Cytochrome P450 CYP716A53v2 Catalyzes the Formation of Protopanaxatriol from Protopanaxadiol During Ginsenoside Biosynthesis in Panax Ginseng
Open Access
- 7 August 2012
- journal article
- research article
- Published by Oxford University Press (OUP) in Plant and Cell Physiology
- Vol. 53 (9), 1535-1545
- https://doi.org/10.1093/pcp/pcs106
Abstract
Ginseng (Panax ginseng C.A. Meyer) is one of the most popular medicinal herbs, and the root of this plant contains pharmacologically active components, called ginsenosides. Ginsenosides, a class of tetracyclic triterpene saponins, are synthesized from dammarenediol-II after hydroxylation by cytochrome P450 (CYP) and then glycosylation by a glycosyltransferase. Protopanaxadiol synthase, which is a CYP enzyme (CYP716A47) that catalyzes the hydroxylation of dammarenediol-II at the C-12 position to yield protopanaxadiol, was recently characterized. Here, we isolated two additional CYP716A subfamily genes (CYP716A52v2 and CYP716A53v2) and determined that the gene product of CYP716A53v2 is a protopanaxadiol 6-hydroxylase that catalyzes the formation of protopanaxatriol from protopanaxadiol during ginsenoside biosynthesis in P. ginseng. Both CYP716A47 and CYP716A53v2 mRNAs accumulated ubiquitously in all organs of ginseng plants. In contrast, CYP716A52v2 mRNA accumulated only in the rhizome. Methyl jasmonate (MeJA) treatment resulted in the obvious accumulation of CYP716A47 mRNA in adventitious roots. However, neither CYP716A52v2 nor CYP716A53v2 mRNA was affected by MeJA treatment during the entire culture period. The ectopic expression of CYP716A53v2 in recombinant WAT21 yeast resulted in protopanaxatriol production after protopanaxadiol was added to the culture medium. In vitro enzymatic activity assays revealed that CYP716A53v2 catalyzed the oxidation of protopanaxadiol to produce protopanaxatriol. The chemical structures of the protopanaxatriol products were confirmed using liquid chromatography–atmospheric pressure chemical ionization mass spectrometry (LC/APCIMS). Our results indicate that the gene product of CYP716A53v2 is a protopanaxadiol 6-hydroxylase that produces protopanaxatriol from protopanaxadiol, which is an important step in the formation of dammarane-type triterpene aglycones in ginseng saponin biosynthesis.Keywords
This publication has 37 references indexed in Scilit:
- Triterpene Functional Genomics in Licorice for Identification of CYP72A154 Involved in the Biosynthesis of GlycyrrhizinTHE PLANT CELL ONLINE, 2011
- The Cyt P450 Enzyme CYP716A47 Catalyzes the Formation of Protopanaxadiol from Dammarenediol-II During Ginsenoside Biosynthesis in Panax ginsengPlant and Cell Physiology, 2011
- CYP716A Subfamily Members are Multifunctional Oxidases in Triterpenoid BiosynthesisPlant and Cell Physiology, 2011
- Medicago truncatula CYP716A12 Is a Multifunctional Oxidase Involved in the Biosynthesis of Hemolytic SaponinsTHE PLANT CELL ONLINE, 2011
- Identification and characterisation of CYP75A31, a new flavonoid 3'5'-hydroxylase, isolated from Solanum lycopersicumBMC Plant Biology, 2010
- Licorice β-amyrin 11-oxidase, a cytochrome P450 with a key role in the biosynthesis of the triterpene sweetener glycyrrhizinProceedings of the National Academy of Sciences of the United States of America, 2008
- Plant Cytochrome P450 MonooxygenasesCritical Reviews in Plant Sciences, 1996
- CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choiceNucleic Acids Research, 1994
- Improved method for high efficiency transformation of intact yeast cellsNucleic Acids Research, 1992
- Confidence Limits on Phylogenies: An Approach Using the BootstrapEvolution, 1985