title: Modular Design of Self-Assembling Peptide-Based Nanotubes.
abstract: An ability to design peptide-based nanotubes (PNTs) rationally with defined and mutable internal channels would advance understanding of peptide self-assembly, and present new biomaterials for nanotechnology and medicine. PNTs have been made from Fmoc dipeptides, cyclic peptides, and lock-washer helical bundles. Here we show that blunt-ended α-helical barrels, that is, preassembled bundles of α-helices with central channels, can be used as building blocks for PNTs. This approach is general and systematic, and uses a set of de novo helical bundles as standards. One of these bundles, a hexameric α-helical barrel, assembles into highly ordered PNTs, for which we have determined a structure by combining cryo-transmission electron microscopy, X-ray fiber diffraction, and model building. The structure reveals that the overall symmetry of the peptide module plays a critical role in ripening and ordering of the supramolecular assembly. PNTs based on pentameric, hexameric, and heptameric α-helical barrels sequester hydrophobic dye within their lumens.
authors.affiliation: School of Chemistry, University of Bristol , Cantock's Close, Bristol, BS8 1TS, United Kingdom.|Bristol Centre for Functional Nanomaterials, University of Bristol, Tyndall Avenue, Bristol, BS8 1FD, United Kingdom.
authors.forename: Natasha C
authors.initials: NC
authors.lastname: Burgess
authors.affiliation: Section Electron Microscopy, Department of Molecular Cell Biology, Leiden University Medical Center , Leiden, The Netherlands.
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Sharp
authors.affiliation: School of Chemistry, University of Bristol , Cantock's Close, