Stimulus-Induced Relief of Intentionally Incorporated Frustration Drives Refolding of a Water-Soluble Biomimetic Foldamer

Frustrated, or nonoptimal, interactions have been proposed to be essential to a protein’s ability to display responsive behav-ior, such as allostery, conformational signaling, and signal transduction. However, the intentional incorporation of frustrated noncovalent interactions has not been explored as a design element in the field of dynamic foldamers. Here we report the design, synthesis, characterization, and MD simulations of the first dynamic water-soluble foldamer that, in response to a stimulus, exploits relief of frustration in its noncovalent network to structurally rearrange from a pleated to intercalated co-lumnar structure. Thus, relief of frustration provides the energetic driving force for structural rearrangement. This work repre-sents a previously unexplored design element for development of stimulus-responsive systems that has potential application to materials chemistry, synthetic biology, and molecular machines.