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Updated: Apr 1, 2026
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A New Screening Method for the Directed Evolution of Thermostable Bacteriolytic Enzymes
Published on: November 7, 2012
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Engineering a Substrate-Binding Chain Assisting the Balance of Thermostability and Activity Trade-Off for Esterase
Zhengwen Zhu1, Zelin Lu1, Zhongshi Huang1
1CAS Key Lab of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 88 Keling Road, Suzhou 215004, China.
Journal of Agricultural and Food Chemistry
|March 30, 2026
Summary
Enzyme engineering improved esterase stability for malathion degradation. Modifications balanced thermostability and catalytic efficiency, enabling efficient pesticide breakdown at higher temperatures.
Area of Science:
- Biotechnology
- Enzyme Engineering
- Environmental Science
Background:
- Esterases offer a green method for degrading the pesticide malathion.
- Limited thermal stability of wild-type esterases hinders their industrial use.
Purpose of the Study:
- To engineer an esterase for enhanced thermostability and efficient malathion degradation.
- To investigate strategies for balancing enzyme stability and catalytic activity.
Main Methods:
- Combinatorial engineering integrating folding energy optimization, net charge modification, and consensus design.
- Molecular dynamics simulations to understand structure-activity relationships.
- Activity assays and malathion degradation tests at elevated temperatures.
Main Results:
- Engineered esterase variants showed significant thermostability improvements.
- A double mutant (S275Y-S326M) retained 92.3% activity at 50°C but had reduced catalytic efficiency.
- A quadruple mutant (S275Y-S326M-L236K-F372K) recovered catalytic efficiency and fully degraded malathion within 25 min at 50°C.
Conclusions:
- A practical strategy was developed to balance enzyme thermostability and activity via substrate-binding-oriented design.
- The engineered esterase demonstrates potential for industrial malathion bioremediation.
- The approach may be applicable to enhancing other enzyme systems.
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