Abstract
We have characterized four sequential enzymes that transform 1-hydroxy-N-methylcanadine to narcotoline hemiacetal, completing our elucidation of noscapine biosynthesis in opium poppy. Two cytochromes P450 catalyze hydroxylations at C13 and C8 on the protoberberine scaffold, the latter step inducing ring opening and the formation of an aldehyde moiety. Acetylation at C13 before C8 hydroxylation introduces a protective group subsequently hydrolyzed by a carboxylesterase, which triggers rearrangement to a cyclic hemiacetal.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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Acetylation
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Berberine / analogs & derivatives
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Berberine / chemistry
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Berberine / metabolism
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Biosynthetic Pathways
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Cyclization
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Gene Expression Regulation, Enzymologic
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Gene Expression Regulation, Plant
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Gene Silencing
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Hydroxylation
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Noscapine / chemistry
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Noscapine / metabolism*
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Papaver / enzymology*
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Papaver / genetics
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Plant Proteins / chemistry
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Plant Proteins / genetics
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Plant Proteins / metabolism*
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Recombinant Proteins / chemistry
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Recombinant Proteins / genetics
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Recombinant Proteins / metabolism
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Substrate Specificity
Substances
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Plant Proteins
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Recombinant Proteins
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Berberine
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Noscapine
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canadine
Associated data
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PubChem-Substance/223367241
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PubChem-Substance/223367242