. and Kikuchi, G. Specific requirement of NADPH-cytochrome c reductase for the microsomal heme oxygenase reaction yielding biliverdin IX α. FEBS Lett. 98 (1979) 281–284. [DOI] [PMID: 105935]
5.	Lad, L., Schuller, D.J., Shimizu, H., Friedman, J., Li, H., Ortiz de Montellano, P.R. and Poulos, T.L. Comparison of the heme-free and -bound crystal structures of human heme oxygenase-1. J. Biol. Chem. 278 (2003) 7834–7843. [DOI] [PMID: 12500973]

[EC 1.14.14.18 created 1972 as EC 1.14.99.3, modified 2006, transferred 2015 to EC 1.14.14.18, modified 2016]

1.14.14.19

Accepted name:

steroid 17α-monooxygenase

Reaction:

a C₂₁-steroid + [reduced NADPH—hemoprotein reductase] + O₂ = a 17α-hydroxy-C₂₁-steroid + [oxidized NADPH—hemoprotein reductase] + H₂O

Other name(s):

steroid 17α-hydroxylase; cytochrome P-450 17α; cytochrome P-450 (P-450 17α,lyase); 17α-hydroxylase-C17,20 lyase; CYP17; CYP17A1 (gene name)

Systematic name:

steroid,NADPH—hemoprotein reductase:oxygen oxidoreductase (17α-hydroxylating)

Comments:

Requires NADPH and EC 1.6.2.4, NADPH—hemoprotein reductase. A microsomal hemeprotein that catalyses two independent reactions at the same active site - the 17α-hydroxylation of pregnenolone and progesterone, which is part of glucocorticoid hormones biosynthesis, and the conversion of the 17α-hydroxylated products via a 17,20-lyase reaction to form androstenedione and dehydroepiandrosterone, leading to sex hormone biosynthesis (EC 1.14.14.32, 17α-hydroxyprogesterone deacetylase). The ratio of the 17α-hydroxylase and 17,20-lyase activities is an important factor in determining the directions of steroid hormone biosynthesis towards biosynthesis of glucocorticoid or sex hormones.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 9029-67-8

References:

1.	Lynn, W.S. and Brown, R.H. The conversion of progesterone to androgens by testes. J. Biol. Chem. 232 (1958) 1015–1030. [PMID: 13549484]
2.	Yoshida, K.-I., Oshima, H. and Troen, P. Studies of the human testis. XIII. Properties of nicotinamide adenine dinucleotide (reduced form)-linked 17α-hydroxylation. J. Clin. Endocrinol. Metab. 50 (1980) 895–899. [DOI] [PMID: 6966286]
3.	Gilep, A.A., Estabrook, R.W. and Usanov, S.A. Molecular cloning and heterologous expression in E. coli of cytochrome P45017α. Comparison of structural and functional properties of substrate-specific cytochromes P450 from different species. Biochemistry (Mosc.) 68 (2003) 86–98. [PMID: 12693981]
4.	Kolar, N.W., Swart, A.C., Mason, J.I. and Swart, P. Functional expression and characterisation of human cytochrome P45017α in Pichia pastoris. J. Biotechnol. 129 (2007) 635–644. [DOI] [PMID: 17386955]
5.	Pechurskaya, T.A., Lukashevich, O.P., Gilep, A.A. and Usanov, S.A. Engineering, expression, and purification of "soluble" human cytochrome P45017α and its functional characterization. Biochemistry (Mosc.) 73 (2008) 806–811. [PMID: 18707589]

[EC 1.14.14.19 created 1961 as EC 1.99.1.9, transferred 1965 to EC 1.14.1.7, transferred 1972 to EC 1.14.99.9, modified 2013, transferred 2015 to EC 1.14.14.19]

1.14.14.20

Accepted name:

phenol 2-monooxygenase (FADH₂)

Reaction:

phenol + FADH₂ + O₂ = catechol + FAD + H₂O

Other name(s):

pheA1 (gene name)

Systematic name:

phenol,FADH₂:oxygen oxidoreductase (2-hydroxylating)

Comments:

The enzyme catalyses the ortho-hydroxylation of simple phenols into the corresponding catechols. It accepts 4-methylphenol, 4-chlorophenol, and 4-fluorophenol [1] as well as 4-nitrophenol, 3-nitrophenol, and resorcinol [3]. The enzyme is part of a two-component system that also includes an NADH-dependent flavin reductase. It is strictly dependent on FADH₂ and does not accept FMNH₂ [1,3]. cf. EC 1.14.13.7, phenol 2-monooxygenase (NADPH).

Links to other databases:

References:

1.	Kirchner, U., Westphal, A.H., Muller, R. and van Berkel, W.J. Phenol hydroxylase from Bacillus thermoglucosidasius A7, a two-protein component monooxygenase with a dual role for FAD. J. Biol. Chem. 278 (2003) 47545–47553. [DOI] [PMID: 12968028]
2.	van den Heuvel, R.H., Westphal, A.H., Heck, A.J., Walsh, M.A., Rovida, S., van Berkel, W.J. and Mattevi, A. Structural studies on flavin reductase PheA2 reveal binding of NAD in an unusual folded conformation and support novel mechanism of action. J. Biol. Chem. 279 (2004) 12860–12867. [DOI] [PMID: 14703520]
3.	Saa, L., Jaureguibeitia, A., Largo, E., Llama, M.J. and Serra, J.L. Cloning, purification and characterization of two components of phenol hydroxylase from Rhodococcus erythropolis UPV-1. Appl. Microbiol. Biotechnol. 86 (2010) 201–211. [DOI] [PMID: 19787347]

[EC 1.14.14.20 created 2016]

1.14.14.21

Accepted name:

dibenzothiophene monooxygenase

Reaction:

dibenzothiophene + 2 FMNH₂ + 2 O₂ = dibenzothiophene-5,5-dioxide + 2 FMN + 2 H₂O (overall reaction)
(1a) dibenzothiophene + FMNH₂ + O₂ = dibenzothiophene-5-oxide + FMN + H₂O
(1b) dibenzothiophene-5-oxide + FMNH₂ + O₂ = dibenzothiophene-5,5-dioxide + FMN + H₂O

Glossary:

dibenzothiophene-5,5-dioxide = dibenzothiophene sulfone

Other name(s):

dszC (gene name)

Systematic name:

dibenzothiophene,FMNH₂:oxygen oxidoreductase

Comments:

This bacterial enzyme catalyses the first two steps in the desulfurization pathway of dibenzothiophenes, the oxidation of dibenzothiophene into dibenzothiophene sulfone via dibenzothiophene-5-oxide. The enzyme forms a two-component system with a dedicated NADH-dependent FMN reductase (EC 1.5.1.42) encoded by the dszD gene, which also interacts with EC 1.14.14.22, dibenzothiophene sulfone monooxygenase.

Links to other databases:

References:

1.	Gray, K.A., Pogrebinsky, O.S., Mrachko, G.T., Xi, L., Monticello, D.J. and Squires, C.H. Molecular mechanisms of biocatalytic desulfurization of fossil fuels. Nat. Biotechnol. 14 (1996) 1705–1709. [DOI] [PMID: 9634856]
2.	Liu, S., Zhang, C., Su, T., Wei, T., Zhu, D., Wang, K., Huang, Y., Dong, Y., Yin, K., Xu, S., Xu, P. and Gu, L. Crystal structure of DszC from Rhodococcus sp. XP at 1.79 Å. Proteins 82 (2014) 1708–1720. [DOI] [PMID: 24470304]
3.	Guan, L.J., Lee, W.C., Wang, S., Ohshiro, T., Izumi, Y., Ohtsuka, J. and Tanokura, M. Crystal structures of apo-DszC and FMN-bound DszC from Rhodococcus erythropolis D-1. FEBS J. 282 (2015) 3126–3135. [DOI] [PMID: 25627402]

[EC 1.14.14.21 created 2016]

1.14.14.22

Accepted name:

dibenzothiophene sulfone monooxygenase

Reaction:

dibenzothiophene-5,5-dioxide + FMNH₂ + NADH + O₂ = 2′-hydroxybiphenyl-2-sulfinate + H₂O + FMN + NAD⁺ + H⁺ (overall reaction)
(1a) FMNH₂ + O₂ = FMN-N⁵-peroxide
(1b) dibenzothiophene-5,5-dioxide + FMN-N⁵-peroxide = 2′-hydroxybiphenyl-2-sulfinate + FMN-N⁵-oxide
(1c) FMN-N⁵-oxide + NADH = FMN + H₂O + NAD⁺ + H⁺ (spontaneous)

Glossary:

dibenzothiophene-5,5-dioxide = dibenzothiophene sulfone

Other name(s):

dszA (gene name)

Systematic name:

dibenzothiophene-5,5-dioxide,FMNH₂:oxygen oxidoreductase

Comments:

This bacterial enzyme catalyses a step in the desulfurization pathway of dibenzothiophenes. The enzyme forms a two-component system with a dedicated NADH-dependent FMN reductase (EC 1.5.1.42) encoded by the dszD gene, which also interacts with EC 1.14.14.21, dibenzothiophene monooxygenase. The flavin-N⁵-oxide that is formed by the enzyme reacts spontaneously with NADH to give oxidized flavin, releasing a water molecule.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

References:

