Figure 5.
CID-MS/MS spectrum of [AUUUAm2G]2− derived from RNase T1 digestion of yeast tRNAPhe−1. The doubly charged ion with m/z = 966.6 was analyzed by CID. The nucleotide sequence was verified by manual interpretation of the a- and c-type (normal text) and w- and y-type (italic text) product ion series as indicated in the figure. The parent ion losing methyl guanine [P−B(mG)2−], the parent ion losing adenine [P−B(A)2−], the y5 ion losing methyl guanine [y5−B(mG)2−], the y5 ion losing adenine [y5−B(A)2−], y52− and c52− were doubly charged products. All other assigned signals were singly charged products, unless indicated otherwise. The asterisks indicate hydrated or dehydrated ions of a-, c-, w- or y-type products.