Editing Scopolamine (section)

==Chemistry==

=== Biosynthesis in plants ===
Scopolamine is among the [[secondary metabolites]] of plants from the [[Solanaceae]] (nightshade) family of plants, including [[henbane]] (''Hyoscyamus niger''), [[jimson weed]] (''[[Datura]]''), angel's trumpets (''[[Brugmansia]]''), deadly nightshade (''[[Atropa belladonna|Belladonna]]''), mandrake (''[[Mandragora officinarum]]''), and corkwood (''[[Duboisia]]'').<ref name = "Muranaka_1993">{{cite journal | vauthors = Muranaka T, Ohkawa H, Yamada Y |title = Continuous Production of Scopolamine by a Culture of ''Duboisia leichhardtii'' Hairy Root Clone in a Bioreactor System |journal = Applied Microbiology and Biotechnology |volume = 40 |issue = 2–3 |pages = 219–223 |year = 1993 |doi = 10.1007/BF00170370 |s2cid = 45125074 }}</ref><ref name=Chambers/>

[[File:Tropane alkaloids biochemistry.png|class=skin-invert-image|thumb|The biochemistry of tropane class compounds]]
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The [[biosynthesis]] of scopolamine begins with the [[decarboxylation]] of [[L-ornithine]] to [[putrescine]] by [[ornithine decarboxylase]]. Putrescine is [[Methylation|methylated]] to N-methylputrescine by [[putrescine N-methyltransferase]].<ref name="Ziegler2008">{{cite journal | vauthors = Ziegler J, Facchini PJ | title = Alkaloid biosynthesis: metabolism and trafficking | journal = Annual Review of Plant Biology | volume = 59 | issue = 1 | pages = 735–769 | year = 2008 | pmid = 18251710 | doi = 10.1146/annurev.arplant.59.032607.092730 | bibcode = 2008AnRPB..59..735Z }}</ref>

A [[putrescine oxidase]] that specifically recognizes methylated putrescine catalyzes the [[deamination]] of this compound to 4-methylaminobutanal, which then undergoes a spontaneous ring formation to N-[[methyl]]-[[pyrrole|pyrrolium]] cation. In the next step, the pyrrolium cation condenses with [[acetoacetic acid]] yielding [[hygrine]]. No [[enzymatic]] activity could be demonstrated to catalyze this reaction. Hygrine further rearranges to [[tropinone]].<ref name="Ziegler2008" />

Subsequently, [[tropinone reductase I]] converts [[tropinone]] to [[tropine]], which condenses with [[phenylalanine]]-derived phenyllactate to [[littorine]]. A [[cytochrome P450]] classified as Cyp80F1<ref>{{cite journal | vauthors = Li R, Reed DW, Liu E, Nowak J, Pelcher LE, Page JE, Covello PS | title = Functional genomic analysis of alkaloid biosynthesis in Hyoscyamus niger reveals a cytochrome P450 involved in littorine rearrangement | journal = Chemistry & Biology | volume = 13 | issue = 5 | pages = 513–520 | date = May 2006 | pmid = 16720272 | doi = 10.1016/j.chembiol.2006.03.005 | doi-access = free }}</ref> oxidizes and rearranges littorine to hyoscyamine [[aldehyde]]. In the final step, [[hyoscyamine]] undergoes [[epoxidation]] catalyzed by [[6beta-hydroxyhyoscyamine epoxidase|6β-hydroxyhyoscyamine epoxidase]] yielding scopolamine.<ref name="Ziegler2008" />
[[File:Scopolamine biosynthesis.svg|class=skin-invert-image|center|800px]]