远离活性部位的三级接触物主要是催化剂的 ribozyme
Monika Martick1, William G Scott
1Department of Molecular, Cellular and Developmental Biology, Robert L. Sinsheimer Laboratories, University of California, Santa Cruz, Santa Cruz, CA 95064, USA.
Cell
|July 25, 2006
概括
Schistosoma mansoni头核酶的新晶体结构揭示了远程三级相互作用如何增强催化剂的1000倍. 这一发现解决了对 ribozyme 活性有矛盾的机制解释.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 头核酶是具有复杂催化机制的关键RNA酶.
- 之前使用晶体学和生物化学分析的研究为头核糖酶催化产生了相互矛盾的解释.
研究的目的:
- 阐明全长的Schistosoma mansoni头 ribozyme的催化增强的结构基础.
- 调和头核糖酶活性矛盾的机制模型.
主要方法:
- 用2.2A分辨率的X射线晶体学来确定全长的子头 ribozyme 的结构.
- 生物化学分析与结构数据相结合.
主要成果:
- 晶体结构揭示了远离活性部位的三级相互作用,这些相互作用对催化非常重要.
- 特定的核酸位 (G-12,G-8) 支持提议的酸催化作用.
- 该结构澄清了核和分裂酸盐的对齐,解释了催化效率.
- 发现了一种新的折叠,适应了以前的实验发现,并解释了以前不清楚的核酸作用.
结论:
- 呈现的结构为头核糖酶催化提供了一个统一而明确的解释.
- 三级相互作用在原始化 ribozyme 增强催化活性方面发挥着重要作用.
- 这项工作解决了对头 рибо酶的机制理解中长期存在的差异.
相关概念视频
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The term ribozyme is used for RNA that can act as an enzyme. Ribozymes are mainly found in selected viruses, bacteria, plant organelles, and lower eukaryotes. Ribozymes were first discovered in 1982 when Tom Cech’s laboratory observed Group I introns acting as enzymes. This was shortly followed by the discovery of another ribozyme, Ribonulcease P, by Sid Altman’s laboratory. Both Cech and Altman received the Nobel Prize in chemistry in 1989 for their work on ribozymes.
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