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Updated: Aug 3, 2026
08:48
Stretching Short Sequences of DNA with Constant Force Axial Optical Tweezers
Published on: October 13, 2011
[Conformational effects of DNA stretching]
J Mazur1, R L Jernigan, A Sarai
1Advanced Biomedical Computing Center, SAIC, NCI-FCRDC, Frederick, MD 21701, USA.
Molekuliarnaia Biologiia
|May 2, 2003
Summary
Stretching DNA significantly alters base pair conformation, reversing propeller twist and unwinding the double helix. These changes in DNA flexibility are crucial for protein interactions.
Area of Science:
- Molecular Biology
- Biophysics
- Computational Chemistry
Context:
- DNA's extensible nature allows for extended conformations relevant to biological functions.
- Understanding DNA mechanics under stress is key to deciphering its role in cellular processes.
Purpose:
- To investigate the impact of elongation stress on DNA base pair conformation and flexibility.
- To analyze the conformational changes and energy landscapes of stretched DNA using computational methods.
Summary:
- Conformational analysis reveals that stretching DNA significantly affects base pair properties, notably reversing the propeller twist.
- Electrostatic interactions stabilize the positive propeller twist in stretched DNA, while helical twist decreases, unwinding the helix.
- DNA base pair fluctuations initially increase due to unstacking but decrease with further stretching due to specific interactions.
Impact:
- Stretching profoundly influences DNA flexibility and conformation, impacting its functional interactions with proteins.
- These findings provide insights into the mechanical properties of DNA and their biological relevance.
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