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Updated: Jun 20, 2026
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A New Screening Method for the Directed Evolution of Thermostable Bacteriolytic Enzymes
Published on: November 7, 2012
Rational Engineering of a GH18 Chitinase for Enhanced Thermostability and Catalytic Efficiency via Dynamic Allosteric
Xingyue Wang1, Jianrong Chen2, Liyan Yang2
1School of Mathematics and Statistics, Guilin University of Technology, Guilin 541004, China.
Journal of Agricultural and Food Chemistry
|June 19, 2026
Summary
Computational engineering of chitinases focused on the insertion domain (CID) successfully enhanced both stability and catalytic efficiency. This strategy improved enzyme performance, offering a novel approach for enzyme optimization.
Area of Science:
- Biochemistry
- Enzyme Engineering
- Computational Biology
Background:
- Engineering chitinases for improved catalytic efficiency and thermostability is difficult.
- The insertion domain (CID) is a noncatalytic auxiliary region in chitinases.
Purpose of the Study:
- To develop a computational strategy for enhancing chitinase performance by targeting the CID.
- To identify mutations that improve both thermostability and catalytic activity.
Main Methods:
- Utilized folding free energy calculations to identify stabilizing mutations in the CID.
- Employed evolutionary coupling analysis and stability predictions to guide secondary mutation design.
- Tested engineered variants for thermostability and catalytic activity.
Main Results:
- A mutation (A347P) in the CID hydrophobic core significantly enhanced thermostability.
- Engineered double mutants showed up to 99% increase in specific activity compared to wild-type.
- The best variant (A347P/A137S) increased GlcNAc production by 4.9-fold during colloidal chitin hydrolysis.
- Mutants exhibited substantially prolonged half-lives at elevated temperatures (45 °C and 50 °C).
Conclusions:
- Targeting the CID is an effective strategy for optimizing multidomain chitinases.
- This approach successfully improved both catalytic efficiency and thermostability simultaneously.
- The engineered chitinases show potential for industrial applications requiring robust enzyme activity.
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