Ciesiołka J, Lorenz S, Erdmann V A
Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznań.
Eur J Biochem. 1992 Mar 1;204(2):575-81. doi: 10.1111/j.1432-1033.1992.tb16670.x.
Lead ions have been applied to the structural analysis of 5S rRNA from Thermus thermophilus, Bacillus stearothermophilus and Escherichia coli. Based on the distribution of Pb(II)-induced cleavages, some minor modifications of the consensus secondary structure model of 5S rRNA are proposed. They include the possible base pairing between nucleotides at positions 11 and 109, as well as changes in secondary interactions within the helix B region. The 'prokaryotic arm' region is completely resistant to hydrolysis in the three RNA species, suggesting that it is a relatively stable, highly ordered structure. Hydrolysis of E. coli 5S rRNA complexed with ribosomal protein L18 shows, besides the shielding effect of the bound protein, a highly enhanced cleavage between A108 and A109. It supports the concept that the major L18-induced conformational change involves the junction of helices A, B and D.
铅离子已被应用于嗜热栖热菌、嗜热脂肪芽孢杆菌和大肠杆菌5S rRNA的结构分析。基于铅（II）诱导切割的分布情况，有人提出了对5S rRNA共有二级结构模型的一些微小修正。这些修正包括11位和109位核苷酸之间可能的碱基配对，以及螺旋B区域内二级相互作用的变化。“原核臂”区域在这三种RNA中完全抗水解，这表明它是一个相对稳定、高度有序的结构。与核糖体蛋白L18复合的大肠杆菌5S rRNA的水解显示，除了结合蛋白的屏蔽作用外，A108和A109之间的切割显著增强。这支持了主要由L18诱导的构象变化涉及螺旋A、B和D交界处的观点。
