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Aptamer-Based Target Detection Facilitated by a 3-Stage G-Quadruplex Isothermal Exponential Amplification Reaction
Published on: October 6, 2022
A Highly Thermostable Heme-G-Quadruplex DNAzyme: Structural Integrity and Catalytic Function Under
Daiki Fukasawa1, Ryo Karita1, Yuri Shokaku1
1Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki, Japan.
Chembiochem : a European Journal of Chemical Biology
|July 24, 2026
Summary
Engineered heme-G-quadruplex DNAzymes with more stacked G-quartets show enhanced thermal stability. These robust DNAzymes maintain catalytic activity up to 90°C, outperforming protein peroxidases.
Area of Science:
- Biochemistry
- Molecular Biology
- Catalysis
Background:
- Heme-G-quadruplex DNAzymes are promising catalysts but their stability at high temperatures is unclear.
- Understanding structural stability is crucial for their application in demanding conditions.
Purpose of the Study:
- To investigate the relationship between G-quadruplex structure and thermal stability in heme-G-quadruplex DNAzymes.
- To engineer a highly thermostable DNAzyme with improved catalytic function at elevated temperatures.
Main Methods:
- Systematic construction of heme-G-quadruplex DNAzymes with varying numbers of stacked G-quartets.
- Assessment of structural stability and peroxidase activity at elevated temperatures (up to 90°C).
Main Results:
- Increasing consecutively stacked G-quartets significantly enhances the thermal robustness of heme-G-quadruplex DNAzymes.
- The engineered DNAzyme retained high peroxidase activity up to 90°C.
- Achieved thermal stability far exceeds that of conventional protein-based peroxidases.
Conclusions:
- G-quadruplex engineering is a viable strategy for creating highly thermostable DNAzymes.
- Rational design based on G-quartet stacking can yield robust biocatalysts for high-temperature applications.
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