1.	Gray, K.A., Pogrebinsky, O.S., Mrachko, G.T., Xi, L., Monticello, D.J. and Squires, C.H. Molecular mechanisms of biocatalytic desulfurization of fossil fuels. Nat. Biotechnol. 14 (1996) 1705–1709. [DOI] [PMID: 9634856]
2.	Ohshiro, T., Kojima, T., Torii, K., Kawasoe, H. and Izumi, Y. Purification and characterization of dibenzothiophene (DBT) sulfone monooxygenase, an enzyme involved in DBT desulfurization, from Rhodococcus erythropolis D-1. J. Biosci. Bioeng. 88 (1999) 610–616. [DOI] [PMID: 16232672]
3.	Konishi, J., Ishii, Y., Onaka, T., Ohta, Y., Suzuki, M. and Maruhashi, K. Purification and characterization of dibenzothiophene sulfone monooxygenase and FMN-dependent NADH oxidoreductase from the thermophilic bacterium Paenibacillus sp. strain A11-2. J. Biosci. Bioeng. 90 (2000) 607–613. [DOI] [PMID: 16232919]
4.	Ohshiro, T., Ishii, Y., Matsubara, T., Ueda, K., Izumi, Y., Kino, K. and Kirimura, K. Dibenzothiophene desulfurizing enzymes from moderately thermophilic bacterium Bacillus subtilis WU-S₂B: purification, characterization and overexpression. J. Biosci. Bioeng. 100 (2005) 266–273. [DOI] [PMID: 16243275]
5.	Adak, S. and Begley, T.P. Dibenzothiophene catabolism proceeds via a flavin-N⁵-oxide intermediate. J. Am. Chem. Soc. 138 (2016) 6424–6426. [PMID: 27120486]
6.	Adak, S. and Begley, T.P. Flavin-N⁵-oxide: A new, catalytic motif in flavoenzymology. Arch. Biochem. Biophys. 632 (2017) 4–10. [PMID: 28784589]
7.	Matthews, A., Saleem-Batcha, R., Sanders, J.N., Stull, F., Houk, K.N. and Teufel, R. Aminoperoxide adducts expand the catalytic repertoire of flavin monooxygenases. Nat. Chem. Biol. 16 (2020) 556–563. [DOI] [PMID: 32066967]

[EC 1.14.14.22 created 2016, modified 2019]

1.14.14.23

Accepted name:

cholesterol 7α-monooxygenase

Reaction:

cholesterol + [reduced NADPH—hemoprotein reductase] + O₂ = 7α-hydroxycholesterol + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of cholesterol catabolism (rings A, B and C), click here

Other name(s):

cholesterol 7α-hydroxylase; CYP7A1 (gene name)

Systematic name:

cholesterol,NADPH—hemoprotein reductase:oxygen oxidoreductase (7α-hydroxylating)

Comments:

A P-450 heme-thiolate liver protein that catalyses the first step in the biosynthesis of bile acids. The direct electron donor to the enzyme is EC 1.6.2.4, NADPH—hemoprotein reductase.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 9037-53-0

References:

1.	Mitton, J.R., Scholan, N.A. and Boyd, G.S. The oxidation of cholesterol in rat liver sub-cellular particles. The cholesterol-7α-hydroxylase enzyme system. Eur. J. Biochem. 20 (1971) 569–579. [DOI] [PMID: 4397276]
2.	Boyd, G.S., Grimwade, A.M. and Lawson, M.E. Studies on rat-liver microsomal cholesterol 7α-hydroxylase. Eur. J. Biochem. 37 (1973) 334–340. [DOI] [PMID: 4147676]
3.	Ogishima, T., Deguchi, S. and Okuda, K. Purification and characterization of cholesterol 7α-hydroxylase from rat liver microsomes. J. Biol. Chem. 262 (1987) 7646–7650. [PMID: 3584134]
4.	Nguyen, L.B., Shefer, S., Salen, G., Ness, G., Tanaka, R.D., Packin, V., Thomas, P., Shore, V. and Batta, A. Purification of cholesterol 7 α-hydroxylase from human and rat liver and production of inhibiting polyclonal antibodies. J. Biol. Chem. 265 (1990) 4541–4546. [PMID: 2106520]
5.	Nguyen, L.B., Shefer, S., Salen, G., Chiang, J.Y. and Patel, M. Cholesterol 7α-hydroxylase activities from human and rat liver are modulated in vitro posttranslationally by phosphorylation/dephosphorylation. Hepatology 24 (1996) 1468–1474. [DOI] [PMID: 8938182]

[EC 1.14.14.23 created 1976 as EC 1.14.13.17, transferred 2016 to EC 1.14.14.23]

1.14.14.24

Accepted name:

vitamin D 25-hydroxylase

Reaction:

calciol + O₂ + [reduced NADPH—hemoprotein reductase] = calcidiol + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of calciferol biosynthesis, click here

Glossary:

calciol = cholecalciferol = vitamin D₃ = (3S,5Z,7E)-9,10-seco-5,7,10(19)-cholestatriene-3-ol
calcidiol = 25-hydroxyvitamin D₃ = (3S,5Z,7E)-9,10-seco-5,7,10(19)-cholestatriene-3,25-diol

Other name(s):

vitamin D₂ 25-hydroxylase; vitamin D₃ 25-hydroxylase; CYP2R1

Systematic name:

calciol,NADPH—hemoprotein reductase:oxygen oxidoreductase (25-hydroxylating)

Comments:

A microsomal enzyme isolated from human and mouse liver that bioactivates vitamin D₃. While multiple isoforms (CYP27A1, CYP2J2/3, CYP3A4, CYP2D25 and CYP2C11) are able to catalyse the reaction in vitro, only CYP2R1 is thought to catalyse the reaction in humans in vivo [4]. The direct electron donor to the enzyme is EC 1.6.2.4, NADPH—hemoprotein reductase.

Links to other databases:

References:

1.	Cheng, J.B., Motola, D.L., Mangelsdorf, D.J. and Russell, D.W. De-orphanization of cytochrome P450 2R1: a microsomal vitamin D 25-hydroxilase. J. Biol. Chem. 278 (2003) 38084–38093. [DOI] [PMID: 12867411]
2.	Shinkyo, R., Sakaki, T., Kamakura, M., Ohta, M. and Inouye, K. Metabolism of vitamin D by human microsomal CYP2R1. Biochem. Biophys. Res. Commun. 324 (2004) 451–457. [DOI] [PMID: 15465040]
3.	Strushkevich, N., Usanov, S.A., Plotnikov, A.N., Jones, G. and Park, H.W. Structural analysis of CYP2R1 in complex with vitamin D₃. J. Mol. Biol. 380 (2008) 95–106. [DOI] [PMID: 18511070]
4.	Zhu, J. and DeLuca, H.F. Vitamin D 25-hydroxylase - Four decades of searching, are we there yet? Arch. Biochem. Biophys. 523 (2012) 30–36. [DOI] [PMID: 22310641]

[EC 1.14.14.24 created 2012 as EC 1.14.13.159, transferred 2016 to EC 1.14.14.24]

1.14.14.25

Accepted name:

cholesterol 24-hydroxylase

Reaction:

cholesterol + [reduced NADPH—hemoprotein reductase] + O₂ = (24S)-cholest-5-ene-3β,24-diol + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of cholic acid biosynthesis (sidechain), click here

Glossary:

cholesterol = cholest-5-en-3β-ol
(24S)-24-hydroxycholesterol = (24S)-cholest-5-ene-3β,24-diol

Other name(s):

cholesterol 24-monooxygenase; CYP46; CYP46A1; cholesterol 24S-hydroxylase; cytochrome P450 46A1

Systematic name:

cholesterol,NADPH—hemoprotein reductase:oxygen oxidoreductase (24-hydroxylating)

Comments:

A P-450 heme-thiolate protein. The enzyme can also produce 25-hydroxycholesterol. In addition, it can further hydroxylate the product to 24,25-dihydroxycholesterol and 24,27-dihydroxycholesterol [2]. This reaction is the first step in the enzymic degradation of cholesterol in the brain as hydroxycholesterol can pass the blood—brain barrier whereas cholesterol cannot [3]. The direct electron donor to the enzyme is EC 1.6.2.4, NADPH—hemoprotein reductase [3].

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 50812-30-1, 213327-78-7

References:

1.	Lund, E.G., Guileyardo, J.M. and Russell, D.W. cDNA cloning of cholesterol 24-hydroxylase, a mediator of cholesterol homeostasis in the brain. Proc. Natl. Acad. Sci. USA 96 (1999) 7238–7243. [DOI] [PMID: 10377398]
2.	Bogdanovic, N., Bretillon, L., Lund, E.G., Diczfalusy, U., Lannfelt, L., Winblad, B., Russell, D.W. and Björkhem, I. On the turnover of brain cholesterol in patients with Alzheimer's disease. Abnormal induction of the cholesterol-catabolic enzyme CYP46 in glial cells. Neurosci. Lett. 314 (2001) 45–48. [DOI] [PMID: 11698143]
3.	Mast, N., Norcross, R., Andersson, U., Shou, M., Nakayama, K., Bjorkhem, I. and Pikuleva, I.A. Broad substrate specificity of human cytochrome P₄₅₀ 46A1 which initiates cholesterol degradation in the brain. Biochemistry 42 (2003) 14284–14292. [DOI] [PMID: 14640697]
4.	Lund, E.G., Xie, C., Kotti, T., Turley, S.D., Dietschy, J.M. and Russell, D.W. Knockout of the cholesterol 24-hydroxylase gene in mice reveals a brain-specific mechanism of cholesterol turnover. J. Biol. Chem. 278 (2003) 22980–22988. [DOI] [PMID: 12686551]
5.	Russell, D.W. The enzymes, regulation, and genetics of bile acid synthesis. Annu. Rev. Biochem. 72 (2003) 137–174. [DOI] [PMID: 12543708]

[EC 1.14.14.25 created 2005 as EC 1.14.13.98, transferred 2016 to EC 1.14.14.25]

1.14.14.26

Accepted name:

24-hydroxycholesterol 7α-hydroxylase

Reaction:

(24S)-cholest-5-ene-3β,24-diol + [reduced NADPH—hemoprotein reductase] + O₂ = (24S)-cholest-5-ene-3β,7α,24-triol + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of cholesterol catabolism (rings a, B and c), click here

Glossary:

(24S)-cholest-5-ene-3β,24-diol = (24S)-24-hydroxycholesterol

Other name(s):

24-hydroxycholesterol 7α-monooxygenase; CYP39A1; CYP39A1 oxysterol 7α-hydroxylase

Systematic name:

(24S)-cholest-5-ene-3β,24-diol,NADPH—hemoprotein reductase:oxygen oxidoreductase (7α-hydroxylating)

Comments:

A P-450 heme-thiolate protein that is found in liver microsomes and in ciliary non-pigmented epithelium [2]. The enzyme is specific for (24S)-cholest-5-ene-3β,24-diol, which is formed mostly in the brain by EC 1.14.14.25, cholesterol 24-hydroxylase. The direct electron donor to the enzyme is EC 1.6.2.4, NADPH—hemoprotein reductase.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 288309-90-0

