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Toehold Switch-Based Approach for Engineering Acid-Tolerance Modules to Enhance Production Robustness of Industrial
Xin Zhang1, Xiaofang Yan1, Peng Liu1
1School of Biology and Biological Engineering, South China University of Technology, Guangzhou, Guangdong, China.
Microbial Biotechnology
|June 9, 2025
Summary
This study engineered industrial microorganisms for enhanced acid tolerance using synthetic biology. The novel toehold switch approach improved fermentation efficiency and sustainability in acid-sensitive processes.
Area of Science:
- Synthetic biology
- Industrial microbiology
- Metabolic engineering
Background:
- Industrial fermentation processes often face challenges due to low pH conditions, limiting microbial efficiency and sustainability.
- Developing acid-tolerant industrial microorganisms is crucial for optimizing fermentation outcomes and reducing operational costs.
Purpose of the Study:
- To engineer acid-tolerant industrial strains using a novel synthetic biology approach.
- To construct and evaluate a library of synthetic modules for enhanced acid resistance.
Main Methods:
- Employed a toehold switch-based system to create synthetic modules integrating acid-responsive promoters and acid-resistance genes.
- Generated a library of approximately 10^5 synthetic constructs.
- Performed stepwise evaluation to identify optimal modules (RE-6 and RE-38).
Main Results:
- Identified two highly effective synthetic modules, RE-6 and RE-38.
- Engineered lysine-producing strains maintained high titers and yields at pH 5.5, comparable to parent strains at pH 6.8.
- Transcriptional analysis confirmed upregulation of key acid-resistance genes.
Conclusions:
- The toehold switch-based approach provides a powerful tool for constructing synthetic modules to enhance microbial robustness.
- This method significantly improves acid tolerance in industrial strains, boosting fermentation efficiency and sustainability.
- The engineered strains demonstrate potential for more resilient and productive industrial applications.
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