Aldana Maximino, Fuentes-Cabrera Miguel, Zumaya Martín
Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Colonia Chamilpa, Cuernavaca 62210, Morelos, Mexico.
Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Coyoacán 04510, Mexico City, Mexico.
Entropy (Basel). 2020 Feb 22;22(2):251. doi: 10.3390/e22020251.
Self-assembly is a spontaneous process through which macroscopic structures are formed from basic microscopic constituents (e.g., molecules or colloids). By contrast, the formation of large biological molecules inside the cell (such as proteins or nucleic acids) is a process more akin to self-organization than to self-assembly, as it requires a constant supply of external energy. Recent studies have tried to merge self-assembly with self-organization by analyzing the assembly of self-propelled (or active) colloid-like particles whose motion is driven by a permanent source of energy. Here we present evidence that points to the fact that self-propulsion considerably enhances the assembly of polymers: self-propelled molecules are found to assemble faster into polymer-like structures than non self-propelled ones. The average polymer length increases towards a maximum as the self-propulsion force increases. Beyond this maximum, the average polymer length decreases due to the competition between bonding energy and disruptive forces that result from collisions. The assembly of active molecules might have promoted the formation of large pre-biotic polymers that could be the precursors of the informational polymers we observe nowadays.
自组装是一个自发过程，通过该过程由基本微观成分（如分子或胶体）形成宏观结构。相比之下，细胞内大生物分子（如蛋白质或核酸）的形成过程更类似于自组织而非自组装，因为它需要持续供应外部能量。最近的研究试图通过分析由永久能量源驱动运动的自推进（或活性）类胶体粒子的组装，将自组装与自组织结合起来。在此我们提供的证据表明，自推进显著增强了聚合物的组装：发现自推进分子比非自推进分子更快地组装成类聚合物结构。随着自推进力增加，平均聚合物长度朝着最大值增加。超过这个最大值后，由于键合能与碰撞产生的破坏力之间的竞争，平均聚合物长度会减小。活性分子的组装可能促进了大型前生物聚合物的形成，这些聚合物可能是我们如今观察到的信息聚合物的前体。