References:

1.	Li-Hawkins, J., Lund, E.G., Bronson, A.D. and Russell, D.W. Expression cloning of an oxysterol 7α-hydroxylase selective for 24-hydroxycholesterol. J. Biol. Chem. 275 (2000) 16543–16549. [DOI] [PMID: 10748047]
2.	Ikeda, H., Ueda, M., Ikeda, M., Kobayashi, H. and Honda, Y. Oxysterol 7alpha-hydroxylase (CYP39A1) in the ciliary nonpigmented epithelium of bovine eye. Lab. Invest. 83 (2003) 349–355. [PMID: 12649335]
3.	Russell, D.W. The enzymes, regulation, and genetics of bile acid synthesis. Annu. Rev. Biochem. 72 (2003) 137–174. [DOI] [PMID: 12543708]

[EC 1.14.14.26 created 2005 as EC 1.14.13.99, transferred 2016 to EC 1.14.14.26]

1.14.14.27

Accepted name:

resorcinol 4-hydroxylase (FADH₂)

Reaction:

resorcinol + FADH₂ + O₂ = hydroxyquinol + FAD + H₂O

Glossary:

resorcinol = benzene-1,3-diol
hydroxyquinol = benzene-1,2,4-triol

Other name(s):

graA (gene name)

Systematic name:

resorcinol,FADH₂:oxygen oxidoreductase (4-hydroxylating)

Comments:

The enzyme, characterized from the bacterium Rhizobium sp. strain MTP-10005, uses FADH₂ as a substrate rather than a cofactor. FADH₂ is provided by a dedicated EC 1.5.1.36, flavin reductase (NADH). The enzyme participates in the degradation of γ-resorcylate and resorcinol. cf. EC 1.14.13.220, resorcinol 4-hydroxylase (NADH), and EC 1.14.13.219, resorcinol 4-hydroxylase (NADPH).

Links to other databases:

References:

1.	Ohta, Y. and Ribbons, D.W. Bacterial metabolism of resorcinylic compounds: purification and properties of orcinol hydroxylase and resorcinol hydroxylase from Pseudomonas putida ORC. Eur. J. Biochem. 61 (1976) 259–269. [DOI] [PMID: 1280]
2.	Yoshida, M., Oikawa, T., Obata, H., Abe, K., Mihara, H. and Esaki, N. Biochemical and genetic analysis of the γ-resorcylate (2,6-dihydroxybenzoate) catabolic pathway in Rhizobium sp. strain MTP-10005: identification and functional analysis of its gene cluster. J. Bacteriol. 189 (2007) 1573–1581. [DOI] [PMID: 17158677]

[EC 1.14.14.27 created 2016]

1.14.14.28

Accepted name:

long-chain alkane monooxygenase

Reaction:

a long-chain alkane + FMNH₂ + O₂ = a long-chain primary alcohol + FMN + H₂O

Systematic name:

long-chain-alkane,FMNH₂:oxygen oxidoreductase

Comments:

The enzyme, characterized from the bacterium Geobacillus thermodenitrificans NG80-2, is capable of converting alkanes ranging from C₁₅ to C₃₆ into their corresponding primary alcohols [1,2]. The FMNH₂ cofactor is provided by an FMN reductase [3].

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

References:

1.	Feng, L., Wang, W., Cheng, J., Ren, Y., Zhao, G., Gao, C., Tang, Y., Liu, X., Han, W., Peng, X., Liu, R. and Wang, L. Genome and proteome of long-chain alkane degrading Geobacillus thermodenitrificans NG80-2 isolated from a deep-subsurface oil reservoir. Proc. Natl. Acad. Sci. USA 104 (2007) 5602–5607. [DOI] [PMID: 17372208]
2.	Li, L., Liu, X., Yang, W., Xu, F., Wang, W., Feng, L., Bartlam, M., Wang, L. and Rao, Z. Crystal structure of long-chain alkane monooxygenase (LadA) in complex with coenzyme FMN: unveiling the long-chain alkane hydroxylase. J. Mol. Biol. 376 (2008) 453–465. [DOI] [PMID: 18164311]
3.	Dong, Y., Yan, J., Du, H., Chen, M., Ma, T. and Feng, L. Engineering of LadA for enhanced hexadecane oxidation using random- and site-directed mutagenesis. Appl. Microbiol. Biotechnol. 94 (2012) 1019–1029. [DOI] [PMID: 22526792]

[EC 1.14.14.28 created 2016]

1.14.14.29

Accepted name:

25/26-hydroxycholesterol 7α-hydroxylase

Reaction:

(1) cholest-5-ene-3β,25-diol + [reduced NADPH—hemoprotein reductase] + O₂ = cholest-5-ene-3β,7α,25-triol + [oxidized NADPH—hemoprotein reductase] + H₂O
(2) (25R)-cholest-5-ene-3β,26-diol + [reduced NADPH—hemoprotein reductase] + O₂ = (25R)-cholest-5-ene-3β,7α,26-triol + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of cholesterol catabolism (rings a, B and c), click here

Other name(s):

25-hydroxycholesterol 7α-monooxygenase; CYP7B1; CYP7B1 oxysterol 7α-hydroxylase; 27-hydroxycholesterol 7-monooxygenase; 27-hydroxycholesterol 7α-hydroxylase; cholest-5-ene-3β,25-diol,NADPH:oxygen oxidoreductase (7α-hydroxylating); 25-hydroxycholesterol 7α-hydroxylase

Systematic name:

cholest-5-ene-3β,25/26-diol,[NADPH—hemoprotein reductase]:oxygen oxidoreductase (7α-hydroxylating)

Comments:

A P-450 (heme-thiolate) protein. Unlike EC 1.14.14.26, 24-hydroxycholesterol 7α-monooxygenase, which is specific for its oxysterol substrate, this enzyme can also metabolize the oxysterols 24,25-epoxycholesterol, 22-hydroxycholesterol and 24-hydroxycholesterol, but to a lesser extent [2]. The direct electron donor to the enzyme is EC 1.6.2.4, NADPH—hemoprotein reductase.

Links to other databases:

BRENDA, EXPASY, Gene, 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. [PMID: 8496664]
2.	Toll, A., Wikvall, K., Sudjana-Sugiaman, E., Kondo, K.H. and Björkhem, I. 7α hydroxylation of 25-hydroxycholesterol in liver microsomes. Evidence that the enzyme involved is different from cholesterol 7α-hydroxylase. Eur. J. Biochem. 224 (1994) 309–316. [DOI] [PMID: 7925343]
3.	Li-Hawkins, J., Lund, E.G., Bronson, A.D. and Russell, D.W. Expression cloning of an oxysterol 7α-hydroxylase selective for 24-hydroxycholesterol. J. Biol. Chem. 275 (2000) 16543–16549. [DOI] [PMID: 10748047]
4.	Ren, S., Marques, D., Redford, K., Hylemon, P.B., Gil, G., Vlahcevic, Z.R. and Pandak, W.M. Regulation of oxysterol 7α-hydroxylase (CYP7B1) in the rat. Metabolism 52 (2003) 636–642. [DOI] [PMID: 12759897]
5.	Russell, D.W. The enzymes, regulation, and genetics of bile acid synthesis. Annu. Rev. Biochem. 72 (2003) 137–174. [DOI] [PMID: 12543708]

[EC 1.14.14.29 created 2005 as EC 1.14.13.100, modified 2013 (EC 1.14.13.60 created 1999, incorporated 2013), transferred 2016 to EC 1.14.14.29]

1.14.14.30

Accepted name:

isobutylamine N-monooxygenase

Reaction:

(1) 2-methylpropan-1-amine + FADH₂ + O₂ = N-(2-methylpropyl)hydroxylamine + FAD + H₂O
(2) 2-methylpropan-1-amine + FMNH₂ + O₂ = N-(2-methylpropyl)hydroxylamine + FMN + H₂O

Glossary:

2-methylpropan-1-amine = isobutylamine
N-(2-methylpropyl)hydroxylamine = N-hydroxy-2-methylpropan-1-amine = isobutylhydroxylamine

Other name(s):

vlmH (gene name)

Systematic name:

2-methylpropan-1-amine,FADH₂:O₂ N-oxidoreductase

Comments:

The enzyme, characterized from the bacterium Streptomyces viridifaciens, is part of a two component system that also includes a flavin reductase, which provides reduced flavin mononucleotide for this enzyme. The enzyme, which is involved in the biosynthesis of the azoxy antibiotic valanimycin, has a similar activity with either FMNH₂ or FADH₂. It exhibits broad specificity, and also accepts propan-1-amine, butan-1-amine, butan-2-amine and benzylamine.

Links to other databases:

References:

1.	Parry, R.J. and Li, W. Purification and characterization of isobutylamine N-hydroxylase from the valanimycin producer Streptomyces viridifaciens MG456-hF10. Arch. Biochem. Biophys. 339 (1997) 47–54. [DOI] [PMID: 9056232]
2.	Parry, R.J., Li, W. and Cooper, H.N. Cloning, analysis, and overexpression of the gene encoding isobutylamine N-hydroxylase from the valanimycin producer, Streptomyces viridifaciens. J. Bacteriol. 179 (1997) 409–416. [DOI] [PMID: 8990292]
3.	Parry, R.J. and Li, W. An NADPH:FAD oxidoreductase from the valanimycin producer, Streptomyces viridifaciens. Cloning, analysis, and overexpression. J. Biol. Chem. 272 (1997) 23303–23311. [DOI] [PMID: 9287340]

[EC 1.14.14.30 created 2016, modified 2017]

1.14.14.31

Accepted name:

ipsdienol synthase

Reaction:

myrcene + [reduced NADPH—hemoprotein reductase] + O₂ = (R)-ipsdienol + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of acyclic monoterpenoid biosynthesis, click here

Glossary:

myrcene = 7-methyl-3-methyleneocta-1,6-diene
ipsdienol = 2-methyl-6-methyleneocta-2,7-dien-4-ol

Other name(s):

myrcene hydroxylase; CYP9T2; CYP9T3

Systematic name:

myrcene,NADPH—hemoprotein reductase:O₂ oxidoreductase (hydroxylating)

Comments:

A cytochrome P-450 heme-thiolate protein. Involved in the insect aggregation pheromone production. Isolated from the pine engraver beetle, Ips pini. A small amount of (S)-ipsdienol is also formed. In vitro it also hydroxylated (+)- and (–)-α-pinene, 3-carene, and (+)-limonene, but not α-phellandrene, (–)-β-pinene, γ-terpinene, or terpinolene.

