High resolution phosphorus NMR spectroscopy of transfer ribonucleic acids.
High resolution phosphorus NMR spectroscopy of transfer ribonucleic acids.
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转移核糖核酸的高分辨率磷核磁共振波谱。
DOI：
10.1007/bf00236777
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发表时间：
1982
影响因子：
4.3
通讯作者：
Goldfield,EM
中科院分区：
文献类型：
--
作者：
Gorenstein,DG;Goldfield,EM
酵母苯丙氨酸tRNA，E的31P NMR谱的温度依赖性。提供了 colityrosine、谷氨酸 (2) 和甲酰甲硫酮 tRNA，以及牛肝天冬氨酸 (2b) tRNA。不同受体tRNA的31P NMR谱之间的主要差异在于-0.5和-1.3 ppm之间的主簇区域。这证实了早期将主簇区域分配给发夹环和螺旋茎中未扭曲的磷酸二酯。此外，所有 tRNA 的 31P NMR 谱显示，除了低场末端 3'-磷酸单酯外，～16 个非螺旋二酯信号分布在～7 ppm 范围内。在 10 mM Mg++ 存在的情况下，大多数分散的和主要的簇信号不会在 22 至 66 °C 之间移动，从而支持我们之前的假设，即 31 P 化学位移对磷酸酯扭转和键角敏感。在 >70° 时，所有信号合并为单个随机卷曲构象信号。测量的 tRNAPhere 的自旋晶格和自旋-自旋弛豫时间揭示了除热变性过程之外与反密码子环构象变化相关的另一个较低温度转变。由于这种构象转变，在 Mg++ 存在的情况下，许多分散峰在 22 至 66 °C 之间发生偏移 (0.2–1.7 ppm) 并变宽。 Mg++和Mn++离子对tRNAPhe的31P NMR谱的影响已被用来从主簇信号中识别一些上场和下场的散射信号。酵母tRNAPhe和E之间形成的二聚体的31P NMR谱。报道了 colitRNAGlu2。该二聚体模拟密码子-反密码子相互作用，因为两个 tRNA 的反密码子三联体是互补的。有证据表明反密码子-反密码子相互作用改变了反密码子构象并部分破坏了 tRNA 的三级结构。
The temperature dependence of the31P NMR spectra of yeast phenylalanine tRNA,E. colityrosine, glutamate (2), and formylmethione tRNA, and bovine liver aspartate (2b) tRNA is presented. The major difference between the31P NMR spectra of the different acceptor tRNAs is in the main cluster region between −0.5 and −1.3 ppm. This confirms earlier assignment of the main cluster region to the undistorted phosphate diesters in the hair-pin loops and helical stems. In addition the 31P NMR spectra for all tRNAs reveal ∼16 non-helical diester signals spread over ∼7 ppm besides the downfield terminal 3′-phosphate monoester. In the presence of 10 mM Mg++, most scattered and main cluster signals do not shift between 22 and 66 °C, thus supporting our earlier hypothesis that31P chemical shifts are sensitive to phosphate ester torsional and bond angles. At >70°, all of the signals merge into a single random coil conformation signal. Measured spin-lattice and spin-spin relaxation times for tRNAPhereveal another lower temperature transition associated with a conformational change of the anticodon loop besides the thermal denaturation process. A number of the scattered peaks are shifted (0.2–1.7 ppm) and broadened between 22 and 66 °C in the presence of Mg++as a result of this conformational transition. The effects Mg++and Mn++ions on the31P NMR spectra of tRNAPhehave been used to identify some of the scattered signals upfield and downfield from the main cluster signals. The31P NMR spectrum of the dimer formed between yeast tRNAPheandE. colitRNAGlu2is reported. This dimer simulates codon-anticodon interaction since the anticodon triplets of the two tRNAs are complementary. Evidence is presented that the anticodon-anticodon interaction alters the anticodon conformation and partially disrupts the tertiary structure of the tRNA.