The effect of charges on the melting of DNA

Abstract A method of calculating both the electrostatic free energy and en tlpy changes for melting of DNA is proposed. The nonelectrostatic parts of free energy and enthalpy changes for melting of DNA are obtained by subtracting these electrostatic free‐energy and enthalpy changes from the total free‐energy and enthalpy changes of melting reported by Privalov, Ptitsyn, and Birshtein, respectively. The ionic strength dependence of the melting temperature of DNA is computed using these thermodynamic functions.