Nucleoside Modifications Affect the Structure and Stability of the Anticodon of tRNALys,3

NMR spectroscopy was used to determine the solution structures of RNA oligonucleotides comprising the anticodon domain of tRNA(Lys,3). The structural effects of the pseudouridine modification at position 39 were investigated and are well correlated with changes in thermodynamic parameters. The loop conformation differs from that seen in tRNA(Phe) and provides an explanation of the critical role of modification in this tRNA.