Hexagonally Ordered Arrays of α‑Helical Bundles Formed from Peptide-Dendron Hybrids

• Published in: Journal of the American Chemical Society 2017-11, Vol.139 (44), p.15977-15983
• Main Authors: Barkley, Deborah A, Rokhlenko, Yekaterina, Marine, Jeannette E, David, Rachelle, Sahoo, Dipankar, Watson, Matthew D, Koga, Tadanori, Osuji, Chinedum O, Rudick, Jonathan G
• Format: Article
• Language: English
• Subjects: Dendrimers - chemical synthesis; Dendrimers - chemistry; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Liquid Crystals - chemistry; MATERIALS SCIENCE; Models, Molecular; Nanostructures - chemistry; Peptides - chemical synthesis; Peptides - chemistry; Protein Conformation, alpha-Helical
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.7b09737

Combining monodisperse building blocks that have distinct folding properties serves as a modular strategy for controlling structural complexity in hierarchically organized materials. We combine an α-helical bundle-forming peptide with self-assembling dendrons to better control the arrangement of functional groups within cylindrical nanostructures. Site-specific grafting of dendrons to amino acid residues on the exterior of the α-helical bundle yields monodisperse macromolecules with programmable folding and self-assembly properties. The resulting hybrid biomaterials form thermotropic columnar hexagonal mesophases in which the peptides adopt an α-helical conformation. Bundling of the α-helical peptides accompanies self-assembly of the peptide-dendron hybrids into cylindrical nanostructures. The bundle stoichiometry in the mesophase agrees well with the size found in solution for α-helical bundles of peptides with a similar amino acid sequence.