title: Facile and precise formation of unsymmetric vesicles using the helix dipole, stereocomplex, and steric effects of peptides.
abstract: Unsymmetrical vesicular membranes were prepared from a binary mixture of the A3B-type and the AB-type host polypeptides, which were composed of the hydrophilic block (A) and the hydrophobic helical block (B) but with a different helix sense between the two host polypeptides. TEM and DLS revealed the formation of vesicles with ca. 100 nm diameter. The molecular assembly was driven by hydrophobic interaction, stereocomplex formation, and dipole-dipole interaction between hydrophobic helices. Furthermore, the A3B-type host polypeptide extended the hydrophilic block to the outer surface of vesicles as a result of the steric effect, resulting in the formation of unsymmetrical vesicular membranes. As a result, a functionalized AB-type guest polypeptide having the same helix sense with the A3B-type host polypeptide exposed the hydrophilic block to the outer surface. In contrast, an AB-type guest polypeptide having the same helix sense with the AB-type host polypeptide oriented the hydrophilic block to the inner surface. Functionalization of either the outer or inner surface of the binary vesicle is therefore facile to achieve when using either the right- or the left-handed helix of the functionalized guest polypeptide.
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University , Kyoto-Daigaku-Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Uesaka
authors.forename: Motoki
authors.initials: M
authors.lastname: Ueda
authors.forename: Tomoya
authors.initials: T
authors.lastname: Imai
authors.forename: Junji
authors.initials: J
authors.lastname: Sugiyama
authors.forename: Shunsaku
authors.initials: S
authors.lastname: Kimura
mesh_terms: D057927:Hydrophobic and Hydrophilic Interactions; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary
chemical_list: D010455:Peptides