title: Fusion and fission of molecular assemblies of amphiphilic polypeptides generating small vesicles from nanotubes.
abstract: Three amphiphilic block polypeptides, (sarcosine)m-b-(l- or d-Leu-Aib)n(L16, D16, D14), having different helical chain lengths or helicity are synthesized. A mixture of L16, D16, and D14 generates vesicles of diameters more than ca. 130 nm by injecting the ethanol solution into water and heating at 90°C for 1 h. On the other hand, when nanotubes composed of L16 and D14 having ca. 50 nm diameter are mixed with nanosheets composed of D16, smaller and homogeneous vesicles of ca. 60 nm diameter are obtained with the heat treatment. The time lapse TEM image analysis of the mixtures revealed some transient structures of nanotubes sticking a nanosheet or a vesicle at the open end of nanotubes. The precise size control of vesicles is therefore attainable by using nanotubes as a structural template regulating the size of vesicles near to the nanotube diameter upon the membrane fission processes.
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto-Daigaku-Katsura, Nishikyo-Ku, Kyoto, 615-8510, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Watabe
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto-Daigaku-Katsura, Nishikyo-Ku, Kyoto, 615-8510, Japan.
authors.forename: Cheol
authors.initials: C
authors.lastname: Joo Kim
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto-Daigaku-Katsura, Nishikyo-Ku, Kyoto, 615-8510, Japan.
authors.forename: Shunsaku
authors.initials: S
authors.lastname: Kimura
mesh_terms: D057927:Hydrophobic and Hydrophilic Interactions; D008027:Light; D046529:Microscopy, Electron, Transmission; D008958:Models, Molecular; D015394:Molecular Structure; D045333:Nanotubes, Peptide / Q000737:chemistry* / Q000648:ultrastructure*; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D012521:Sarcosine / Q000737:chemistry*; D012542:Scattering, Radiation; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D045333:Nanotubes, Peptide; D010455:Peptides; D012521:Sarcosine
keywords: amphiphilic peptides; membrane fission; membrane fusion; nanotubes; vesicles