Accepted name: marmesin synthase
Reaction: demethylsuberosin + [reduced NADPH—hemoprotein reductase] + O2 = (+)-marmesin + [oxidized NADPH—hemoprotein reductase] + H2O
Glossary: demethylsuberosin = 7-hydroxy-6-prenyl-1-benzopyran-2-one
(+)-marmesin = (S)-2-(2-hydroxypropan-2-yl)-2,3-dihydro-7H-furo[3,2-g]chromen-7-one
Systematic name: demethylsuberosin,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase
Comments: A P-450 monoxygenase involved in psoralen biosynthesis, see EC, psoralen synthase.
1.  Hamerski, D. and Matern, U. Elicitor-induced biosynthesis of psoralens in Ammi majus L. suspension cultures. Microsomal conversion of demethylsuberosin into (+)marmesin and psoralen. Eur. J. Biochem. 171 (1988) 369–375. [PMID: 2828055]
[EC created 2018]
Accepted name: umbelliferone 6-dimethylallyltransferase
Reaction: prenyl diphosphate + umbelliferone = diphosphate + demethylsuberosin
Glossary: demethylsuberosin = 7-hydroxy-6-prenyl-1-benzopyran-2-one
osthenol = 7-hydroxy-8-prenyl-1-benzopyran-2-one
Other name(s): PcPT; dimethylallyl-diphosphate:umbelliferone 6-dimethylallyltransferase
Systematic name: prenyl-diphosphate:umbelliferone 6-prenyltransferase
Comments: The enzyme from parsley (Petroselinum crispum) is specific for umbelliferone and prenyl diphosphate. A minor product is osthenol, which is produced by transfer of the prenyl group to C-8 of umbelliferone.
1.  Hamerski, D., Schmitt, D. and Matern, U. Induction of two prenyltransferases for the accumulation of coumarin phytoalexins in elicitor-treated Ammi majus cell suspension cultures. Phytochemistry 29 (1990) 1131–1135. [PMID: 1366425]
2.  Karamat, F., Olry, A., Munakata, R., Koeduka, T., Sugiyama, A., Paris, C., Hehn, A., Bourgaud, F. and Yazaki, K. A coumarin-specific prenyltransferase catalyzes the crucial biosynthetic reaction for furanocoumarin formation in parsley. Plant J. 77 (2014) 627–638. [PMID: 24354545]
[EC created 2017]