Coarse-grained simulations of DNA overstretching.

  title={Coarse-grained simulations of DNA overstretching.},
  author={Flavio Romano and Debayan Chakraborty and Jonathan P. K. Doye and Thomas E. Ouldridge and Ard A. Louis},
  journal={The Journal of chemical physics},
  volume={138 8},
We use a recently developed coarse-grained model to simulate the overstretching of duplex DNA. Overstretching at 23 °C occurs at 74 pN in the model, about 6-7 pN higher than the experimental value at equivalent salt conditions. Furthermore, the model reproduces the temperature dependence of the overstretching force well. The mechanism of overstretching is always force-induced melting by unpeeling from the free ends. That we never see S-DNA (overstretched duplex DNA), even though there is clear… 

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