Links to other databases:

References:

1.	Sandstrom, P., Welch, W.H., Blomquist, G.J. and Tittiger, C. Functional expression of a bark beetle cytochrome P450 that hydroxylates myrcene to ipsdienol. Insect Biochem. Mol. Biol. 36 (2006) 835–845. [DOI] [PMID: 17046597]
2.	Song, M., Kim, A.C., Gorzalski, A.J., MacLean, M., Young, S., Ginzel, M.D., Blomquist, G.J. and Tittiger, C. Functional characterization of myrcene hydroxylases from two geographically distinct Ips pini populations. Insect Biochem. Mol. Biol. 43 (2013) 336–343. [DOI] [PMID: 23376633]

[EC 1.14.14.31 created 2015 as EC 1.14.13.207, transferred 2016 to EC 1.14.14.31]

1.14.14.32

Accepted name:

17α-hydroxyprogesterone deacetylase

Reaction:

(1) 17α-hydroxyprogesterone + [reduced NADPH—hemoprotein reductase] + O₂ = androstenedione + acetate + [oxidized NADPH—hemoprotein reductase] + H₂O
(2) 17α-hydroxypregnenolone + [reduced NADPH—hemoprotein reductase] + O₂ = 3β-hydroxyandrost-5-en-17-one + acetate + [oxidized NADPH—hemoprotein reductase] + H₂O

Glossary:

androstenedione = androst-4-ene-3,17-dione

Other name(s):

C-17/C-20 lyase; 17α-hydroxyprogesterone acetaldehyde-lyase; CYP17; CYP17A1 (gene name); 17α-hydroxyprogesterone 17,20-lyase

Systematic name:

17α-hydroxyprogesterone,NADPH—hemoprotein reductase:oxygen oxidoreductase (17α-hydroxylating, acetate-releasing)

Comments:

A microsomal cytochrome P-450 (heme-thiolate) protein that catalyses two independent reactions at the same active site - the 17-hydroxylation of pregnenolone and progesterone, which is part of glucocorticoid hormones biosynthesis (EC 1.14.14.19), and the conversion of the 17-hydroxylated products via a 17,20-lyase reaction to form androstenedione and 3β-hydroxyandrost-5-en-17-one, leading to sex hormone biosynthesis. The activity of this reaction is dependent on the allosteric interaction of the enzyme with cytochrome b₅ without any transfer of electrons from the cytochrome [2,4]. The enzymes from different organisms differ in their substrate specificity. While the enzymes from pig, hamster, and rat accept both 17α-hydroxyprogesterone and 17α-hydroxypregnenolone, the enzymes from human, bovine, sheep, goat, and bison do not accept the former, and the enzyme from guinea pig does not accept the latter [1].

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 62213-24-5

References:

1.	Gilep, A.A., Estabrook, R.W. and Usanov, S.A. Molecular cloning and heterologous expression in E. coli of cytochrome P45017α. Comparison of structural and functional properties of substrate-specific cytochromes P450 from different species. Biochemistry (Mosc.) 68 (2003) 86–98. [PMID: 12693981]
2.	Auchus, R.J., Lee, T.C. and Miller, W.L. Cytochrome b₅ augments the 17,20-lyase activity of human P450c17 without direct electron transfer. J. Biol. Chem. 273 (1998) 3158–3165. [DOI] [PMID: 9452426]
3.	Mak, P.J., Gregory, M.C., Denisov, I.G., Sligar, S.G. and Kincaid, J.R. Unveiling the crucial intermediates in androgen production. Proc. Natl. Acad. Sci. USA 112 (2015) 15856–15861. [DOI] [PMID: 26668369]
4.	Simonov, A.N., Holien, J.K., Yeung, J.C., Nguyen, A.D., Corbin, C.J., Zheng, J., Kuznetsov, V.L., Auchus, R.J., Conley, A.J., Bond, A.M., Parker, M.W., Rodgers, R.J. and Martin, L.L. Mechanistic scrutiny identifies a kinetic role for cytochrome b₅ regulation of human cytochrome P450c17 (CYP17A1, P450 17A1). PLoS One 10:e0141252 (2015). [DOI] [PMID: 26587646]
5.	Bhatt, M.R., Khatri, Y., Rodgers, R.J. and Martin, L.L. Role of cytochrome b₅ in the modulation of the enzymatic activities of cytochrome P450 17α-hydroxylase/17,20-lyase (P450 17A1). J. Steroid Biochem. Mol. Biol. (2016) . [DOI] [PMID: 26976652]

[EC 1.14.14.32 created 1976 as EC 4.1.2.30, transferred 2016 to EC 1.14.14.32]

1.14.14.33

Accepted name:

ethylenediaminetetraacetate monooxygenase

Reaction:

ethylenediaminetetraacetate + 2 FMNH₂ + 2 O₂ = ethylenediamine-N,N′-diacetate + 2 glyoxylate + 2 FMN + 2 H₂O (overall reaction)
(1a) ethylenediaminetetraacetate + FMNH₂ + O₂ = ethylenediaminetriacetate + glyoxylate + FMN + H₂O
(1b) ethylenediaminetriacetate + FMNH₂ + O₂ = ethylenediamine-N,N′-diacetate + glyoxylate + FMN + H₂O

Glossary:

ethylenediaminetetraacetate = EDTA

Systematic name:

ethylenediaminetetraacetate,FMNH₂:O₂ oxidoreductase (glyoxylate-forming)

Comments:

The enzyme is part of a two component system that also includes EC 1.5.1.42, FMN reductase (NADH), which provides reduced flavin mononucleotide for this enzyme. It acts on EDTA only when it is complexed with divalent cations such as Mg²⁺, Zn²⁺, Mn²⁺, Co²⁺, or Cu²⁺. While the enzyme has a substrate overlap with EC 1.14.14.10, nitrilotriacetate monooxygenase, it has a much wider substrate range, which includes nitrilotriacetate (NTA) and diethylenetriaminepentaacetate (DTPA) in addition to EDTA.

Links to other databases:

References:

1.	Witschel, M., Nagel, S. and Egli, T. Identification and characterization of the two-enzyme system catalyzing oxidation of EDTA in the EDTA-degrading bacterial strain DSM 9103. J. Bacteriol. 179 (1997) 6937–6943. [DOI] [PMID: 9371437]
2.	Payne, J.W., Bolton, H., Jr., Campbell, J.A. and Xun, L. Purification and characterization of EDTA monooxygenase from the EDTA-degrading bacterium BNC1. J. Bacteriol. 180 (1998) 3823–3827. [PMID: 9683478]
3.	Bohuslavek, J., Payne, J.W., Liu, Y., Bolton, H., Jr. and Xun, L. Cloning, sequencing, and characterization of a gene cluster involved in EDTA degradation from the bacterium BNC1. Appl. Environ. Microbiol. 67 (2001) 688–695. [DOI] [PMID: 11157232]

[EC 1.14.14.33 created 2016]

1.14.14.34

Accepted name:

methanesulfonate monooxygenase (FMNH₂)

Reaction:

methanesulfonate + FMNH₂ + O₂ = formaldehyde + FMN + sulfite + H₂O

Glossary:

methanesulfonate = CH₃-SO₃^-
formaldehyde = H-CHO

Other name(s):

msuD (gene name); ssuD (gene name)

Systematic name:

methanesulfonate,FMNH₂:oxygen oxidoreductase

Comments:

The enzyme, characterized from Pseudomonas strains, allows the organisms to utilize methanesulfonate as their sulfur source. It acts in combination with a dedicated NADH-dependent FMN reductase (EC 1.5.1.42), which provides it with reduced FMN. cf. EC 1.14.13.111, methanesulfonate monooxygenase (NADH).

Links to other databases:

BRENDA, EAWAG-BBD, EXPASY, KEGG, MetaCyc, PDB

References:

1.	Kertesz, M.A., Schmidt-Larbig, K. and Wuest, T. A novel reduced flavin mononucleotide-dependent methanesulfonate sulfonatase encoded by the sulfur-regulated msu operon of Pseudomonas aeruginosa. J. Bacteriol. 181 (1999) 1464–1473. [PMID: 10049377]
2.	Endoh, T., Kasuga, K., Horinouchi, M., Yoshida, T., Habe, H., Nojiri, H. and Omori, T. Characterization and identification of genes essential for dimethyl sulfide utilization in Pseudomonas putida strain DS1. Appl. Microbiol. Biotechnol. 62 (2003) 83–91. [DOI] [PMID: 12835925]

[EC 1.14.14.34 created 2016]

1.14.14.35

Accepted name:

dimethylsulfone monooxygenase

Reaction:

dimethyl sulfone + FMNH₂ + O₂ = methanesulfinate + formaldehyde + FMN + H₂O

Other name(s):

sfnG (gene name)

Systematic name:

dimethyl sulfone,FMNH₂:oxygen oxidoreductase

Comments:

The enzyme, characterized from Pseudomonas spp., is involved in a dimethyl sulfide degradation pathway. It is dependent on NAD(P)H-dependent FMN reductase (EC 1.5.1.38, EC 1.5.1.39, or EC 1.5.1.42), which provides it with reduced FMN. The product, methanesulfinate, is oxidized spontaneously to methanesulfonate in the presence of dioxygen and FMNH₂.

