通过四基因组I ribozyme ribozyme 的杂交催化
Marcello Forconi1, Daniel Herschlag
1Department of Biochemistry, B400 Beckman Center, Stanford University, Stanford, California 94305-5307, USA.
Journal of the American Chemical Society
|April 28, 2005
概括
酶可以执行多个反应,一种称为催化性乱交的特征. 这项研究表明,核糖酶可以催化与中性基质的新反应,揭示了对RNA进化的洞察力.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 生命的起源 生命的起源
背景情况:
- 催化性乱交,酶催化多个反应的能力,对于蛋白质进化新功能至关重要.
- 在早期的RNA世界里,性行为可能对发展催化多样性至关重要.
研究的目的:
- 为了研究四胺组I рибо酶的催化性乱交.
- 探索基质电荷和几何在 ribozyme 催化和进化的作用.
主要方法:
- 与中性酸盐二基基质对I组四胺 ribozyme 的活性进行表征.
- 催化效率与天然的阳离子基质和先前观察到的氨基酸转移反应的比较.
主要成果:
- 核酶表现出一种新的乱交活动,催化瓜诺辛对中性酸二的攻击.
- 这种反应被加速了大约1 x 10^6倍,明显高于氨基酸转移,但低于自然反应.
- 结果表明,电荷和几何学都对 ribozyme 的自然催化功能至关重要.
结论:
- ribozymes 中的催化散乱性可以通过基质特性,如电荷和几何学来调节.
- 随性活动可能通过RNA域重排增强,有助于催化功能的进化.
相关概念视频
Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Riboswitches
Riboswitches are non-coding mRNA domains that regulate the transcription and translation of downstream genes without the help of proteins. Riboswitches bind directly to a metabolite and can form unique stem-loop or hairpin structures in response to the amount of the metabolite present. They have two distinct regions – a metabolite-binding aptamer and an expression platform.
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
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...
Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Transcriptional Regulation: Riboswitches
Riboswitches are RNA elements that regulate gene expression by altering their secondary structures in response to specific effector molecules. These elements, located in the leader regions of certain mRNAs, act as transcriptional regulators by toggling between alternative conformations to control downstream gene expression. Riboswitch-mediated regulation is a precise mechanism for modulating biosynthetic pathways, as exemplified by the riboflavin biosynthesis pathway in Bacillus...


