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Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
寒冷变质的子头 ribozyme 的冷变质
Peter J Mikulecky1, Andrew L Feig
1Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, USA.
Journal of the American Chemical Society
|February 7, 2002
概括
在核酸中以前没有观察到的冷变性,在头核酶中得到了证明. 这一发现强调了热容量差异在RNA和DNA折叠的热力学中的重要性.
科学领域:
- 生物化学 生物化学
- 热力学是一种热力学.
- 分子生物学分子生物学
背景情况:
- 冷变性是一种已知的蛋白质热力学现象,归因于折叠和展开状态之间的热容量差异.
- 由于核酸的折叠热容量 (DeltaCp) 是可以忽略不计的,因此假定核酸中没有这种现象.
研究的目的:
- 为了研究核酸中冷变质的潜力.
- 为了确定头 ribozyme 的低温结构行为.
主要方法:
- 循环二重化谱法被用来分析头核糖酶在不同温度和条件下的结构.
- 数据被安装在一个双态模型中,以计算热力学参数.
主要成果:
- 在-20°C时观察到头核糖酶的冷展开,这表明三级结构损失.
- 热和冷展开事件都发生在特定条件下,过渡温度 (Tm) 为53°C和-1°C.
- 计算的DeltaCp为3.4kJ mol-1 K-1,与DNA复杂的值保持一致.
结论:
- 这项研究提供了第一个直接证据,证明了核酸中的冷变性.
- 这些发现强调了DeltaCp在核酸折叠的热力学中的关键作用,挑战了以前的假设.
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.
Ribozymes can be...
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