Aminoacylation of Bisulphite-modified Yeast Tyrosine Transfer RNA

AS part of a search for the chemical rules underlying the recognition of a tRNA by its aminoacyl-tRNA ligase¹, we are examining the effect of C?U transitions on aminoacylation of tRNA. In this paper, we describe four well-characterized modifications of yeast tRNA^Tyr induced by reaction with bisulphite ions at pH 5.8. Three of the observed changes proved to be C-?U transitions produced by the series of reactions shown in Fig. 1 (refs. 2–5).