在子头 ribozyme 中探测一般基质催化
Jason M Thomas1, David M Perrin
1Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada, V6T 1Z1.
Journal of the American Chemical Society
|October 28, 2008
概括
研究人员使用亲和标签在头核酶中确定了一个关键的功能组. 这项研究表明,关氨-12 (G12) 在RNA分裂中起到一般基因催化剂的作用.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 酶学 是一种酶学.
背景情况:
- 头核糖酶是关键的RNA酶,参与RNA分裂.
- 以前的研究表明,特定的功能组参与一般/酸催化.
- 这些组在催化机制中的确切作用仍然不清楚.
研究的目的:
- 为了确定*S. mansoni*头核糖酶中的功能总基.
- 为了测试特定的 ribozyme 功能组直接参与催化作用的假设.
- 调查瓜-12 (G12) 在催化机制中的作用.
主要方法:
- 开发一种亲和度标签 (2'-乙胺),以针对一般基础.
- 头核酶与基质模拟物的反应.
- 使用足迹分析识别基化残留物.
- pH和离子 ([Mg2+]) 的依赖性研究.
主要成果:
- 证明了以pH和[Mg2+]依赖的方式对瓜-12 (G12) 的N1的化.
- 观察到的化模式与原生RNA裂变反应一致.
- 提供了证据,证明G12的无质子N1功能作为一般基质催化剂.
- 在活性部位内显示了G12的pKa向下扰动.
- 识别了pH独立的基化物,提供了对利博酶结构的洞察.
结论:
- 关氨酸-12 (G12) 直接作为头核酶催化剂的一般基因起作用.
- 活性部位结构降低了G12的pKa,促进了它的作用.
- 这项研究为头 рибо酶的催化机制提供了重要的证据.
- 我们进一步了解了 ribozyme 的构成和结构.
相关概念视频
Ribozymes
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.
Ribozymes can be...
Ribozymes can be...
Ribozymes
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.
Ribozymes can be...
Ribozymes can be...
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