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arXiv · 0709.2958

Denaturation transition of stretched DNA

Andreas Hanke·Martha G. Ochoa·Ralf Metzler
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Abstract

We generalize the Poland-Scheraga model to consider DNA denaturation in the presence of an external stretching force. We demonstrate the existence of a force-induced DNA denaturation transition and obtain the temperature-force phase diagram. The transition is determined by the loop exponent $c$ for which we find the new value $c=4ν-1/2$ such that the transition is second order with $c=1.85<2$ in $d=3$. We show that a finite stretching force $F$ destabilizes DNA, corresponding to a lower melting temperature $T(F)$, in agreement with single-molecule DNA stretching experiments.

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Andreas Hanke, Martha G. Ochoa, Ralf Metzler. 2008-01-10. Denaturation transition of stretched DNA. https://doi.org/10.1103/physrevlett.100.018106

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