Engineering the MEP pathway enhanced ajmalicine biosynthesis.
The 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway genes encoding DXR and MECS from Taxus species and STR from Catharanthus roseus were used to genetically modify the ajmalicine biosynthetic pathway in hairy root cultures of C. roseus. As expected, the STR-overexpressed root cultures showed twofold higher accumulation of ajmalicine than the control. It was important to discover that overexpression of the single DXR or MECS gene from the MEP pathway also remarkably enhanced ajmalicine biosynthesis in transgenic hairy root cultures, and this suggested that engineering the MEP pathway by overexpression of DXR or MECS promoted the metabolic flux into ajmalicine biosynthesis. The transgenic hairy root cultures with co-overexpression of DXR and STR or MECS and STR had higher levels of ajmalicine than those with overexpression of a single gene alone such as DXR, MECS, and STR. It could be concluded that transgenic hairy root cultures harboring both DXR/MECS and STR possessed an increased flux in the terpenoid indole alkaloid biosynthetic pathway that enhanced ajmalicine yield, which was more efficient than cultures harboring only one of the three genes.
Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Engineering and Technology Research Centre for Sweetpotato, School of Life Sciences, Southwest University, Chongqing, People's Republic of China; Chengdu Grain Storage Research Institute, State Administration of Grain Reserves, Chengdu, People's Republic of China.
Kai
K
Chang
Fei
F
Qiu
Min
M
Chen
Lingjiang
L
Zeng
Xiaoqiang
X
Liu
Chunxian
C
Yang
Xiaozhong
X
Lan
Qiang
Q
Wang
Zhihua
Z
Liao
D019759:Carbon-Nitrogen Lyases / Q000235:genetics / Q000378:metabolism; D030008:Catharanthus / Q000201:enzymology; D004896:Erythritol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D015394:Molecular Structure; D019761:Phosphorus-Oxygen Lyases / Q000235:genetics / Q000378:metabolism; D015202:Protein Engineering; D046948:Secologanin Tryptamine Alkaloids / Q000737:chemistry / Q000378:metabolism*; D013403:Sugar Phosphates / Q000737:chemistry / Q000378:metabolism*; D020946:Taxus / Q000201:enzymology; D014166:Transferases / Q000235:genetics / Q000378:metabolism
C114232:2-C-methylerythritol 4-phosphate; D046948:Secologanin Tryptamine Alkaloids; D013403:Sugar Phosphates; C005709:raubasine; D014166:Transferases; C109461:deoxyxylulose-5-phosphate synthase; D019759:Carbon-Nitrogen Lyases; C022684:strictosidine synthetase; D019761:Phosphorus-Oxygen Lyases; D004896:Erythritol
Catharanthus roseus; DXR; MECS; STR; alkaloids; pathway engineering