Development and Identification of Thermostable Tryptophanase Based on Ancestral Sequence Analysis
Yulei Zhang1,2, Yun Li1, Heng Hu1
1Anhui Provincial Key Laboratory of Molecular Enzymology and Mechanism of Major Metabolic Diseases, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, People's Republic of China.
Journal of Agricultural and Food Chemistry
|May 26, 2026
Summary
A novel, highly thermostable tryptophanase (TnaA) enzyme from Morganella morganii was discovered. This enzyme offers improved stability and activity, making it ideal for industrial indole production.
Area of Science:
- Biochemistry
- Enzymology
- Protein Engineering
Background:
- Indole and its derivatives are crucial in flavor, fragrance, and pharmaceutical industries.
- Tryptophanase (TnaA) is key for indole production from L-tryptophan, but its industrial use is limited by poor thermostability.
- A thermostable TnaA from Morganella morganii presents a potential solution.
Purpose of the Study:
- To identify and characterize a thermostable TnaA enzyme from Morganella morganii.
- To evaluate its potential as a biocatalyst for industrial indole synthesis.
Main Methods:
- Ancestral sequence analysis, structural prediction, and molecular dynamics simulations were used to identify the enzyme.
- Enzyme activity, optimal conditions (temperature and pH), and thermostability were assessed.
- Comparison with Proteus vulgaris TnaA was performed.
Main Results:
- The Morganella morganii TnaA enzyme exhibits optimal activity at 55 °C and pH 8.0.
- It demonstrates significantly enhanced thermostability compared to Proteus vulgaris TnaA, with higher Tm, T50^30, and half-life.
- The enzyme showed specificity for L-tryptophan and L-serine.
Conclusions:
- Morganella morganii TnaA is a highly thermostable enzyme with potential for industrial applications.
- Its enhanced stability makes it a promising biocatalyst for efficient and stable indole production.
Keywords:
ancestral sequence analysisindole biosynthesissubstrate specificitythermostabilitytryptophanaseMore Related Videos
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