Dissipative Self-Assembly of Peptides

In molecular self-assembly, molecules interact with each other by non-covalent interactions to form larger structures. The process occurs in-equilibrium, which means that molecules can leave the assembly and reassemble elsewhere, but that occurs on average with equal rates. For self-assembly, peptides have proven to be a particularly useful building block, in part because of their versatility. Biology also uses self-assembly to create functional materials. For example, components of the cytoskeleton, like actin filament and microtubules, are self-assembled proteins. In other words, biology uses the same building blocks and design rules as supramolecular chemists to create functional structures. However, biological assemblies are vastly more complex than their synthetic counterparts. The discrepancy is in part because proteins are more complex than the peptides we use as building blocks. Another contributing factor to the difference in complexity is that most assemblies in living systems exist out of equilibrium. To use peptides for complex functions as biology does, we should understand and be able to create peptide assemblies out of equilibrium. In this work, we review recent advances towards the creation of peptide assemblies that exist out of equilibrium driven by an external energy source.