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用ＮＭＲ谱研究了溶液中镧离子对苯丙氨酸转移核糖核酸（简称ｔＲＮＡＰｈｅ）结构和构象变化的影响。研究表明Ｌａ３＋对ｔＲＮＡＰｈｅ亚胺质子范围的１ＨＮＭＲ谱具有特殊的影响，位于扩大二氢尿嘧啶螺旋（Ｄ螺旋）的端梢三级碱基对Ｇ１５·Ｃ４８明显受Ｌａ３＋的影响（向低场位移０３５）；堆积在Ｇ１５·Ｇ４８上的Ｕ８·Ａ１４碱基对在存有１～２个Ｍｇ２＋时亦受Ｌａ３＋的影响。酵母ｔＲＮＡＰｈｅ中可能受到Ｌａ３＋影响的另一亚胺质子为Ｇ１９·Ｃ５６三级碱基对，由于Ｇ１９·Ｃ５６的亚胺质子共振位于高度叠加的１２６～１２２之间。该碱基对有助于Ｄ环对ＴΨＣ环的联接。Ｌａ３＋引起ｔＲＮＡ分子构象的变化并且导致一些谱峰向高场或低场位移。
The effect of lanthanum ion on the structure and conformation of p-phenylalanine transfer ribonucleic acid (tRNAPhe) was studied by NMR spectroscopy. Studies have shown that La3 + has a special impact on the 1HNMR spectrum of the tRNAPhe imine proton, located at the end of the enlarged dihydrouracil (D-helix) tertiary base G15 · C48 significantly affected by La3 + 035). The U8 · A14 base pairs deposited on G15 · G48 were also affected by La3 + in the presence of 1 ~ 2 Mg2 +. The other imine proton that may be affected by La3 + in yeast tRNAPhe is G19 · C56 tertiary base pairs, and the imine proton resonance of G19 · C56 is located between 12.6 ~ 12.2 superposition. The base pairs help D ring T Ψ C ring connection. La3 + causes a change in the conformation of the tRNA molecule and results in the shift of some of the spectral peaks to high or low field.