Wool I G, Glück A, Endo Y
Department of Biochemistry and Molecular Biology, University of Chicago, IL 60637.
Trends Biochem Sci. 1992 Jul;17(7):266-9. doi: 10.1016/0968-0004(92)90407-z.
The ribotoxins alpha-sarcin and ricin catalyse covalent modifications in adjacent nucleotides in 28S rRNA, yet the elements of nucleic acid structure that they recognize are not only different but incompatible. This suggests that this ribosomal domain (which in two dimensions is a seven-base-pair helical stem and a 17-member single-stranded loop) has alternate conformers. Since the domain is involved in binding of aminoacyl-tRNA and GTP hydrolysis, we propose that the switch between the two configurations, perhaps initiated by the binding of elongation factors, plays a role in translocation.
核糖体毒素α-肌动蛋白和蓖麻毒素催化28S核糖体RNA中相邻核苷酸的共价修饰，但它们识别的核酸结构元件不仅不同，而且相互不兼容。这表明该核糖体结构域（在二维结构中是一个七碱基对的螺旋茎和一个由17个成员组成的单链环）具有交替构象。由于该结构域参与氨酰-tRNA的结合和GTP水解，我们提出两种构型之间的转换，可能由延伸因子的结合引发，在转位过程中起作用。
