Mechanosensitive Self-Replication Driven by Self-Organization

Abstract

At Sixes and Sevens: Molecular synthesis and macroscopic aggregation have often been regarded as entirely separate processes. From the researcher's standpoint, once reagents have been mixed, synthesis is largely passive, whereas processes such as crystallization can be more actively manipulated. Carnall et al. (p. 1502 ) characterized an unusual system in which the formation of aggregated cyclic macromolecules (macrocycles) from small peptide-based building blocks was governed by intimately interdependent factors ranging from the scale of covalent bond formation all the way to micron scale fiber growth. As the macrocycles stacked against one another to form the fibers, they remained loosely bonded enough internally to incorporate or expel individual building blocks. Varying the type of mechanical force applied to the growing fibers (either through shaking or stirring the solution), alternately favored formation of either 6-membered or 7-membered covalent macrocycles.