Links to other databases:

References:

1.	Endoh, T., Habe, H., Nojiri, H., Yamane, H. and Omori, T. The σ⁵⁴-dependent transcriptional activator SfnR regulates the expression of the Pseudomonas putida sfnFG operon responsible for dimethyl sulphone utilization. Mol. Microbiol. 55 (2005) 897–911. [DOI] [PMID: 15661012]
2.	Wicht, D.K. The reduced flavin-dependent monooxygenase SfnG converts dimethylsulfone to methanesulfinate. Arch. Biochem. Biophys. 604 (2016) 159–166. [DOI] [PMID: 27392454]

[EC 1.14.14.35 created 2016]

1.14.14.36

Accepted name:

tyrosine N-monooxygenase

Reaction:

L-tyrosine + 2 O₂ + 2 [reduced NADPH—hemoprotein reductase] = (E)-[4-hydroxyphenylacetaldehyde oxime] + 2 [oxidized NADPH—hemoprotein reductase] + CO₂ + 3 H₂O (overall reaction)
(1a) L-tyrosine + O₂ + [reduced NADPH—hemoprotein reductase] = N-hydroxy-L-tyrosine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1b) N-hydroxy-L-tyrosine + O₂ + [reduced NADPH—hemoprotein reductase] = N,N-dihydroxy-L-tyrosine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1c) N,N-dihydroxy-L-tyrosine = (E)-[4-hydroxyphenylacetaldehyde oxime] + CO₂ + H₂O

For diagram of dhurrin biosynthesis, click here

Other name(s):

tyrosine N-hydroxylase; CYP79A1

Systematic name:

L-tyrosine,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)

Comments:

A cytochrome P-450 (heme-thiolate) protein. The enzyme from Sorghum is involved in the biosynthesis of the cyanogenic glucoside dhurrin. In Sinapis alba (white mustard) the enzyme is involved in the biosynthesis of the glucosinolate sinalbin.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, CAS registry number: 159447-19-5

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-450TYR 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. [DOI] [PMID: 7876084]
3.	Bennett, R.N., Kiddle, G. and Wallsgrove, R.M. Involvement of cytochrome P450 in glucosinolate biosynthesis in white mustard (a biochemical anomaly). Plant Physiol. 114 (1997) 1283–1291. [PMID: 12223771]
4.	Kahn, R.A., Fahrendorf, T., Halkier, B.A. and Møller, B.L. Substrate specificity of the cytochrome P450 enzymes CYP79A1 and CYP71E1 involved in the biosynthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor (L.) Moench. Arch. Biochem. Biophys. 363 (1999) 9–18. [DOI] [PMID: 10049494]
5.	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]
6.	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]
7.	Busk, P.K. and Møller, B.L. Dhurrin synthesis in sorghum is regulated at the transcriptional level and induced by nitrogen fertilization in older plants. Plant Physiol. 129 (2002) 1222–1231. [DOI] [PMID: 12114576]
8.	Kristensen, C., Morant, M., Olsen, C.E., Ekstrøm, C.T., Galbraith, D.W., Møller, B.L. and Bak, S. Metabolic engineering of dhurrin in transgenic Arabidopsis plants with marginal inadvertent effects on the metabolome and transcriptome. Proc. Natl. Acad. Sci. USA 102 (2005) 1779–1784. [DOI] [PMID: 15665094]
9.	Clausen, M., Kannangara, R.M., Olsen, C.E., Blomstedt, C.K., Gleadow, R.M., Jørgensen, K., Bak, S., Motawie, M.S. and Møller, B.L. The bifurcation of the cyanogenic glucoside and glucosinolate biosynthetic pathways. Plant J. 84 (2015) 558–573. [DOI] [PMID: 26361733]

[EC 1.14.14.36 created 1992 as EC 1.14.13.41, modified 2001, modified 2005, transferred 2016 to EC 1.14.14.36]

1.14.14.37

Accepted name:

4-hydroxyphenylacetaldehyde oxime monooxygenase

Reaction:

(E)-4-hydroxyphenylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + O₂ = (S)-4-hydroxymandelonitrile + [oxidized NADPH—hemoprotein reductase] + 2 H₂O (overall reaction)
(1a) (E)-4-hydroxyphenylacetaldehyde oxime = (Z)-4-hydroxyphenylacetaldehyde oxime
(1b) (Z)-4-hydroxyphenylacetaldehyde oxime = 4-hydroxyphenylacetonitrile + H₂O
(1c) 4-hydroxyphenylacetonitrile + [reduced NADPH—hemoprotein reductase] + O₂ = (S)-4-hydroxymandelonitrile + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of dhurrin biosynthesis, click here

Glossary:

(S)-4-hydroxymandelonitrile = (2S)-hydroxy(4-hydroxyphenyl)acetonitrile

Other name(s):

4-hydroxybenzeneacetaldehyde oxime monooxygenase; cytochrome P450II-dependent monooxygenase; NADPH-cytochrome P450 reductase (CYP71E1); CYP71E1; 4-hydroxyphenylacetaldehyde oxime,NADPH:oxygen oxidoreductase

Systematic name:

(E)-4-hydroxyphenylacetaldehyde oxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase

Comments:

This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of the cyanogenic glucoside dhurrin in sorghum. It catalyses three different activities - isomerization of the (E) isomer to the (Z) isomer, dehydration, and C-hydroxylation.

Links to other databases:

References:

1.	MacFarlane, I.J., Lees, E.M. and Conn, E.E. The in vitro biosynthesis of dhurrin, the cyanogenic glycoside of Sorghum bicolor. J. Biol. Chem. 250 (1975) 4708–4713. [PMID: 237909]
2.	Shimada, M. and Conn, E.E. The enzymatic conversion of p-hydroxyphenylacetaldoxime to p-hydroxymandelonitrile. Arch. Biochem. Biophys. 180 (1977) 199–207. [DOI] [PMID: 193443]
3.	Busk, P.K. and Møller, B.L. Dhurrin synthesis in sorghum is regulated at the transcriptional level and induced by nitrogen fertilization in older plants. Plant Physiol. 129 (2002) 1222–1231. [DOI] [PMID: 12114576]
4.	Kristensen, C., Morant, M., Olsen, C.E., Ekstrøm, C.T., Galbraith, D.W., Møller, B.L. and Bak, S. Metabolic engineering of dhurrin in transgenic Arabidopsis plants with marginal inadvertent effects on the metabolome and transcriptome. Proc. Natl. Acad. Sci. USA 102 (2005) 1779–1784. [DOI] [PMID: 15665094]
5.	Clausen, M., Kannangara, R.M., Olsen, C.E., Blomstedt, C.K., Gleadow, R.M., Jørgensen, K., Bak, S., Motawie, M.S. and Møller, B.L. The bifurcation of the cyanogenic glucoside and glucosinolate biosynthetic pathways. Plant J. 84 (2015) 558–573. [DOI] [PMID: 26361733]

[EC 1.14.14.37 created 2000 as EC 1.14.13.68, modified 2005, transferred 2016 to EC 1.14.14.37]

1.14.14.38

Accepted name:

valine N-monooxygenase

Reaction:

L-valine + 2 [reduced NADPH—hemoprotein reductase] + 2 O₂ = (E)-2-methylpropanal oxime + 2 [oxidized NADPH—hemoprotein reductase] + CO₂ + 3 H₂O (overall reaction)
(1a) L-valine + [reduced NADPH—hemoprotein reductase] + O₂ = N-hydroxy-L-valine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1b) N-hydroxy-L-valine + [reduced NADPH—hemoprotein reductase] + O₂ = N,N-dihydroxy-L-valine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1c) N,N-dihydroxy-L-valine = (E)-2-methylpropanal oxime + CO₂ + H₂O

Other name(s):

CYP79D1; CYP79D2

Systematic name:

L-valine,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)

Comments:

A cytochrome P-450 (heme-thiolate) protein. This enzyme catalyses two successive N-hydroxylations of L-valine, the committed step in the biosynthesis of the cyanogenic glucoside linamarin in Manihot esculenta (cassava). The product of the two hydroxylations, N,N-dihydroxy-L-valine, is labile and undergoes dehydration and decarboxylation that produce the (E) isomer of the oxime. It is still not known whether the decarboxylation is spontaneous or catalysed by the enzyme. The enzyme can also accept L-isoleucine as substrate, with a lower activity. It is different from EC 1.14.14.39, isoleucine N-monooxygenase, which prefers L-isoleucine.

Links to other databases:

References:

Andersen, M.D., Busk, P.K., Svendsen, I. and Møller, B.L. Cytochromes P-450 from cassava (Manihot esculenta Crantz) catalyzing the first steps in the biosynthesis of the cyanogenic glucosides linamarin and lotaustralin. Cloning, functional expression in Pichia pastoris, and substrate specificity of the isolated recombinant enzymes. J. Biol. Chem. 275 (2000) 1966–1975. [DOI] [PMID: 10636899]

Forslund, K., Morant, M., Jørgensen, B., Olsen, C.E., Asamizu, E., Sato, S., Tabata, S. and Bak, S. Biosynthesis of the nitrile glucosides rhodiocyanoside A and D and the cyanogenic glucosides lotaustralin and linamarin in Lotus japonicus. Plant Physiol. 135 (2004) 71–84. [DOI] [PMID: 15122013]

[EC 1.14.14.38 created 2010 as EC 1.14.13.118, transferred 2017 to EC 1.14.14.38]

1.14.14.39

Accepted name:

isoleucine N-monooxygenase

Reaction:

L-isoleucine + 2 [reduced NADPH—hemoprotein reductase] + 2 O₂ = (1E,2S)-2-methylbutanal oxime + 2 [oxidized NADPH—hemoprotein reductase] + CO₂ + 3 H₂O (overall reaction)
(1a) L-isoleucine + [reduced NADPH—hemoprotein reductase] + O₂ = N-hydroxy-L-isoleucine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1b) N-hydroxy-L-isoleucine + [reduced NADPH—hemoprotein reductase] + O₂ = N,N-dihydroxy-L-isoleucine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1c) N,N-dihydroxy-L-isoleucine = (1E,2S)-2-methylbutanal oxime + CO₂ + H₂O (spontaneous)

Other name(s):

CYP79D3 (gene name); CYP79D4 (gene name)

Systematic name:

L-isoleucine,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)

Comments:

This cytochrome P-450 (heme-thiolate) enzyme, found in plants, catalyses two successive N-hydroxylations of L-isoleucine, the committed step in the biosynthesis of the cyanogenic glucoside lotaustralin. The product of the two hydroxylations, N,N-dihydroxy-L-isoleucine, is labile and undergoes dehydration followed by decarboxylation, producing the oxime. It is still not known whether the decarboxylation is spontaneous or catalysed by the enzyme. The enzyme can also accept L-valine, but with a lower activity. cf. EC 1.14.14.38, valine N-monooxygenase.

