相关实验视频
Updated: May 18, 2026

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Chemical Triphosphorylation of Oligonucleotides
Published on: June 2, 2022
一般的酸催化,由核基介导,在毛里博酶中的核基
Stephanie Kath-Schorr1, Timothy J Wilson, Nan-Sheng Li
1Cancer Research UK, Nucleic Acid Structure Research Group, MSI/WTB Complex, The University of Dundee, Dow Street, Dundee DD1 5EH, UK.
Journal of the American Chemical Society
|September 11, 2012
概括
发针的 ribozyme 是一个发针.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 在RNA催化过程中.
背景情况:
- 毛核糖酶介导的RNA裂变/结合的催化机制尚未完全理解.
- 实验证据表明,氨酸 (A38) 和关氨酸 (G8) 在催化过程中的作用.
- 之前的假设提出了这些残留物的一般酸催化.
研究的目的:
- 为了阐明毛针 ribozyme 的催化机制.
- 为了研究腺素 (A38) 和关氨酸 (G8) 在RNA基结裂中的作用.
- 为了确定A38和G8在一般酸催化中是否起作用.
主要方法:
- 头发 рибо酶残留物A38和G8的局部定向突变发生.
- 合成RNA基质与一个5'-pro-thiosulfate (5'-PS) 离开组.
- 在一系列的pH值中对裂变速率的动态分析.
主要成果:
- 用纯素 (A38P) 替换A38降低了裂变速率,这被5'-PS修改所逆转.
- 通过A38P ribozyme对5'-PS基质的裂变速率显示了与一般酸性催化剂一致的pH依赖性.
- 用二氨基氨酸替代G8导致了pH依赖的裂变速率,这表明了一般基质催化剂.
结论:
- 实验数据强烈支持一种一般的酸催化机制,用于毛 ribozyme.
- 氨酸 (A38) 可能起到一般酸催化剂的作用.
- 关氨酸 (G8) 很可能在毛 ribozyme 机制中起到一般基催化剂的作用.
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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