EC 1.14.14.145     
Accepted name: abieta-7,13-dien-18-ol hydroxylase
Reaction: abieta-7,13-dien-18-ol + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = abieta-7,13-dien-18-oate + 2 [oxidized NADPH—hemoprotein reductase] + 3 H2O (overall reaction)
(1a) abieta-7,13-dien-18-ol + [reduced NADPH—hemoprotein reductase] + O2 = abieta-7,13-dien-18,18-diol + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) abieta-7,13-dien-18,18-diol = abieta-7,13-dien-18-al + H2O (spontaneous)
(1c) abieta-7,13-dien-18-al + [reduced NADPH—hemoprotein reductase] + O2 = abieta-7,13-dien-18-oate + [oxidized NADPH—hemoprotein reductase] + H2O
Glossary: abieta-7,13-dien-18-ol = ((1R,4aR,4bR,10aR)-7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-decahydrophenanthren-1-yl)methanol
abieta-7,13-dien-18-al = (1R,4aR,4bR,10aR)-7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-decahydrophenanthrene-1-carbaldehyde
Other name(s): CYP720B1; PtAO; abietadienol hydroxylase (ambiguous)
Systematic name: abieta-7,13-dien-18-ol,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (18-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein. This enzyme catalyses a step in the pathway of abietic acid biosynthesis. The activity has been demonstrated in cell-free stem extracts of Abies grandis (grand fir) and Pinus contorta (lodgepole pine) [1], and the gene encoding the enzyme has been identified in Pinus taeda (loblolly pine) [3]. The recombinant enzyme catalyses the oxidation of multiple diterpene alcohol and aldehydes, including levopimaradienol, isopimara-7,15-dienol, isopimara-7,15-dienal, dehydroabietadienol and dehydroabietadienal. It is not able to oxidize abietadiene.
References:
1.  Funk, C. and Croteau, R. Diterpenoid resin acid biosynthesis in conifers: characterization of two cytochrome P450-dependent monooxygenases and an aldehyde dehydrogenase involved in abietic acid biosynthesis. Arch. Biochem. Biophys. 308 (1994) 258–266. [PMID: 8311462]
2.  Funk, C., Lewinsohn, E., Vogel, B.S., Steele, C.L. and Croteau, R. Regulation of oleoresinosis in grand fir (Abies grandis) (coordinate induction of monoterpene and diterpene cyclases and two cytochrome P450-dependent diterpenoid hydroxylases by stem wounding). Plant Physiol. 106 (1994) 999–1005. [PMID: 12232380]
3.  Ro, D.K., Arimura, G., Lau, S.Y., Piers, E. and Bohlmann, J. Loblolly pine abietadienol/abietadienal oxidase PtAO (CYP720B1) is a multifunctional, multisubstrate cytochrome P450 monooxygenase. Proc. Natl. Acad. Sci. USA 102 (2005) 8060–8065. [PMID: 15911762]
[EC 1.14.14.145 created 2009 as EC 1.14.13.109, modified 2012, transferred 2018 to EC 1.14.14.145]