Links to other databases:

References:

[EC 1.14.14.39 created 2010 as EC 1.14.13.117, transferred 2017 to EC 1.14.14.39]

1.14.14.40

Accepted name:

phenylalanine N-monooxygenase

Reaction:

L-phenylalanine + 2 [reduced NADPH—hemoprotein reductase] + 2 O₂ = (E)-phenylacetaldoxime + 2 [oxidized NADPH—hemoprotein reductase] + CO₂ + 3 H₂O (overall reaction)
(1a) L-phenylalanine + [reduced NADPH—hemoprotein reductase] + O₂ = N-hydroxy-L-phenylalanine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1b) N-hydroxy-L-phenylalanine + [reduced NADPH—hemoprotein reductase] + O₂ = N,N-dihydroxy-L-phenylalanine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1c) N,N-dihydroxy-L-phenylalanine = (E)-phenylacetaldoxime + CO₂ + H₂O

Other name(s):

phenylalanine N-hydroxylase; CYP79A2 (gene name); CYP79D16 (gene name)

Systematic name:

L-phenylalanine,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)

Comments:

This cytochrome P-450 (heme-thiolate) enzyme, found in plants, catalyses two successive N-hydroxylations of L-phenylalanine, a committed step in the biosynthesis of benzylglucosinolate and the cyanogenic glucosides (R)-prunasin and (R)-amygdalin. The product of the two hydroxylations, N,N-dihydroxy-L-phenylalanine, is labile and undergoes dehydration followed by decarboxylation, producing an oxime. It is still not known whether the decarboxylation is spontaneous or catalysed by the enzyme.

Links to other databases:

References:

1.	Wittstock, U. and Halkier, B.A. Cytochrome P₄₅₀ CYP79A2 from Arabidopsis thaliana L. Catalyzes the conversion of L-phenylalanine to phenylacetaldoxime in the biosynthesis of benzylglucosinolate. J. Biol. Chem. 275 (2000) 14659–14666. [DOI] [PMID: 10799553]
2.	Yamaguchi, T., Yamamoto, K. and Asano, Y. Identification and characterization of CYP79D16 and CYP71AN24 catalyzing the first and second steps in L-phenylalanine-derived cyanogenic glycoside biosynthesis in the Japanese apricot, Prunus mume Sieb. et Zucc. Plant Mol. Biol. 86 (2014) 215–223. [DOI] [PMID: 25015725]

[EC 1.14.14.40 created 2011 as EC 1.14.13.124, transferred 2017 to EC 1.14.14.40]

1.14.14.41

Accepted name:

(E)-2-methylbutanal oxime monooxygenase

Reaction:

(1) (E)-2-methylbutanal oxime + [reduced NADPH—hemoprotein reductase] + O₂ = 2-hydroxy-2-methylbutanenitrile + [oxidized NADPH—hemoprotein reductase] + 2 H₂O (overall reaction)
(1a) (E)-2-methylbutanal oxime = (Z)-2-methylbutanal oxime
(1b) (Z)-2-methylbutanal oxime = 2-methylbutanenitrile + H₂O
(1c) 2-methylbutanenitrile + [reduced NADPH—hemoprotein reductase] + O₂ = 2-hydroxy-2-methylbutanenitrile + [oxidized NADPH—hemoprotein reductase] + H₂O
(2) (E)-2-methylpropanal oxime + [reduced NADPH—hemoprotein reductase] + O₂ = 2-hydroxy-2-methylpropanenitrile + [oxidized NADPH—hemoprotein reductase] + 2 H₂O (overall reaction)
(2a) (E)-2-methylpropanal oxime = (Z)-2-methylpropanal oxime
(2b) (Z)-2-methylpropanal oxime = 2-methylpropanenitrile + H₂O
(2c) 2-methylpropanenitrile + [reduced NADPH—hemoprotein reductase] + O₂ = 2-hydroxy-2-methylpropanenitrile + [oxidized NADPH—hemoprotein reductase] + H₂O

Other name(s):

CYP71E7 (gene name)

Systematic name:

(E)-2-methylbutanal oxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase

Comments:

This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of the cyanogenic glucosides lotaustralin and linamarin. It catalyses three different activities - isomerization of its substrate, the (E) isomer, to the (Z) isomer, dehydration, and C-hydroxylation.

Links to other databases:

References:

Jørgensen, K., Morant, A.V., Morant, M., Jensen, N.B., Olsen, C.E., Kannangara, R., Motawia, M.S., Møller, B.L. and Bak, S. Biosynthesis of the cyanogenic glucosides linamarin and lotaustralin in cassava: isolation, biochemical characterization, and expression pattern of CYP71E7, the oxime-metabolizing cytochrome P450 enzyme. Plant Physiol. 155 (2011) 282–292. [DOI] [PMID: 21045121]

[EC 1.14.14.41 created 2017]

1.14.14.42

Accepted name:

homomethionine N-monooxygenase

Reaction:

an L-polyhomomethionine + 2 [reduced NADPH—hemoprotein reductase] + 2 O₂ = an (E)-ω-(methylsulfanyl)alkanal oxime + 2 [oxidized NADPH—hemoprotein reductase] + CO₂ + 3 H₂O (overall reaction)
(1a) an L-polyhomomethionine + [reduced NADPH—hemoprotein reductase] + O₂ = an L-N-hydroxypolyhomomethionine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1b) an L-N-hydroxypolyhomomethionine + [reduced NADPH—hemoprotein reductase] + O₂ = an L-N,N-dihydroxypolyhomomethionine + [oxidized NADPH—hemoprotein reductase] + H₂O
(1c) an L-N,N-dihydroxypolyhomomethionine = an (E)-ω-(methylsulfanyl)alkanal oxime + CO₂ + H₂O

Glossary:

homomethionine = (2S)-2-amino-5-(methylsulfanyl)pentanoate
an L-polyhomomethionine = analogs of L-methionine that contain additional methylene groups in the side chain prior to the sulfur atom.

Other name(s):

CYP79F1 (gene name); CYP79F2 (gene name)

Systematic name:

L-polyhomomethionine,[NADPH—hemoprotein reductase]:oxygen oxidoreductase

Comments:

This plant cytochrome P-450 (heme thiolate) enzyme is involved in methionine-derived aliphatic glucosinolates biosynthesis. It catalyses two successive N-hydroxylations, which are followed by dehydration and decarboxylation. CYP79F1 from Arabidopsis thaliana can metabolize mono-, di-, tri-, tetra-, penta-, and hexahomomethionine to their corresponding aldoximes, while CYP79F2 from the same plant can only metabolize penta- and hexahomomethionine.

Links to other databases:

References:

1.	Hansen, C.H., Wittstock, U., Olsen, C.E., Hick, A.J., Pickett, J.A. and Halkier, B.A. Cytochrome p₄₅₀ CYP79F1 from arabidopsis catalyzes the conversion of dihomomethionine and trihomomethionine to the corresponding aldoximes in the biosynthesis of aliphatic glucosinolates. J. Biol. Chem. 276 (2001) 11078–11085. [DOI] [PMID: 11133994]
2.	Chen, S., Glawischnig, E., Jørgensen, K., Naur, P., Jorgensen, B., Olsen, C.E., Hansen, C.H., Rasmussen, H., Pickett, J.A. and Halkier, B.A. CYP79F1 and CYP79F2 have distinct functions in the biosynthesis of aliphatic glucosinolates in Arabidopsis. Plant J. 33 (2003) 923–937. [DOI] [PMID: 12609033]

[EC 1.14.14.42 created 2017]

1.14.14.43

Accepted name:

(methylsulfanyl)alkanaldoxime N-monooxygenase

Reaction:

an (E)-ω-(methylsulfanyl)alkanal oxime + [reduced NADPH—hemoprotein reductase] + glutathione + O₂ = an S-[(1E)-1-(hydroxyimino)-ω-(methylsulfanyl)alkyl]-L-glutathione + [oxidized NADPH—hemoprotein reductase] + 2 H₂O (overall reaction)
(1a) an (E)-ω-(methylsulfanyl)alkanal oxime + [reduced NADPH—hemoprotein reductase] + O₂ = a 1-(methylsulfanyl)-4-aci-nitroalkane + [oxidized NADPH—hemoprotein reductase] + H₂O
(1b) a 1-(methylsulfanyl)-4-aci-nitroalkane + glutathione = an S-[(1E)-1-(hydroxyimino)-ω-(methylsulfanyl)alkyl]-L-glutathione + H₂O

Glossary:

a 1-(methylsulfanyl)-4-aci-nitroalkane = a hydroxyoxo-λ⁵-azanylidene-ω-(methylsulfanyl)alkane

Other name(s):

CYP83A1 (gene name); (methylthio)alkanaldoxime N-monooxygenase; (E)-ω-(methylthio)alkananaldoxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)

Systematic name:

(E)-ω-(methylsulfanyl)alkananal oxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)

Comments:

This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of glucosinolates in plants. The enzyme catalyses an N-hydroxylation of the E isomer of ω-(methylsulfanyl)alkanal oximes, forming an aci-nitro intermediate that reacts non-enzymically with glutathione to produce an N-alkyl-thiohydroximate adduct, the committed precursor of glucosinolates. In the absence of a thiol compound, the enzyme is suicidal, probably due to interaction of the reactive aci-nitro intermediate with active site residues.

