Srinivasan A R, Olson W K
Nucleic Acids Res. 1980 May 24;8(10):2307-29. doi: 10.1093/nar/8.10.2307.
A series of conformation wheels is constructed from the recently refined X-ray crystallographic data of monoclinic and orthorhombic yeast tRNAPhe. These circular plots relate the primary chemical structure (i.e., base sequence) directly to the secondary and tertiary structure of the molecule. The circular sequence of backbone torsion angles displays a unique pattern that is useful both in distinguishing the ordered and disordered regions of the molecule and in comparing the three sets of experimental data. Composite conformation wheels describe the fluctuations in the "fixed" parameters (phi', phi, chi) and independent conformation wheels reveal the changes in the "variable" parameters (omega', omega, psi, psi') of the three different yeast tRNAPhe models. Additional plots of base-stacking parameters help to visualize the intimate interrelationship between chemical sequence and three-dimensional folding of yeast tRNAPhe. The composite data illustrate several conformational schemes that position the bases of adjacent nucleosides in a parallel stacked array and reveal an even larger number of conformations that introduce bends or turns in the polynucleotide chain.
一系列构象轮是根据最近精修的单斜晶系和正交晶系酵母苯丙氨酸tRNA的X射线晶体学数据构建的。这些圆形图将一级化学结构(即碱基序列)直接与分子的二级和三级结构联系起来。主链扭转角的圆形序列显示出一种独特的模式,这在区分分子的有序和无序区域以及比较三组实验数据方面都很有用。复合构象轮描述了“固定”参数(φ'、φ、χ)的波动,独立构象轮揭示了三种不同酵母苯丙氨酸tRNA模型的“可变”参数(ω'、ω、ψ、ψ')的变化。碱基堆积参数的附加图有助于直观地显示酵母苯丙氨酸tRNA的化学序列与三维折叠之间的密切相互关系。综合数据说明了几种构象方案,这些方案将相邻核苷的碱基定位在平行堆积阵列中,并揭示了更多在多核苷酸链中引入弯曲或转折的构象。