Structural features and molecular aggregations of designed triple-stranded β-sheets in single crystals

Design, synthesis and single-crystal conformations of hybrid triple-stranded β-sheets composed of E-vinylogous residues are reported. Restricting conformational flexibility of β-strands through the insertion of carbon-carbon double bonds at facing positions leads to increased peptide crystallinity, which allowed unambiguous structural characterization of three-stranded β-sheets. This strategy can be further explored for the design of functional β-sheets.