The Activation of Arginyl Transfer Ribonucleic Acid Synthetase by Transfer Ribonucleic Acid

The arginine-activating enzyme of Escherichia coli requires transfer ribonucleic acid (tRNA) for catalysis of the ATP-pyrophosphate exchange reaction. Only the specific arginine-accepting tRNA is effective, and the terminal adenylic acid residue is essential for the reaction. A previously described isotope-trapping experiment led to the suggestion that an arginyl-tRNA ester was not formed during the pyrophosphate exchange. The specific tRNA has now been shown to be required for reaction of this enzyme system with hydroxylamine and for the enzymatic pyrophosphorolysis of arginyl adenylate.