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Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers
Published on: September 19, 2017
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Microperoxidase-11-induced reconfiguration of G-quadruplex nanostructures
Leen Massalha1, Nurit Adiram-Filiba1, Eyal Golub1
1Department of Chemistry, Faculty of Exact Sciences, Institute of Nanotechnology and Advanced Materials, Bar Ilan University, 5290002, Israel.
International Journal of Biological Macromolecules
|June 26, 2025
Summary
Ligand binding to guanine quadruplexes (GQs) is key in DNA biotechnology. This study reveals a predictable relationship between GQ sequence, binding kinetics, and melting temperature, aiding ligand design.
Area of Science:
- Biotechnology
- Structural Biology
- Chemical Biology
Background:
- Guanine quadruplexes (GQs) are G-rich nucleic acid structures with significant roles in biotechnology.
- Ligand-mediated control of GQ secondary structure is crucial, but sequence-dependent predictability remains a challenge.
Purpose of the Study:
- To investigate the impact of guanine quadruplex (GQ) sequence identity on the kinetics of ligand binding.
- To understand how sequence influences the chaperone-like binding mechanism and subsequent sequence preference.
Main Methods:
- Monitoring the topological conversion of flexible, non-parallel GQs induced by microperoxidase-11.
- Analyzing iso-compositional groups of GQs to assess sequence effects.
Main Results:
- A linear relationship was observed between the activation energy of ligand binding and the melting temperature for individual GQ sequences within iso-compositional groups.
- This correlation holds true irrespective of the specific sequence composition or topology of the GQs.
Conclusions:
- The findings elucidate the chaperone-like binding mechanism of ligands to GQs.
- This study provides a foundation for designing ligands with enhanced sequence specificity through understanding GQ-ligand interactions.
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