The ginsenoside Rgfound in Panax species has extensive pharmacological properties,in particular anti-cancer effects.However,its natural yield in Panax plants is limited.Here,we report a multimodular strategy to improv...The ginsenoside Rgfound in Panax species has extensive pharmacological properties,in particular anti-cancer effects.However,its natural yield in Panax plants is limited.Here,we report a multimodular strategy to improve yields of Rgin a Panax ginseng chassis,combining engineering of triterpene metabolism and overexpression of a lignin biosynthesis gene,phenylalanine ammonia lyase(PAL).We first performed semi-rational design and site mutagenesis to improve the enzymatic efficiency of Pq3-O-UGT2,a glycosyltransferase that directly catalyzes the biosynthesis of Rgfrom Rh.Next,we used clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)gene editing to knock down the branch pathway of protopanaxatriol-type ginsenoside biosynthesis to enhance the metabolic flux of the protopanaxadiol-type ginsenoside Rg.Overexpression of PAL accelerated the formation of the xylem structure,significantly improving ginsenoside Rgaccumulation(to 6.19-fold higher than in thecontrol).Wecombinedoverexpression of the ginsenoside aglycon synthetic genes squalene epoxidase,Pq3-O-UGT2,and PAL with CRISPR/Cas9-based knockdown of CYP716A53v2 to improve ginsenoside Rgaccumulation.Finally,we produced ginsenoside Rgat a yield of 83.6 mg/L in a shake flask(7.0 mg/g dry weight,21.12-fold higher than with wild-type cultures).The highproduction system established in this study could be a potential platform to produce the ginsenoside Rgcommercially for pharmaceutical use.展开更多
基金financial support from the National Key Research and Development Program(2020YFA0907903)a key project at the central government level:“The ability to establish a sustainable use for valuable Chinese medicine resources”(2060302)+2 种基金the National Science Foundation of China(91954112 and 31900501)the Young Elite Scientists Sponsorship Program of Tianjin(TJSQNTJ-2020-19)the Scientific Research Transformation Foundation of the Wenzhou Safety(Emergency)Institute of Tianjin University。
文摘The ginsenoside Rgfound in Panax species has extensive pharmacological properties,in particular anti-cancer effects.However,its natural yield in Panax plants is limited.Here,we report a multimodular strategy to improve yields of Rgin a Panax ginseng chassis,combining engineering of triterpene metabolism and overexpression of a lignin biosynthesis gene,phenylalanine ammonia lyase(PAL).We first performed semi-rational design and site mutagenesis to improve the enzymatic efficiency of Pq3-O-UGT2,a glycosyltransferase that directly catalyzes the biosynthesis of Rgfrom Rh.Next,we used clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)gene editing to knock down the branch pathway of protopanaxatriol-type ginsenoside biosynthesis to enhance the metabolic flux of the protopanaxadiol-type ginsenoside Rg.Overexpression of PAL accelerated the formation of the xylem structure,significantly improving ginsenoside Rgaccumulation(to 6.19-fold higher than in thecontrol).Wecombinedoverexpression of the ginsenoside aglycon synthetic genes squalene epoxidase,Pq3-O-UGT2,and PAL with CRISPR/Cas9-based knockdown of CYP716A53v2 to improve ginsenoside Rgaccumulation.Finally,we produced ginsenoside Rgat a yield of 83.6 mg/L in a shake flask(7.0 mg/g dry weight,21.12-fold higher than with wild-type cultures).The highproduction system established in this study could be a potential platform to produce the ginsenoside Rgcommercially for pharmaceutical use.
