A Pull-Block Metabolic Engineering Strategy for High-Yield and High-Purity Hyoscyamine Production in Atropa...

Area of Science:

• Plant Biotechnology
• Metabolic Engineering
• Pharmacognosy

Background:

• Hyoscyamine, a key tropane alkaloid from Atropa belladonna, has vital pharmaceutical uses.
• Industrial production is hindered by low yields and complex alkaloid profiles in wild-type plants.

Purpose of the Study:

• To enhance hyoscyamine yield and purity in Atropa belladonna through metabolic engineering.
• To develop glyphosate-resistant Atropa belladonna for improved cultivation and production.

Main Methods:

• Implemented a pull-block metabolic engineering strategy involving gene co-overexpression (AbPYKS, AbCYP82M3, AbUGT1, AbLS, AbHDH) and gene deletion (AbH6H).
• Introduced the glyphosate resistance gene G2-EPSPS into Atropa belladonna.
• Generated and analyzed engineered glyphosate-resistant plants.

Main Results:

• Engineered plants exhibited a significant increase in hyoscyamine yield (6.511 mg/g DW vs. 0.989 mg/g DW in leaves).
• Enhanced purity was confirmed by the absence of anisodamine and scopolamine in engineered plants.
• Successfully developed glyphosate-resistant Atropa belladonna lines.

Conclusions:

• The metabolic engineering strategy effectively enhanced hyoscyamine biosynthesis and blocked metabolic diversion.
• The developed glyphosate-resistant lines offer a promising avenue for large-scale hyoscyamine production for pharmaceuticals.
• Further field evaluations are planned to assess production and plant development under real-world conditions.