Wang Y X, Huang S, Draper D E
Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA.
Nucleic Acids Res. 1996 Jul 15;24(14):2666-72. doi: 10.1093/nar/24.14.2666.
A conserved hairpin corresponding to nt 1057-1081 of large subunit rRNA (Escherichia coli numbering) is part of a domain targeted by antibiotics and ribosomal protein L11. The stem of the hairpin contains a U.U juxtaposition, found as either U.U or U.C in virtually all rRNA sequences. This hairpin has been synthesized and most of the aromatic and sugar protons were assigned by two-dimensional proton NMR. Distances and sugar puckers deduced from the NMR data were combined with restrained molecular dynamics calculations to deduce structural features of the hairpin. The two U residues are stacked in the helix, form one NH3-O4 hydrogen bond and require an extended backbone conformation (trans alpha and gamma) at one of the U nucleotides. The hairpin loop, UAGAAGC closed by a U-A pair, is the same size as tRNA anticodon loops, but not as well ordered.
对应于大亚基rRNA(大肠杆菌编号)第1057 - 1081核苷酸的保守发夹结构是抗生素和核糖体蛋白L11作用靶点所在结构域的一部分。该发夹结构的茎包含一个U·U并列结构,在几乎所有rRNA序列中均为U·U或U·C形式。此发夹结构已被合成,并且通过二维质子核磁共振确定了大部分芳香族和糖质子的归属。由核磁共振数据推导得出的距离和糖环构象与受限分子动力学计算相结合,以推断该发夹结构的结构特征。两个U残基在螺旋中堆积,形成一个N - H3 - O4氢键,并且在其中一个U核苷酸处需要一个延伸的主链构象(反式α和γ)。由U - A碱基对封闭的发夹环UAGAAGC,其大小与tRNA反密码子环相同,但有序程度不如tRNA反密码子环。