Horticulture, Environment, and Biotechnology

, Volume 58, Issue 6, pp 613–619 | Cite as

Functional characterization of the β-amyrin synthase gene involved in platycoside biosynthesis in Platycodon grandiflorum

  • Yurry Um
  • Mei Lan Jin
  • Dae Young Lee
  • Chang Kug Kim
  • Chang Pyo Hong
  • Yi Lee
  • Ok Tae Kim
Research Report


Platycodon grandiflorum A. DC. contains a variety of triterpene saponins induced from the base structure of oleanane-type in roots. The β-amyrin synthase (bAS) plays an important role in controlling the biosynthesis of triterpene saponins and we obtained the full-length cDNA of the gene, which is named PlgOSC1 in P. grandiflorum. To identify the PlgOSC1 products, we expressed it in heterologous yeast cells. Results of GC-MS analysis showed a unique peak that was consistent with that of the authentic β-amyrin standard with exactly the same retention time. Furthermore, the pattern of MS fragments of the peak was also exactly the same as that of the β-amyrin. In qRT-PCR analysis of four organs of P. grandiflorum, no difference in PlgOSC1 expression level was observed; therefore, platycosides derived from β-amyrin might be present in all P. grandiflorum tissues. In conclusion, PlgOSC1 encodes a bAS enzyme that catalyzes the first committed step of platycosides biosynthesis in P. grandiflorum.

Additional key words

beta-amyrin synthase oxidosqualene cyclase platycosides triterpenoids 


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Supplementary material

13580_2017_54_MOESM1_ESM.xlsx (14 kb)
Supplementary Table 1. Accession data for the OSCs used in the phylogenetic analyses.


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Copyright information

© Korean Society for Horticultural Science and Springer-Verlag GmbH Germany, part of Springer Nature 2017

Authors and Affiliations

  • Yurry Um
    • 1
  • Mei Lan Jin
    • 1
  • Dae Young Lee
    • 1
  • Chang Kug Kim
    • 2
  • Chang Pyo Hong
    • 3
  • Yi Lee
    • 4
  • Ok Tae Kim
    • 1
  1. 1.Department of Herbal Crop ResearchNational Institute of Horticultural and Herbal Science, RDAEumseongRepublic of Korea
  2. 2.Genomics DivisionNational Academy of Agricultural Science (NAAS), RDAJeonjuRepublic of Korea
  3. 3.Theragen Etex Bio Institute, Theragen EtexSuwonRepublic of Korea
  4. 4.Department of Industrial Plant Science and TechnologyChungbuk National UniversityCheongjuRepublic of Korea

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