The site of the inhibitory action of salicylate on protein biosynthesis <i>in vitro</i>

Abstract

Abstract Salicylate (10 mm) affects neither the transfer of the amino-acid from leucyl-tRNA into protein by rat liver polysomes nor the formation of the leucyl-tRNA. However, lower concentrations of salicylate inhibit the activities of other aminoacyl-tRNA synthetases. The most sensitive enzymes are those which incorporate glutamate, aspartate and histidine. It is suggested that salicylate interferes with the in vitro biosynthesis of protein by preferentially inhibiting the production of certain aminoacyl-tRNA species. The drug, in concentrations of 0·6 mm and above, inhibits the ATP-pyrophosphate exchange reaction promoted by individual amino-acids, including leucine.