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Published on: January 15, 2018
Microbial synthesis of triacetic acid lactone
Dongming Xie1, Zengyi Shao, Jihane Achkar
1Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA.
Biotechnology and Bioengineering
|October 26, 2005
Summary
Researchers identified the best enzyme for microbial triacetic acid lactone (TAL) synthesis. A modified 6-methylsalicylic acid synthase (6-MSAS) enzyme in yeast achieved the highest TAL production, yielding 1.8 g/L.
Area of Science:
- Biotechnology
- Synthetic Biology
- Enzyme Engineering
Background:
- Microbial synthesis of valuable compounds like triacetic acid lactone (TAL) is a key area in biotechnology.
- Identifying optimal enzymes and microbial hosts is crucial for efficient bioproduction.
Purpose of the Study:
- To evaluate and compare different enzymes for TAL synthesis.
- To optimize the microbial host and expression conditions for enhanced TAL production.
Main Methods:
- Expression of native 2-pyrone synthase (2-PS), mutant fatty acid synthase B (FAS-B), and 6-methylsalicylic acid synthase (6-MSAS) in Saccharomyces cerevisiae.
- Genetic modification of ketoreductase domains in FAS-B and 6-MSAS.
- Optimization of promoter selection (P(ADH2)) and microbial cultivation.
Main Results:
- Saccharomyces cerevisiae showed higher expression levels of 2-PS compared to Escherichia coli.
- The Y1572F mutant of 6-MSAS demonstrated the highest TAL-synthesizing activity.
- Maximal TAL concentration of 1.8 g/L and yield of 6% were achieved using the Y1572F mutant of 6-MSAS.
Conclusions:
- Engineered 6-MSAS, specifically the Y1572F mutant, is the most effective enzyme for microbial TAL production in S. cerevisiae.
- Optimized expression systems in S. cerevisiae are suitable for efficient biosynthesis of TAL.
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