Reversible Dissociation of Ribonucleic Acid

Abstract

THE work reported here was prompted by the observation that when infectious ribonucleic acid, isolated from Ehrlich ascites cells infected with Mengo encephalomyelitis virus¹, was incubated with crystalline bovine plasma albumin in solutions of physiological ionic strength, its biological activity was lost or sharply inhibited. No loss of infectivity was observed when mixtures of these two substances were incubated in concentrated solutions of sodium chloride (0.6–1.0 M). However, infectivity was not regained when protein–ribonucleic acid mixtures in physiological saline were made 0.64 M with respect to sodium chloride. The biological activity of the Mengo ribonucleic acid and of the Mengo ribonucleic acid–bovine plasma albumin mixtures was assayed by a plaque method employing monolayers of Earle's L strain mouse fibroblasts².