Effects of pressure on the helix-coil transitions of the poly A-poly U system

Studies were made of the influence of hydrostatic pressure on the helix–coil transitions of poly (A + U) and poly (A + 2U). The results were analyzed by a thermodynamic treatment which emphasized the cooperative aspect of the transitions. The helix-to-coil volume changes were found to be small and negative indicating pressure stabilization of the coil form. The significance of the results with respect to other denaturation measurements was discussed.