Pulsed FT-NMR double resonance studies of yeast tRNAPhe: specific nuclear Overhauser effects and reinterpretation of low temperature relaxation data.
Pulsed FT-NMR double resonance studies of yeast tRNAPhe: specific nuclear Overhauser effects and reinterpretation of low temperature relaxation data.
复制标题
酵母 tRNAPhe 的脉冲 FT-NMR 双共振研究：特定核奥弗豪瑟效应和低温弛豫数据的重新解释。
作者：
P. D. Johnston;A. Redfield
交叉弛豫效应被证明之间的亚氨基质子和其他质子在酵母tRNAPhe和H2O。一个详细的检查已经从DSS作为溶剂中的D2O含量的函数在11.8 ppm处观察到的质子共振的弛豫速率。这一结果，以及所观察到的核Overhauser效应的大小和数量，表明溶剂H2O，氨基，亚氨基和其他tRNA质子之间的偶极磁化转移可能在低温下主导亚氨基质子的弛豫过程。在较高的温度下，所观察到的弛豫速率主要是由化学交换。选择性的核Overhauser效应被证明是一个重要的援助共振分配。通过这些方法，我们能够从摆动碱基对GU4中识别出11.8ppm和10.4ppm的两个质子。
Cross-relaxation effects are demonstrated between the imino protons and other protons in yeast tRNAPhe and H2O. A detailed examination has been made of the observed relaxation rate of the proton resonance at 11.8 ppm from DSS as a function of the D2O content in the solvent. This result, as well as the size and number of observed nuclear Overhauser effects, suggests that dipolar magnetization transfer between solvent H2O, amino, imino, and other tRNA protons may dominate the relaxation processes of the imino protons at low temperature. At higher temperatures the observed relaxation rate is dominated by chemical exchange. The selective nuclear Overhauser effects are shown to be an important aid in resonance assignments. By these means we were able to identify tow protons from the wobble base pair GU4 at 11.8 ppm and 10.4 ppm.