...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >NMR structures of r(GCA(G)under-barGC(G)under-barUGC)(2) and determinants of stability for single guanosine-guanosine base pairs
【24h】

NMR structures of r(GCA(G)under-barGC(G)under-barUGC)(2) and determinants of stability for single guanosine-guanosine base pairs

机译：R（GCA（g）欠巴氏菌（G）欠-BARUGC欠压（2）的NMR结构，以及单一鸟氨酸 - 鸟苷碱基对的稳定性的决定因素

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Nucleotides in RNA that are not Watson-Crick-paired form unique structures for recognition or catalysis, but determinants of these structures and their stabilities are poorly understood. A single noncanonical pair of two guanosines (G) is more stable than other noncanonical pairs and can potentially form pairing structures with two hydrogen bonds in four different ways. Here, the energetics and structure of single GG pairs are investigated in several sequence contexts by optical melting and NMR. The data for r(5'GCAGGCGUGC3')(2), in which G4 and G7 are paired, are consistent with a model in which G4 and G7 alternate syn glycosidic conformations in a two-hydrogen-bond pair. The two distinct structures are derived from nuclear Overhauser effect spectroscopic distance restraints coupled with simulated annealing using the AMBER 95 force field. In each structure, the imino and amino protons of the anti G are hydrogen bonded to the O6 and N7 accepters of the syn G, respectively. An additional hydrogen-bond connects the syn G amino group to the 5' nonbridging pro-R-p phosphate oxygen. The GG pair fits well into a Watson-Crick helix. In r(5'GCAGGCGUGC3')(2), the G4(anti), G7(syn) structure is preferred over G4(syn), G7(anti). For single GG pairs in other contexts, exchange processes make interpretation of spectra more difficult but the pairs are also G(syn), G(anti). Thermodynamic data for a variety of duplexes containing pairs of G, inosine, and 7-deazaguanosine flanked by GC pairs are consistent with the structural and energetic interpretations for r(5'GCAGGCGUGC3')(2), suggesting similar GG conformations. [References: 63]
机译：RNA中的核苷酸不是Watson-Cric-Cread的形式的独特结构，用于识别或催化，但这些结构的决定因素及其稳定性较差。单个非甘露糖对两个鸟苷（G）比其他非碳对更稳定，并且可以以四种不同的方式潜在地形成具有两个氢键的配对结构。这里，通过光学熔化和NMR在几个序列背景下研究单个GG对的能量和结构。 R（5'GcagGcGugc3'）（2）的数据，其中G4和G7配对，与在双氢 - 键对对中的G4和G7交替的SYN糖苷构象的模型一致。这两个不同的结构源自核传导效应光谱距离限制，其使用琥珀95力场与模拟退火相结合。在每种结构中，抗G的亚氨基和氨基质子分别与SYN g的O6和N7负接受者键合。另外的氢键将SYN G氨基连接到5'非录制Pro-R-P磷酸氧。 GG对很适合Watson-Crick Helix。在R（5'GCAGGCGugc3'）（2）中，G4（抗），G7（SYN）结构优于G4（SYN），G7（抗）。对于其他上下文的单个GG对，交换过程使光谱的解释更加困难，但对也是G（SYN），G（反）。由GC对侧翼的含量对的各种双链体的热力学数据与GC对相侧的一致性与R（5'GcagcGugc3'）（2）的结构和能量解释一致，表明类似的GG构象。 [参考：63]

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号