No Arginyl Adenylate Is Detectable as an Intermediate in the Aminoacylation of tRNAArg

On the supposition that aminoacyl adenylate is a necessary intermediate in the reactions catalyzed by aminoacyl-tRNA synthetases, six possible reactions requiring this intermediate were tested. With arginyl tRNA synthetase from brewer's yeast they were all negative and with phenylalanyl-tRNA synthetase they were all positive. Therefore, no evidence for the formation of arginyl adenylate could be provided. This is in contrast to results published elsewhere. It was shown that the reaction proceeds through a quaternary complex. The aminoacylation of the tRNA is followed by a rearrangement of the quaternary complex that also affects the structure of the arginyl-tRNA.