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Simulating the Helicase Enzymatic Action on ds-DNA: A First-Principles Molecular Dynamics Study
Angel Ivan Rodriguez-Leon1, Cristian Ordóñez2, Ruben Santamaria1
1Department of Theoretical Physics, Institute of Physics, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico.
ACS Omega
|February 10, 2025
Summary
This study reveals the mechanical forces and energy changes during double-stranded DNA unwinding, crucial for understanding DNA replication and cellular functions.
Area of Science:
- Molecular Biology
- Genetics
- Biophysics
Background:
- DNA replication is a fundamental biological process.
- Understanding DNA mechanics is key to advancements in genetics and molecular biology.
Purpose of the Study:
- To investigate the mechanical characteristics of double-stranded DNA (ds-DNA) during unwinding.
- To simulate helicase action and analyze forces, thermal fluctuations, and energy changes during base pair separation.
Main Methods:
- Simulated helicase action using Langevin and sequential/helical steering harmonic forces.
- Investigated three distinct ds-DNA molecules.
- Combined quantum mechanical techniques with an implicit force model.
Main Results:
- Detailed analysis of thermal fluctuations, energy changes, charge variations, and forces during ds-DNA unwinding.
- Quantified mechanical properties associated with each base pair separation.
Conclusions:
- The integrative approach combining quantum mechanics and implicit force models offers versatile insights into DNA mechanisms.
- Enhanced understanding of DNA replication and cellular functioning through detailed mechanical analysis.
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