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在tRNA受体干部上吊模拟器中进行跨链氨基基转移

Long-Fei Wu¹, Meng Su¹, Ziwei Liu¹

¹MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, United Kingdom.

Journal of the American Chemical Society

|July 20, 2021

概括

早期的RNA分子可能是非酶化的氨基酸. 这项研究显示了氨基酸对RNA的有效,立体选择性转移,这表明蛋白质合成前氨基酸tRNA生成的前生物途径.

科学领域:

生命的起源研究
RNA世界假设
前生物化学

背景情况:

基因编码的合成需要氨基tRNA.
必须有一个早期的非蛋白质催化方法来生成氨基酸tRNA.
了解这种前生物过程是了解早期生命演变的关键.

研究的目的:

展示一种非蛋白质催化生成氨基酸tRNA的方法.
研究氨基酸转移到RNA模拟物的效率和立体选择性.
为了探索一种潜在的益生菌氨基化途径.

主要方法:

合成的氨基酸混合无水化物.
使用的tRNA受体干模仿了3'-重挂.
研究的链间氨基酸转移到模拟RNA的2',3'-二醇末端.

主要成果:

从氨基酸混合无水化物向RNA模拟物进行有效的链间氨基酸转移.
观察到L-alanyl转移的高立体选择性 (比D-alanyl大约10:1),具有特定的突起.
显示N-acyl-aminoacyl残留物也转移,效率和立体选择性取决于悬浮序列和长度.

结论:

RNA分子可以以立体选择和化学选择的方式自发氨基基化.
这种过程可能发生在蛋白质催化氨基化之前的2',3'-二醇末端.
氨基酸混合无水化物的前生物可信合成支持了这种早期的RNA氨基酸酶化途径.

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