Cargando…

Characterization of the Asiatic Acid Glucosyltransferase, UGT73AH1, Involved in Asiaticoside Biosynthesis in Centella asiatica (L.) Urban

Centella asiatica (L.) Urban contains two ursane-type triterpene saponins, asiaticoside and madecassoside, as major secondary metabolites. In order to select candidate genes encoding UDP-glucosyltransferases (UGTs) involved in asiaticoside biosynthesis, we performed transcriptomic analysis of leaves...

Descripción completa

Detalles Bibliográficos
Autores principales: Kim, Ok Tae, Jin, Mei Lan, Lee, Dae Young, Jetter, Reinhard
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5751233/
https://www.ncbi.nlm.nih.gov/pubmed/29210992
http://dx.doi.org/10.3390/ijms18122630
_version_ 1783289903879028736
author Kim, Ok Tae
Jin, Mei Lan
Lee, Dae Young
Jetter, Reinhard
author_facet Kim, Ok Tae
Jin, Mei Lan
Lee, Dae Young
Jetter, Reinhard
author_sort Kim, Ok Tae
collection PubMed
description Centella asiatica (L.) Urban contains two ursane-type triterpene saponins, asiaticoside and madecassoside, as major secondary metabolites. In order to select candidate genes encoding UDP-glucosyltransferases (UGTs) involved in asiaticoside biosynthesis, we performed transcriptomic analysis of leaves elicited by methyl jasmonate (MeJA). Among the unigenes, 120 isotigs and 13 singletons of unique sequences were annotated as UGTs, including 37 putative full-length cDNAs, and 15 of the putative UGT genes were named according to the UGT committee nomenclature protocols. One of them, UGT73AH1, was characterized by heterologous expression in Escherichia coli BL21 (DE3) cells. After induction with IPTG, a total protein extract was assayed with UDP-glucose and asiatic acid. UPLC-QTOF/MS analysis showed that UGT73AH1 catalyzes the glycosylation of asiatic acid to its monoglucoside. It remains unclear whether glycosylation occurs on the triterpene C-2α, C-3β, C-23, or C-28 position. However, it is very likely that UGT73AH1 glucosylates the C-28 position, because only C-28 bears a glucose moiety in the final pathway product of asiatic acid, while C-2α, C-3β, and C-23 remain un-conjugated.
format Online
Article
Text
id pubmed-5751233
institution National Center for Biotechnology Information
language English
publishDate 2017
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-57512332018-01-08 Characterization of the Asiatic Acid Glucosyltransferase, UGT73AH1, Involved in Asiaticoside Biosynthesis in Centella asiatica (L.) Urban Kim, Ok Tae Jin, Mei Lan Lee, Dae Young Jetter, Reinhard Int J Mol Sci Article Centella asiatica (L.) Urban contains two ursane-type triterpene saponins, asiaticoside and madecassoside, as major secondary metabolites. In order to select candidate genes encoding UDP-glucosyltransferases (UGTs) involved in asiaticoside biosynthesis, we performed transcriptomic analysis of leaves elicited by methyl jasmonate (MeJA). Among the unigenes, 120 isotigs and 13 singletons of unique sequences were annotated as UGTs, including 37 putative full-length cDNAs, and 15 of the putative UGT genes were named according to the UGT committee nomenclature protocols. One of them, UGT73AH1, was characterized by heterologous expression in Escherichia coli BL21 (DE3) cells. After induction with IPTG, a total protein extract was assayed with UDP-glucose and asiatic acid. UPLC-QTOF/MS analysis showed that UGT73AH1 catalyzes the glycosylation of asiatic acid to its monoglucoside. It remains unclear whether glycosylation occurs on the triterpene C-2α, C-3β, C-23, or C-28 position. However, it is very likely that UGT73AH1 glucosylates the C-28 position, because only C-28 bears a glucose moiety in the final pathway product of asiatic acid, while C-2α, C-3β, and C-23 remain un-conjugated. MDPI 2017-12-06 /pmc/articles/PMC5751233/ /pubmed/29210992 http://dx.doi.org/10.3390/ijms18122630 Text en © 2017 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Kim, Ok Tae
Jin, Mei Lan
Lee, Dae Young
Jetter, Reinhard
Characterization of the Asiatic Acid Glucosyltransferase, UGT73AH1, Involved in Asiaticoside Biosynthesis in Centella asiatica (L.) Urban
title Characterization of the Asiatic Acid Glucosyltransferase, UGT73AH1, Involved in Asiaticoside Biosynthesis in Centella asiatica (L.) Urban
title_full Characterization of the Asiatic Acid Glucosyltransferase, UGT73AH1, Involved in Asiaticoside Biosynthesis in Centella asiatica (L.) Urban
title_fullStr Characterization of the Asiatic Acid Glucosyltransferase, UGT73AH1, Involved in Asiaticoside Biosynthesis in Centella asiatica (L.) Urban
title_full_unstemmed Characterization of the Asiatic Acid Glucosyltransferase, UGT73AH1, Involved in Asiaticoside Biosynthesis in Centella asiatica (L.) Urban
title_short Characterization of the Asiatic Acid Glucosyltransferase, UGT73AH1, Involved in Asiaticoside Biosynthesis in Centella asiatica (L.) Urban
title_sort characterization of the asiatic acid glucosyltransferase, ugt73ah1, involved in asiaticoside biosynthesis in centella asiatica (l.) urban
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5751233/
https://www.ncbi.nlm.nih.gov/pubmed/29210992
http://dx.doi.org/10.3390/ijms18122630
work_keys_str_mv AT kimoktae characterizationoftheasiaticacidglucosyltransferaseugt73ah1involvedinasiaticosidebiosynthesisincentellaasiaticalurban
AT jinmeilan characterizationoftheasiaticacidglucosyltransferaseugt73ah1involvedinasiaticosidebiosynthesisincentellaasiaticalurban
AT leedaeyoung characterizationoftheasiaticacidglucosyltransferaseugt73ah1involvedinasiaticosidebiosynthesisincentellaasiaticalurban
AT jetterreinhard characterizationoftheasiaticacidglucosyltransferaseugt73ah1involvedinasiaticosidebiosynthesisincentellaasiaticalurban