Escherichia coli tRNAAsp recognition mechanism differing from that of the yeast system

Abstract Various tRNA transcripts were constructed to study the identity elements of Escherichia coli tRNA Asp . Base substitutions from G 34 to U 34 at the first position of the anticodon, and from U 35 to A 35 at the second, severely impaired the aspartate charging activity. The activity was also decreased, but in a more moderate fashion, by base changes at G 2 -C 71 , C 36 and C 38 . Identity nucleotides of tRNA Asp are distributed in a different fashion between E. coli and yeast, which occur at the second base pair of the acceptor stem, G 10 -U 25 base pair in the D-stem and 3′ half of the anticodon loop.