Norcoclaurine 6-O-methyltransferase

The three cDNAs of norcoclaurine-6-O-methyltransferase, coclaurine-AA methyltransferase and 3 -hydroxy-AAmethylcoclaurine 4,-<9-methyltransferase converting (R, S)-norlaudanosoline into (R, Sj-reticuline with a 5-10% yield... 

Ounaroon, A., G. Decker, J. Schmidt, F. Lottspeich and T.M. Kutchan, (R,S)-Reticuline 7-O-methyltransferase and (R,S)-Norcoclaurine 6-O-Methyltransferase of Papaver... 

Ounaroon A, Decker G, Schmidt J, Lottspeich F, Kutchan TM. (R,S)-reticuline 7-0-methyltransferase and (R,S)- norcoclaurine 6-O-methyltransferase of Papaver somniferum - cDNA cloning and characterization of methyl transfer enzymes of alkaloid biosynthesis in opium poppy. Plant J. 2003 36 808-819. 

Sato F, Tsujita T, Katagiri Y, Yoshida S, Yamada Y. Purification and characterization of S-adenosyl-L-methionine norcoclaurine 6-O-methyltransferase from cultured Coptis japonica cells. Eur. J. Biochem. 1994 225 125-131. 

Fig. 4 Pathways of benzylisoquinoline biosynthesis. A selection of biosynthetic enzymes is notified with their localization in the cytosol (yellow), the ER membrane (red) or in the lumen of cytosolic vesicles (blue). Informations are taken mainly from Facchini and St-Pierre (2005), Bock et al. (2002), own experiments and other references cited in the text. BBE, berberine bridge enzyme CFS, cheilanthifoline synthase CNMT, coclaurine N-methyltransferase COR, codeinone reductase DBOX, dihydrobenzophen-anthridine oxidase MSH, N-methylstylopine 14-hydroxylase NCS, norcoclaurine synthase NMCH, N-methylcoclaurme 3 -hydroxylase 4 OMT, 3 -hydroxy-N-methylcoclaurine 4 -0-methyltransferase 60MT, norcoclaurine 6-O-methyltransferase 70MT, reticuline 7-O-methyltransferase P6H, protopine 6-hydroxylase SAT, salutaridinol-7-O-acetyltransferase SOR, salutaridineiNADPH 7-oxidoreductase STS, stylopine synthase SAS, salutaridine synthase TNMT, tetrahydroprotoberberine cis-N-methyltrans-ferase TYDC, tyrosine decarboxylase CAS, canadine sjmthase SOMT, scoulerine 9-O-methyltransferase STOX, (S)-tetrahydroprotoberberine oxidase...

Figure 4.2 Biosynthesis of benzylisoquinoline alkaloids. Enzyme abbreviations TYDC, tyrosine/dopa decarboxylase NCS, norcoclaurine synth lse 60MT, norcoclaurine 6-O-methyltransferase 4 OMT, 3 -hydroxy-/V-methylcoclaurine 4 -0-methyltransferase CYP80A, berbamunine synth lse CYP80B, N-methylcoclaurine 3 -hydroxylase BBE, berberine bridge enzyme SOMT, scoulerine 9-0-methyltransferase CYP719A, (S)-canadine synthase SAT, salutaridinol 7-O-acetyltransferase COR, codeinone reductase.

Fig. 10.8 Selected cDNAs isolated in recent years that encode enzymes involved in the biosynthesis of various classes of isoquinoline alkaloids. 6-OMT, norcoclaurine 6-0-methyltransferase 23 CYP80A1, berbamunine synthase 19 CYP80B1, (S)-A-methylcoclaurine 3 -hydroxylase 20 CPR, cytochrome P-450 reductase 29 4 -OMT, (5)-3 -hydroxy-A-methylcoclaurine 4 -0-methyltransferase 30 BBE, berberine bridge enzyme 12 SalAT, salutaridinol 7-O-acetyltransferase 28 COR, codeinone reductase.25...

Figure 2.5 Formation of (5)-reticuline. NCS, norcoclaurine synthase 60MT, 6-hydroxy-O-methyltransferase CNMT, coclaurine N-methyltransferase 40MT, 4 hydroxy-0-methyltransferase.

Fig. 8.6 Biosynthetic pathway for benzylisoquinoline alkaloid (BIA) biosynthesis in plants. TYDC tyrosine/dopa decarhoxylase, 60MT norcoclaurine b-O-methyltransfoase, 40OMT 30-hydroxy-Af-methylcoclaurine 40-O-methyltransferase, OMT ITl O-methyltransferase II-l, CYP80A1 berbamunine synthase, CYP80B1 (Si-N-methylcoclaurine 30-hydroxylase, btaber-ine bridge enzyme, SOMT scoulerine iV-methyltransferase, COR codeinone rednctase (Adopted from Ref. [3])...

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