Nucleotide Sequences in the Yeast Alanine Transfer Ribonucleic Acid.

The purification of the yeast alanine-, tyrosine-, and valinetransfer ribonucleic acids by countercurrent distribution has been described (l), and preliminary data have been reported on the oligonucleotide compositions of these RNAs (2, 3). The present paper summarizes results of attempts to account quantitatively for all of the fragments obtained by digestion of the alanineRNA with pancreatic RNase and with Taka-Diastase RNase Tl. Results of the analyses of these two digests are consistent, one with the other, and indicate that the alanine-RNA is composed of 77 nucleotides, including nine unusual nucleotides.