Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Nat Chem. 2011 Aug 7;3(9):704-6. doi: 10.1038/nchem.1108.
The single-handedness of biological molecules is critical for molecular recognition and replication processes and would seem to be a prerequisite for the origin of life. A drawback of recently reported synthetic routes to RNA is the requirement for enantioenriched reactants, which fails to address the puzzle of how the single chirality of biological molecules arose. Here, we report the synthesis of highly enantioenriched RNA precursor molecules from racemic starting materials, with the molecular asymmetry derived solely from a small initial imbalance of the amino-acid enantiomers present in the reaction mixture. Acting as spectators to the main reaction chemistry, the amino acids orchestrate a sequence of physical and chemical amplification processes. The emergence of molecules of single chirality from complex, multi-component mixtures supports the robustness of this synthesis process under potential prebiotic conditions and provides a plausible explanation for the single-handedness of biological molecules before the emergence of self-replicating informational polymers.
生物分子的单一手性对于分子识别和复制过程至关重要，似乎是生命起源的前提。最近报道的 RNA 合成途径的一个缺点是需要对映体富集的反应物，这无法解决生物分子单一手性是如何产生的难题。在这里，我们报告了从外消旋起始原料合成高度对映体富集的 RNA 前体分子，分子不对称性仅源自反应混合物中存在的氨基酸对映体的微小初始不平衡。作为主要反应化学的旁观者，氨基酸协调了一系列物理和化学放大过程。单一手性分子从复杂的多组分混合物中出现，支持了这种合成过程在潜在的前生物条件下的稳健性，并为自我复制信息聚合物出现之前生物分子的单一手性提供了一个合理的解释。
