在头核糖酶催化过程中C3和G8位置的突变效应的起源来自分子动力学模拟
1Consortium for Bioinformatics and Computational Biology, and Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|May 16, 2008
概括
分子动力学模拟揭示了头核糖酶机制. G8:2'OH组作为一般的酸催化剂,由G8和C3.3之间的沃森-克里克键稳定.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 计算化学的计算化学
背景情况:
- 头核糖酶是催化RNA分子,对于自我分裂至关重要.
- 了解它们的反应机制是RNA生物学和治疗开发的关键.
- 以前的研究表明,特定残留物在催化中起着作用,但详细的原子洞察力有限.
研究的目的:
- 通过分子动力学模拟,阐明头 ribozyme 的催化机制.
- 研究特定突变 (C3U,G8A,G8I) 对 ribozyme 活性和结构的影响.
- 提供原子级细节,以支持涉及G8:2'OH.的一般酸催化模型.
主要方法:
- 进行了十次60 ns分子动力学 (MD) 模拟.
- 模拟原生和突变的全长头核酶.
- 包括反应物和激活的前体状态 (G8:2'OH脱质).
主要成果:
- 确定了G8:2'OH组作为一般的酸催化剂.
- 证明了G8和C3之间的沃森-克里克键稳定了催化剂G8:2'OH.
- 观察到与此拟议机制一致的突变效应,包括C3U/G8A双突变的实验性救援效应.
结论:
- 通过一般酸催化,G8:2'OH组在头 рибо酶催化中发挥着关键作用.
- 在G8和C3之间,沃森-克里克的键对于定位催化剂G8:2'OH至关重要.
- 模拟MD提供了对突变效应的宝贵见解,并支持拟议的催化机制.
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...
Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
Point and Frameshift Mutations
Point mutations are genetic alterations involving the change of a single nucleotide base pair in DNA. Depending on how the alteration affects protein synthesis, they can lead to various consequences.Point mutations fall into the following types:Silent mutations occur when a nucleotide change does not alter the amino acid sequence due to the redundancy of the genetic code. For instance, changing ACC to ACA still encodes threonine, leaving the protein function unaffected. This occurs because...