Links to other databases:

References:

1.	Bak, S., Tax, F.E., Feldmann, K.A., Galbraith, D.W. and Feyereisen, R. CYP83B1, a cytochrome P450 at the metabolic branch point in auxin and indole glucosinolate biosynthesis in Arabidopsis. Plant Cell 13 (2001) 101–111. [PMID: 11158532]
2.	Naur, P., Petersen, B.L., Mikkelsen, M.D., Bak, S., Rasmussen, H., Olsen, C.E. and Halkier, B.A. CYP83A1 and CYP83B1, two nonredundant cytochrome P450 enzymes metabolizing oximes in the biosynthesis of glucosinolates in Arabidopsis. Plant Physiol. 133 (2003) 63–72. [DOI] [PMID: 12970475]
3.	Clausen, M., Kannangara, R.M., Olsen, C.E., Blomstedt, C.K., Gleadow, R.M., Jørgensen, K., Bak, S., Motawie, M.S. and Møller, B.L. The bifurcation of the cyanogenic glucoside and glucosinolate biosynthetic pathways. Plant J. 84 (2015) 558–573. [DOI] [PMID: 26361733]

[EC 1.14.14.43 created 2017]

1.14.14.44

Accepted name:

phenylacetaldehyde oxime monooxygenase

Reaction:

(E)-phenylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + O₂ = (R)-mandelonitrile + [oxidized NADPH—hemoprotein reductase] + 2 H₂O (overall reaction)
(1a) (E)-phenylacetaldehyde oxime = (Z)-phenylacetaldehyde oxime
(1b) (Z)-phenylacetaldehyde oxime = phenylacetonitrile + H₂O
(1c) phenylacetonitrile + [reduced NADPH—hemoprotein reductase] + O₂ = (R)-mandelonitrile + [oxidized NADPH—hemoprotein reductase] + H₂O

Glossary:

(R)-mandelonitrile = (2R)-hydroxy(phenyl)acetonitrile

Other name(s):

CYP71AN24 (gene name)

Systematic name:

(E)-phenylacetaldehyde oxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase

Comments:

This cytochrome P-450 (heme-thiolate) enzyme is involved in the biosynthesis of the cyanogenic glucosides (R)-prunasin and (R)-amygdalin. It catalyses three different activities - isomerization of the (E) isomer to the (Z) isomer, dehydration, and C-hydroxylation.

Links to other databases:

References:

Yamaguchi, T., Yamamoto, K. and Asano, Y. Identification and characterization of CYP79D16 and CYP71AN24 catalyzing the first and second steps in L-phenylalanine-derived cyanogenic glycoside biosynthesis in the Japanese apricot, Prunus mume Sieb. et Zucc. Plant Mol. Biol. 86 (2014) 215–223. [DOI] [PMID: 25015725]

[EC 1.14.14.44 created 2017]

1.14.14.45

Accepted name:

aromatic aldoxime N-monooxygenase

Reaction:

(1) (E)-indol-3-ylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + glutathione + O₂ = S-[(E)-N-hydroxy(indol-3-yl)acetimidoyl]-L-glutathione + [oxidized NADPH—hemoprotein reductase] + 2 H₂O (overall reaction)
(1a) (E)-indol-3-ylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + O₂ = 1-(1H-indol-3-yl)-2-aci-nitroethane + [oxidized NADPH—hemoprotein reductase] + H₂O
(1b) 1-(1H-indol-3-yl)-2-aci-nitroethane + glutathione = S-[(E)-N-hydroxy(indol-3-yl)acetimidoyl]-L-glutathione + H₂O (spontaneous)
(2) (E)-phenylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + glutathione + O₂ = S-[(Z)-N-hydroxy(phenyl)acetimidoyl]-L-glutathione + [oxidized NADPH—hemoprotein reductase] + 2 H₂O (overall reaction)
(2a) (E)-phenylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + O₂ = 1-aci-nitro-2-phenylethane + [oxidized NADPH—hemoprotein reductase] + H₂O
(2b) 1-aci-nitro-2-phenylethane + glutathione = S-[(Z)-N-hydroxy(phenyl)acetimidoyl]-L-glutathione + H₂O (spontaneous)

Other name(s):

CYP83B1 (gene name)

Systematic name:

(E)-indol-3-ylacetaldoxime,[reduced NADPH—hemoprotein reductase],glutathione:oxygen oxidoreductase (oxime-hydroxylating)

Comments:

This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of glucosinolates in plants. The enzyme catalyses the N-hydroxylation of aromatic aldoximes derived from L-tryptophan, L-phenylalanine, and L-tyrosine, forming an aci-nitro intermediate that reacts non-enzymically with glutathione to produce an N-alkyl-thiohydroximate adduct, the committed precursor of glucosinolates. In the absence of glutathione, the enzyme is suicidal, probably due to interaction of the reactive aci-nitro compound with catalytic residues in the active site.

Links to other databases:

References:

1.	Bak, S., Tax, F.E., Feldmann, K.A., Galbraith, D.W. and Feyereisen, R. CYP83B1, a cytochrome P450 at the metabolic branch point in auxin and indole glucosinolate biosynthesis in Arabidopsis. Plant Cell 13 (2001) 101–111. [PMID: 11158532]
2.	Naur, P., Petersen, B.L., Mikkelsen, M.D., Bak, S., Rasmussen, H., Olsen, C.E. and Halkier, B.A. CYP83A1 and CYP83B1, two nonredundant cytochrome P450 enzymes metabolizing oximes in the biosynthesis of glucosinolates in Arabidopsis. Plant Physiol. 133 (2003) 63–72. [DOI] [PMID: 12970475]
3.	Geu-Flores, F., Møldrup, M.E., Böttcher, C., Olsen, C.E., Scheel, D. and Halkier, B.A. Cytosolic γ-glutamyl peptidases process glutathione conjugates in the biosynthesis of glucosinolates and camalexin in Arabidopsis. Plant Cell 23 (2011) 2456–2469. [DOI] [PMID: 21712415]

[EC 1.14.14.45 created 2017]

1.14.14.46

Accepted name:

pimeloyl-[acyl-carrier protein] synthase

Reaction:

a long-chain acyl-[acyl-carrier protein] + 2 reduced flavodoxin + 3 O₂ = pimeloyl-[acyl-carrier protein] + an n-alkanal + 2 oxidized flavodoxin + 3 H₂O (overall reaction)
(1a) a long-chain acyl-[acyl-carrier protein] + reduced flavodoxin + O₂ = a (7S)-7-hydroxy-long-chain-acyl-[acyl-carrier protein] + oxidized flavodoxin + H₂O
(1b) a (7S)-7-hydroxy-long-chain-acyl-[acyl-carrier protein] + reduced flavodoxin + O₂ = a (7R,8R)-7,8-dihydroxy-long-chain-acyl-[acyl-carrier protein] + oxidized flavodoxin + H₂O
(1c) a (7R,8R)-7,8-dihydroxy-long-chain-acyl-[acyl-carrier protein] + reduced flavodoxin + O₂ = a 7-oxoheptanoyl-[acyl-carrier protein] + an n-alkanal + oxidized flavodoxin + 2 H₂O
(1d) a 7-oxoheptanoyl-[acyl-carrier protein] + oxidized flavodoxin + H₂O = a pimeloyl-[acyl-carrier protein] + reduced flavodoxin + H⁺

Glossary:

a long-chain acyl-[acyl-carrier protein] = an acyl-[acyl-carrier protein] thioester where the acyl chain contains 13 to 22 carbon atoms.
palmitoyl-[acyl-carrier protein] = hexadecanoyl-[acyl-carrier protein]
pimeloyl-[acyl-carrier protein] = 6-carboxyhexanoyl-[acyl-carrier protein]

Other name(s):

bioI (gene name); P450BioI; CYP107H1

Systematic name:

acyl-[acyl-carrier protein],reduced-flavodoxin:oxygen oxidoreductase (pimeloyl-[acyl-carrier protein]-forming)

Comments:

A cytochrome P-450 (heme-thiolate) protein. The enzyme catalyses an oxidative C-C bond cleavage of long-chain acyl-[acyl-carrier protein]s of various lengths to generate pimeloyl-[acyl-carrier protein], an intermediate in the biosynthesis of biotin. The preferred substrate of the enzyme from the bacterium Bacillus subtilis is palmitoyl-[acyl-carrier protein] which then gives heptanal as the alkanal. The mechanism is similar to EC 1.14.15.6, cholesterol monooxygenase (side-chain-cleaving), followed by a hydroxylation step, which may occur spontaneously [2].

Links to other databases:

References:

1.	Stok, J.E. and De Voss, J. Expression, purification, and characterization of BioI: a carbon-carbon bond cleaving cytochrome P450 involved in biotin biosynthesis in Bacillus subtilis. Arch. Biochem. Biophys. 384 (2000) 351–360. [DOI] [PMID: 11368323]
2.	Cryle, M.J. and De Voss, J.J. Carbon-carbon bond cleavage by cytochrome p₄₅₀(BioI)(CYP107H1). Chem. Commun. (Camb.) (2004) 86–87. [DOI] [PMID: 14737344]
3.	Cryle, M.J. and Schlichting, I. Structural insights from a P450 Carrier Protein complex reveal how specificity is achieved in the P450(BioI) ACP complex. Proc. Natl. Acad. Sci. USA 105 (2008) 15696–15701. [DOI] [PMID: 18838690]
4.	Cryle, M.J. Selectivity in a barren landscape: the P450(BioI)-ACP complex. Biochem. Soc. Trans. 38 (2010) 934–939. [DOI] [PMID: 20658980]

[EC 1.14.14.46 created 2013 as EC 1.14.15.12, transferred 2017 to EC 1.14.14.46]

1.14.14.47

Accepted name:

nitric-oxide synthase (flavodoxin)

Reaction:

2 L-arginine + 3 reduced flavodoxin + 4 O₂ = 2 L-citrulline + 2 nitric oxide + 3 oxidized flavodoxin + 4 H₂O (overall reaction)
(1a) 2 L-arginine + 2 reduced flavodoxin + 2 O₂ = 2 N^ω-hydroxy-L-arginine + 2 oxidized flavodoxin + 2 H₂O
(1b) 2 N^ω-hydroxy-L-arginine + reduced flavodoxin + 2 O₂ = 2 L-citrulline + 2 nitric oxide + oxidized flavodoxin + 2 H₂O

Glossary:

nitric oxide = NO = nitrogen(II) oxide

Other name(s):

nitric oxide synthetase (ambiguous); NO synthase (ambiguous)

Systematic name:

L-arginine,reduced-flavodoxin:oxygen oxidoreductase (nitric-oxide-forming)

Comments:

Binds heme (iron protoporphyrin IX) and tetrahydrobiopterin. The enzyme, found in bacteria and archaea, consist of only an oxygenase domain and functions together with bacterial ferredoxins or flavodoxins. The orthologous enzymes from plants and animals also contain a reductase domain and use only NADPH as the electron donor (cf. EC 1.14.13.39).

