Bioinspired helical systems with defined chirality assembled from discrete peptide and glycan amphiphiles

Abstract

Molecular helices are ubiquitous in biological systems and play key roles in life functions such as recognition, coding and transferring information, replication, catalytic activity, among others. They can have different handedness and dimensions from molecular to macroscale but the exact mechanisms for their formation are still elusive. In vivo, they are formed from homochiral building blocks (L-amino acids and D-carbohydrates) by complex, orchestrated supramolecular aggregation processes. Thus, self-assembly of synthetic chiral analogues of these blocks has been explored to understand the underlying principles of supramolecular chirality, their importance in (supra)molecular biorecognition in the physiological environment, as well as to develop novel functional biomaterials. In this review, we discuss the role of different factors in the formation of supramolecular helices and the definition of handedness in model systems composed by peptides and carbohydrates: the effect(s) of the chirality and sequence in the building blocks, (non)chiral additives, assembly conditions, i.e. co-solvent, pH, temperature are showcased. The possibility to tune these factors towards assembly of helices with defined chirality is also discussed and supported by recent examples from the literature. Finally, we explore the importance of these assemblies in different bioapplications.