Petal Shapes From A β–Peptide

A research team led by Hee-Seung Lee of the Korea Advanced Institute of Science & Technology has identified a β-peptide that self-assembles to form three-dimensional organic structures with unprecedented shapes (Angew. Chem. Int. Ed., DOI: 10.1002/anie.201003302). In the past, scientists have had difficulty controlling the size and shape of self-assembled organic structures. Various round shapes such as spheres, tubes, and rods have been obtained by peptide-based self-assembly, but other shapes have been elusive. Lee and coworkers now report that a β-peptide—a homooligomer of trans-(S,S)-2-aminocyclopentanecarboxylic acid—has unique conformational features that enable it to self-assemble in aqueous solution to form bars, stars, and flower petals. “The structures are beautiful,” says β-peptide self-assembly specialist Ferenc Fülöp of the University of Szeged, in Hungary. “The methodology may contribute to the construction of functional assemblies.” Lee believes the shapes could be useful as molecular machines for biomedical engineering, as joints or spacers for higher order molecular architectures, or as templates for formation of metallic inorganic materials.