Stretching of a single-stranded DNA: Evidence for structural transition

Abstract

Recent experiments have shown that the force-extension (F-x) curve for single-stranded DNA (ssDNA) consisting only of adenine [poly(dA)] is significantly different from thymine [poly(dT)]. Here, we show that the base stacking interaction is not sufficient to describe the F-x curves as seen in the experiments. A reduction in the reaction co-ordinate arising from the formation of helix at low forces and an increase in the distance between consecutive phosphates of unstacked bases in the stretched state at high force in the proposed model, qualitatively reproduces the experimentally observed features. The multi-step plateau in the F-x curve is a signature of structural change in ssDNA.

10 pages, 4 figures

References in corpus (3)

• The Effects of Stacking on the Configurations and Elasticity of Single Stranded Nucleic Acids
• Collapse Transition of Two-Dimensional Flexible and Semiflexible Polymers
• Effects of Eye-phase in DNA unzipping

Cited by in corpus (6)

• Sequence-dependent thermodynamics of a coarse-grained DNA model
• The probability analysis of opening of DNA
• Mesoscopic models for DNA stretching under force: new results and comparison to experiments
• Statistical Mechanics of DNA Rupture: Theory and Simulations
• Stretching force dependent transitions in single stranded DNA
• Stretching self-interacting, partially directed, flexible and semi-flexible polymers by an external force