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Updated: Apr 16, 2026
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Analysis of Fucosylated Human Milk Trisaccharides in Biotechnological Context Using Genetically Encoded Biosensors
Published on: April 13, 2019
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High-Level Difucosyllactose Biosynthesis via Metabolic and Transporter Engineering
Lizhi Zhu1,2, Caiwen Lao3, Lixia Yuan1,2
1University of Science and Technology of China, Hefei 230026, China.
Journal of Agricultural and Food Chemistry
|April 15, 2026
Summary
This study engineered *Escherichia coli* to produce difucosyllactose (DFL), a prebiotic oligosaccharide. A record titer of 110.3 g/L was achieved through metabolic and transporter engineering, demonstrating a robust platform for industrial production.
Area of Science:
- Metabolic Engineering
- Biotechnology
- Microbial Fermentation
Background:
- Difucosyllactose (DFL) is a complex human milk oligosaccharide with significant prebiotic potential.
- Efficient biosynthesis of DFL is crucial for its industrial application.
- Existing methods for DFL production are limited in titer and efficiency.
Purpose of the Study:
- To engineer *Escherichia coli* for high-titer biosynthesis of DFL.
- To optimize the metabolic pathways and transporter systems for DFL production.
- To establish a robust platform for industrial-scale DFL manufacturing.
Main Methods:
- Engineered *Escherichia coli* using glycosyltransferases (WbgL and FutM1) for DFL synthesis.
- Optimized enzyme catalytic efficiency and gene copy numbers.
- Disrupted competing pathways (*wcaI*, *wcaH*, *nudK*) and deleted *pykA* to enhance precursor availability.
- Engineered transporters by deleting *emrE* and overexpressing *ompF*.
- Implemented continuous low-concentration lactose feeding in a 5-L bioreactor.
Main Results:
- Achieved a record-breaking DFL titer of 110.3 g/L.
- Identified optimal enzyme pair (WbgL and FutM1) and maximized their catalytic efficiency.
- Successfully redirected carbon flux and enhanced precursor availability.
- Improved synthesis efficiency through targeted transporter engineering.
- Demonstrated high-level DFL production under optimized fermentation conditions.
Conclusions:
- Systematic metabolic engineering and refined process control provide a robust platform for industrial production of complex oligosaccharides like DFL.
- The engineered *E. coli* strain and fermentation strategy represent a significant advancement in DFL manufacturing.
- This study paves the way for large-scale, cost-effective production of DFL for prebiotic applications.
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