Biopolym. Cell. 1987; 3(2):72-76.
Structure and Function of Biopolymers
Polyelegtrolyte properties of DNA: activation energy of conductivity and conductometric melting curves of concentrated salt-free solutions
1Kuznetsov I. A., 1Apolonnik N. V., 1Shklover I. S.
  1. M. V. Lomonosov State University
    Moscow, USSR


Three linear regions on the dependence of specific conductivity of native NaDNA on the temperature in the Arrhenius coordinates are found. These regions of conductometric curve are attributed to the conductivity of native, denatured DNA and to the intermediate structure. The activation energy (Ea) independence on polyion structure is shown. The Ea values for native and denatured NaDNA are found to be equal to 16.4В±1.1 kJ/mole. A share of counterions eliminating with denaturation is approximately evaluated. It is proposed to use conductometry for the obtaining of melting curves of DNA in the concentrated salt-free solutions.


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