2'-氨基-2'-脱氧三核酸的合成和非酶型模板定向聚合
J Craig Blain1, Alonso Ricardo, Jack W Szostak
1Howard Hughes Medical Institute and Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, United States.
Journal of the American Chemical Society
|January 14, 2014
概括
研究人员合成了2'-氨基三核酸 (2'-NH2-TNA),并发现其对RNA,DNA和TNA模板的非酶复制太慢. 这种较差的动力性能可能解释了为什么2'-NH2-TNA在生命早期没有被用作遗传物质.
科学领域:
- 天体生物学与生命起源研究研究
- 合成化学和分子生物学
背景情况:
- 三核酸 (TNA) 是早期遗传材料的候选物.
- 了解TNA的能力对于生命起源理论至关重要.
研究的目的:
- 为了合成2"-氨基基基改性TNA (2-NH2-TNA) 核酸.
- 为了评估2 -NH2-TNA核酸的非酶性模板复制能力.
主要方法:
- 通过循环添加和核化,新合成2 -NH2-TNA乙胺和氨酸核化物.
- 关氨酸2 -NH2-TNA核酸的激活用于非酶原料扩展.
- 在RNA,DNA和TNA模板上添加核酸的动态分析.
主要成果:
- 在7个步骤中成功合成2 -NH2-TNA核化物.
- 核酸添加的测量伪第一阶速率常数:1.5小时-1 (RNA),0.97小时-1 (DNA),0.57小时-1 (TNA).
- 观察到激活核酸的快速水解 (0.39小时(-1)) 模板复制有限.
结论:
- 与氨基糖核糖酸相比,2-NH2-TNA的模板复制动力学显著较慢.
- 低的聚合效率表明TNA可能不是被选择的遗传材料的原因.
- 这项研究提供了关于替代核酸系统在生命早期进化的局限性的见解.
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