Links to other databases:

References:

1.	Pant, K., Bilwes, A.M., Adak, S., Stuehr, D.J. and Crane, B.R. Structure of a nitric oxide synthase heme protein from Bacillus subtilis. Biochemistry 41 (2002) 11071–11079. [DOI] [PMID: 12220171]
2.	Adak, S., Aulak, K.S. and Stuehr, D.J. Direct evidence for nitric oxide production by a nitric-oxide synthase-like protein from Bacillus subtilis. J. Biol. Chem. 277 (2002) 16167–16171. [DOI] [PMID: 11856757]
3.	Wang, Z.Q., Lawson, R.J., Buddha, M.R., Wei, C.C., Crane, B.R., Munro, A.W. and Stuehr, D.J. Bacterial flavodoxins support nitric oxide production by Bacillus subtilis nitric-oxide synthase. J. Biol. Chem. 282 (2007) 2196–2202. [DOI] [PMID: 17127770]
4.	Agapie, T., Suseno, S., Woodward, J.J., Stoll, S., Britt, R.D. and Marletta, M.A. NO formation by a catalytically self-sufficient bacterial nitric oxide synthase from Sorangium cellulosum. Proc. Natl. Acad. Sci. USA 106 (2009) 16221–16226. [DOI] [PMID: 19805284]
5.	Holden, J.K., Lim, N. and Poulos, T.L. Identification of redox partners and development of a novel chimeric bacterial nitric oxide synthase for structure activity analyses. J. Biol. Chem. 289 (2014) 29437–29445. [DOI] [PMID: 25194416]

[EC 1.14.14.47 created 2012 as EC 1.14.13.165, transferred 2017 to EC 1.14.14.47]

1.14.14.48

Accepted name:

jasmonoyl-L-amino acid 12-hydroxylase

Reaction:

a jasmonoyl-L-amino acid + [reduced NADPH—hemoprotein reductase] + O₂ = a 12-hydroxyjasmonoyl-L-amino acid + [oxidized NADPH—hemoprotein reductase] + H₂O

Glossary:

jasmonic acid = {(1R,2R)-3-oxo-2-[(2Z)pent-2-en-1-yl]cyclopentyl}acetic acid
(+)-7-epi-jasmonic acid = {(1R,2S)-3-oxo-2-[(2Z)pent-2-en-1-yl]cyclopentyl}acetic acid

Other name(s):

CYP94B1 (gene name); CYP94B3 (gene name)

Systematic name:

jasmonoyl-L-amino acid,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (12-hydroxylating)

Comments:

A cytochrome P450 (heme thiolate) enzyme found in plants. The enzyme acts on jasmonoyl-L-amino acid conjugates, catalysing the hydroxylation of the C-12 position of jasmonic acid. While the best studied substrate is (+)-7-epi-jasmonoyl-L-isoleucine, the enzyme was shown to be active with jasmonoyl-L-valine and jasmonoyl-L-phenylalanine, and is likely to be active with other jasmonoyl-amino acid conjugates.

Links to other databases:

References:

1.	Koo, A.J., Cooke, T.F. and Howe, G.A. Cytochrome P450 CYP94B3 mediates catabolism and inactivation of the plant hormone jasmonoyl-L-isoleucine. Proc. Natl. Acad. Sci. USA 108 (2011) 9298–9303. [DOI] [PMID: 21576464]
2.	Kitaoka, N., Matsubara, T., Sato, M., Takahashi, K., Wakuta, S., Kawaide, H., Matsui, H., Nabeta, K. and Matsuura, H. Arabidopsis CYP94B3 encodes jasmonyl-L-isoleucine 12-hydroxylase, a key enzyme in the oxidative catabolism of jasmonate. Plant Cell Physiol. 52 (2011) 1757–1765. [DOI] [PMID: 21849397]
3.	Heitz, T., Widemann, E., Lugan, R., Miesch, L., Ullmann, P., Desaubry, L., Holder, E., Grausem, B., Kandel, S., Miesch, M., Werck-Reichhart, D. and Pinot, F. Cytochromes P450 CYP94C1 and CYP94B3 catalyze two successive oxidation steps of plant hormone jasmonoyl-isoleucine for catabolic turnover. J. Biol. Chem. 287 (2012) 6296–6306. [DOI] [PMID: 22215670]
4.	Kitaoka, N., Kawaide, H., Amano, N., Matsubara, T., Nabeta, K., Takahashi, K. and Matsuura, H. CYP94B3 activity against jasmonic acid amino acid conjugates and the elucidation of 12-O-β-glucopyranosyl-jasmonoyl-L-isoleucine as an additional metabolite. Phytochemistry 99 (2014) 6–13. [DOI] [PMID: 24467969]
5.	Koo, A.J., Thireault, C., Zemelis, S., Poudel, A.N., Zhang, T., Kitaoka, N., Brandizzi, F., Matsuura, H. and Howe, G.A. Endoplasmic reticulum-associated inactivation of the hormone jasmonoyl-L-isoleucine by multiple members of the cytochrome P450 94 family in Arabidopsis. J. Biol. Chem. 289 (2014) 29728–29738. [DOI] [PMID: 25210037]
6.	Widemann, E., Grausem, B., Renault, H., Pineau, E., Heinrich, C., Lugan, R., Ullmann, P., Miesch, L., Aubert, Y., Miesch, M., Heitz, T. and Pinot, F. Sequential oxidation of jasmonoyl-phenylalanine and jasmonoyl-isoleucine by multiple cytochrome P450 of the CYP94 family through newly identified aldehyde intermediates. Phytochemistry 117 (2015) 388–399. [DOI] [PMID: 26164240]

[EC 1.14.14.48 created 2017]

1.14.14.49

Accepted name:

12-hydroxyjasmonoyl-L-amino acid 12-hydroxylase

Reaction:

a 12-hydroxyjasmonoyl-L-amino acid + 2 [reduced NADPH—hemoprotein reductase] + 2 O₂ = a 12-hydroxy-12-oxojasmonoyl-L-amino acid + 2 [oxidized NADPH—hemoprotein reductase] + 3 H₂O (overall reaction)
(1a) a 12-hydroxyjasmonoyl-L-amino acid + [reduced NADPH—hemoprotein reductase] + O₂ = a 12-oxojasmonoyl-L-amino acid + [oxidized NADPH—hemoprotein reductase] + 2 H₂O
(1b) a 12-oxojasmonoyl-L-amino acid + [reduced NADPH—hemoprotein reductase] + O₂ = a 12-hydroxy-12-oxojasmonoyl-L-amino acid + [oxidized NADPH—hemoprotein reductase] + H₂O

Glossary:

12-hydroxy-12-oxojasmonate = (3Z)-5-[(1R,2R)-2-(carboxymethyl)-5-oxocyclopentyl]pent-3-enoate

Other name(s):

CYP94C1 (gene name)

Systematic name:

12-hydroxyjasmonoyl-L-amino acid,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (12-hydroxylating)

Comments:

A cytochrome P450 (heme thiolate) enzyme found in plants. The enzyme acts on jasmonoyl-L-amino acid conjugates that have been hydroxylated at the C-12 position of jasmonic acid by EC 1.14.14.48, jasmonoyl-L-amino acid 12-hydroxylase, further oxidizing that position to a carboxylate via an aldehyde intermediate. While the best studied substrate is (+)-7-epi-jasmonoyl-L-isoleucine, the enzyme was shown to be active with jasmonoyl-L-phenylalanine, and is likely to be active with other jasmonoyl-amino acid conjugates.

Links to other databases:

References:

1.	Heitz, T., Widemann, E., Lugan, R., Miesch, L., Ullmann, P., Desaubry, L., Holder, E., Grausem, B., Kandel, S., Miesch, M., Werck-Reichhart, D. and Pinot, F. Cytochromes P450 CYP94C1 and CYP94B3 catalyze two successive oxidation steps of plant hormone jasmonoyl-isoleucine for catabolic turnover. J. Biol. Chem. 287 (2012) 6296–6306. [DOI] [PMID: 22215670]
2.	Widemann, E., Grausem, B., Renault, H., Pineau, E., Heinrich, C., Lugan, R., Ullmann, P., Miesch, L., Aubert, Y., Miesch, M., Heitz, T. and Pinot, F. Sequential oxidation of jasmonoyl-phenylalanine and jasmonoyl-isoleucine by multiple cytochrome P450 of the CYP94 family through newly identified aldehyde intermediates. Phytochemistry 117 (2015) 388–399. [DOI] [PMID: 26164240]
3.	Bruckhoff, V., Haroth, S., Feussner, K., Konig, S., Brodhun, F. and Feussner, I. Functional characterization of CYP94-genes and identification of a novel jasmonate catabolite in flowers. PLoS One 11 (2016) e0159875. [DOI] [PMID: 27459369]

[EC 1.14.14.49 created 2017]

1.14.14.50

Accepted name:

tabersonine 3-oxygenase

Reaction:

(1) 16-methoxytabersonine + [reduced NADPH—hemoprotein reductase] + O₂ = (3R)-3-hydroxy-16-methoxy-1,2-didehydro-2,3-dihydrotabersonine + [oxidized NADPH—hemoprotein reductase] + H₂O
(2) tabersonine + [reduced NADPH—hemoprotein reductase] + O₂ = (3R)-3-hydroxy-1,2-didehydro-2,3-dihydrotabersonine + [oxidized NADPH—hemoprotein reductase] + H₂O

For diagram of vindoline biosynthesis, click here

Other name(s):

T3O; CYP71D1V2

Systematic name:

16-methoxytabersonine,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (3-hydroxylating)

Comments:

This cytochrome P-450 (heme thiolate) enzyme acts on 16-methoxytabersonine, leading to biosynthesis of vindoline in the plant Catharanthus roseus (Madagascar periwinkle). It can also act on tabersonine, resulting in the production of small amounts of vindorosine. The products are unstable and, in the absence of EC 1.1.99.41, 3-hydroxy-1,2-didehydro-2,3-dihydrotabersonine reductase, will convert into 3-epoxylated compounds.

Links to other databases: