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DNA condensation and redissolution: Interaction between overcharged DNA molecules

E. Allahyarov·G. Gompper·H. Löwen
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Abstract

The effective DNA-DNA interaction force is calculated by computer simulations with explicit tetravalent counterions and monovalent salt. For overcharged DNA molecules, the interaction force shows a double-minimum structure. The positions and depths of these minima are regulated by the counterion density in the bulk. Using two-dimensional lattice sum and free energy perturbation theories, the coexisting phases for DNA bundles are calculated. A DNA-condensation and redissolution transition and a stable mesocrystal with an intermediate lattice constant for high counterion concentration are obtained.

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E. Allahyarov, G. Gompper, H. Löwen. 2005-01-21. DNA condensation and redissolution: Interaction between overcharged DNA molecules. https://doi.org/10.1088/0953-8984%2F17%2F20%2F012

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