Efficient trans-aconitic acid production using systematically metabolic engineered Escherichia coli
Leilei Guo1, Yi Cheng1, Xiaoxu Tan1
1State Key Laboratory of Microbial Technology, Shandong University, Qingdao, People's Republic of China.
Synthetic and Systems Biotechnology
|October 6, 2025
Summary
Metabolic engineering of Escherichia coli enabled de novo biosynthesis of trans-aconitic acid (TAA). The engineered strain achieved high-level TAA production, demonstrating a viable microbial platform for this versatile biochemical.
Area of Science:
- Biotechnology
- Metabolic Engineering
- Synthetic Biology
Background:
- Trans-aconitic acid (TAA) is a valuable platform biochemical with diverse industrial applications.
- Developing efficient microbial production methods for TAA is crucial for its sustainable utilization.
Purpose of the Study:
- To engineer Escherichia coli for the de novo biosynthesis of trans-aconitic acid (TAA).
- To optimize the metabolic pathways and fermentation conditions for high-yield TAA production.
Main Methods:
- Constructed a pyruvate accumulation chassis strain by deleting byproduct formation genes.
- Screened and co-expressed aconitate isomerase and TAA transporter.
- Overexpressed feedback-insensitive pyruvate carboxylase and citrate synthase, while deleting isocitrate lyase.
- Optimized fermentation conditions for the engineered E. coli strain.
Main Results:
- Achieved a TAA concentration of 37.32 g/L within 40 hours.
- Obtained a high yield of 0.76 g/g glucose and a productivity of 0.93 g/L/h.
- Demonstrated successful de novo biosynthesis of TAA in a metabolically engineered E. coli.
Conclusions:
- Metabolic engineering of E. coli is an effective strategy for TAA production.
- The developed strain and process offer a promising microbial platform for industrial TAA synthesis.
- Further optimization could lead to even higher TAA yields and productivity.
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