Priye Aashish, Yu Yuncheng, Hassan Yassin A, Ugaz Victor M
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843.
Department of Mechanical Engineering, Texas A&M University, College Station, TX 77843.
Proc Natl Acad Sci U S A. 2017 Feb 7;114(6):1275-1280. doi: 10.1073/pnas.1612924114. Epub 2017 Jan 24.
Porous mineral formations near subsea alkaline hydrothermal vents embed microenvironments that make them potential hot spots for prebiotic biochemistry. But, synthesis of long-chain macromolecules needed to support higher-order functions in living systems (e.g., polypeptides, proteins, and nucleic acids) cannot occur without enrichment of chemical precursors before initiating polymerization, and identifying a suitable mechanism has become a key unanswered question in the origin of life. Here, we apply simulations and in situ experiments to show how 3D chaotic thermal convection-flows that naturally permeate hydrothermal pore networks-supplies a robust mechanism for focused accumulation at discrete targeted surface sites. This interfacial enrichment is synchronized with bulk homogenization of chemical species, yielding two distinct processes that are seemingly opposed yet synergistically combine to accelerate surface reaction kinetics by several orders of magnitude. Our results suggest that chaotic thermal convection may play a previously unappreciated role in mediating surface-catalyzed synthesis in the prebiotic milieu.
海底碱性热液喷口附近的多孔矿物结构包含着微环境,使其成为益生元生物化学的潜在热点。但是,在启动聚合反应之前,如果没有化学前体的富集,就无法合成支持生命系统中高阶功能所需的长链大分子(例如多肽、蛋白质和核酸),而找到合适的机制已成为生命起源中一个关键的未解问题。在此,我们通过模拟和原位实验来展示,自然渗透热液孔隙网络的三维混沌热对流如何为离散目标表面位点的聚焦积累提供一个强大的机制。这种界面富集与化学物种的整体均匀化同步,产生了两个看似相反但协同结合的不同过程,从而将表面反应动力学加速了几个数量级。我们的结果表明,混沌热对流可能在介导益生元环境中的表面催化合成过程中发挥了之前未被认识到的作用。