DETERMINATION OF STABILITY OF DNA DOUBLE HELIX IN AN AQUEOUS MEDIUM

The possibility of determining the free energy of stabilization ΔG0 of native DNA structure with the help of calorimetric data on heats ΔH of transition from the native to denaturated state is considered. Results of microcalorimetric measurements of heats of denaturation of T2 phage DNA at, different values of pH and ionic strength of solution are given. Values of free energy of stabilization of the DNA native structure ΔG0 under various conditions have been obtained. It is shown that under conditions close to physiological ΔG0 approaches 1200 cal/mole per base pair. Copyright © 1969 John Wiley & Sons, Inc.