Production of bioactive ginsenoside compound K in metabolically engineered yeast

Biosynthesis and biotechnological production of ginsenosides

“…Furthermore, the importance of DDS in synthesizing ginsenosides was shown by experiments using hairy root of transgenic plant suppressing other branch CAS; these roots showed increased DDS enzyme activity and contained 50-100% higher ginsenoside levels compared with control roots (Liang et al, 2009). Hetero-overexpression of DDS successfully produced dammarenediol-II in tobacco cells (Han et al, 2014;Lee et al, 2012) providing a new way to produce ginsenosides with other downstream genes in yeast cell system (Dai et al, 2014;Jung et al, 2014;Yan et al, 2014). DDS is conserved across the Panax species (Niu et al, 2014), and it contains 769 amino acids with six QW-motifs and the substrate binding DCTAE motif.…”

“…In ginseng plants, UGTs are assumed to play an important role in producing different ginsenosides by adding monosaccharides to triterpene aglycones mainly at C-3 and/or C-20 for PPD-type ginsenosides and at C-6 and/or C-20 for PPT-type ginsenosides. Even though several UGT enzymes have been identified in glycosylating triterpene aglycones (Jung et al, 2014;Khorolragchaa et al, 2014;Luo et al, 2011;Xiang et al, 2012;Yan et al, 2014;Yue and Zhong, 2005), the biochemical functions of UGTs in ginseng plants remain largely unknown. Two UGTs, UGRdGT from P. notoginseng and UGRh2GT from P. ginseng, were purified, and were shown to be responsible for the synthesis of ginsenoside Rb1 from Rd, and Rg3 from Rh2, respectively (He and Yue, 2010;Yue and Zhong, 2005).…”

“…Two UGTs, UGRdGT from P. notoginseng and UGRh2GT from P. ginseng, were purified, and were shown to be responsible for the synthesis of ginsenoside Rb1 from Rd, and Rg3 from Rh2, respectively (He and Yue, 2010;Yue and Zhong, 2005). Recently Yan et al (2014) identified UGTPg1 in glycosylating several intermediates, including dammarenediol, PPD, Rh2, and Rg3 at C-20 positions for the production of new compound 20S-O-β-(D-glucosyl)-dammarenediol II (DMG), compound K, a kind of ginsenoside not detectable in ginseng plants, but in human blood, F2, and Rd, respectively, providing insight into ginsenoside biosynthesis.…”

“…Although dried P. ginseng roots contain about 4% ginsenosides, the main functional form observed in mammalian blood after oral consumption of ginseng or ginsenosides is compound K, which was shown to have bioactivities such as anti-inflammation, hepatoprotection, antidiabetes and anti-cancer (Yan et al, 2014). More recently, China Food and Drug Administration approved compound K for clinical trials to prevent and treat arthritis.…”

“…Major ginsenosides of each of the four types are indicated in green: protopanaxadiol (PPD)-type, protopanaxatriol (PPT)-type, oleanane-type and ocotillol-type. ++ Compound K (CK) and new compound 20S-O-β-(D-glucosyl)-dammarenediol II (DMG) were produced in vitro in the yeast system using the identified P. ginseng glycosyltransferase (Yan et al, 2014). AACT, Acetyl-CoA C-acetyltransferase; HMGCoA, 3-hydroxy-3-methylglutaryl-CoA; HMGS, 3-hydroxy-3-methylglutaryl-CoA synthase; HMGR, 3-hydroxy-3-methylglutaryl- biosynthetic precursor for synthesizing triterpenes and phytosterols (Haralampidis et al, 2002).…”