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Published on: January 23, 2019
[Temperature-switched high-efficiency D-lactate production from glycerol]
Kangming Tian1, Li Zhou, Xianzhong Chen
1School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China.
Summary
This study optimized D-lactate production from glycerol using Escherichia coli. A novel temperature-switched fermentation process significantly increased D-lactate yield to 88.9%.
Area of Science:
- Biotechnology
- Metabolic Engineering
- Industrial Microbiology
Background:
- Glycerol is an abundant, underutilized raw material from oil hydrolysis.
- Escherichia coli CICIM B0013-070 is a D-lactate over-producing strain.
- Optimizing fermentation conditions is crucial for efficient bioproduct generation.
Purpose of the Study:
- Investigate glycerol metabolism and growth of E. coli at different temperatures.
- Develop a novel temperature-switched fermentation process for enhanced D-lactate production.
- Improve D-lactate yield from glycerol using metabolic engineering strategies.
Main Methods:
- Aerobic and anaerobic cultivation of E. coli on glycerol.
- Temperature-shift fermentation optimization.
- Utilizing a thermo-inducible promoter for D-lactate dehydrogenase regulation.
Main Results:
- Characterized E. coli growth and metabolism on glycerol across various temperatures.
- Achieved a D-lactate yield of 82.6% under optimized temperature-switched conditions.
- Reached a final D-lactate yield of 88.9% by regulating D-lactate dehydrogenase transcription.
Conclusions:
- The temperature-switched process significantly enhances D-lactate production from glycerol.
- Genetic regulation of D-lactate dehydrogenase further boosts yield.
- This study presents a viable strategy for sustainable D-lactate manufacturing.
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