The prebiotic soup of a putative ‘RNA World’ would have been replete with a plethora of molecules resulting from complex chemical syntheses and exogeneous delivery. The presence of background molecules could lead to molecular crowding, potentially affecting the course of the reactions facilitated therein. Using NMR spectroscopy, we have analyzed the effect of crowding on the stacking ability of RNA monomers. Our findings corroborate that the purines stack more efficiently than the pyrimidine ribonucleotides. This competence is further enhanced in the presence of a crowding agent. This enhanced stacking could result in greater sequestration of the purine monomers, putting their ready availability for relevant nonenzymatic reactions into question. Thus, this study demonstrates the need for systematic characterization of molecular crowding in the context of prebiotically pertinent processes. Unraveling such phenomena is essential for our understanding of the transition from abiotic to biotic, during the origin of life.

假定的“RNA 世界”的益生元汤中可能充满了由复杂的化学合成和外源性递送产生的过多分子。背景分子的存在可能导致分子拥挤，可能影响其中促进的反应过程。我们使用核磁共振波谱分析了拥挤对 RNA 单体堆积能力的影响。我们的研究结果证实，嘌呤比嘧啶核糖核苷酸更有效地堆积。在存在拥挤代理的情况下，这种能力会得到进一步增强。这种增强的堆叠可能会导致嘌呤单体的更多螯合，从而使它们在相关非酶促反应中的可用性受到质疑。因此，这项研究证明了在生命起源前相关过程的背景下对分子拥挤进行系统表征的必要性。揭开这些现象对于我们理解生命起源期间从非生物到生物的转变至关重要。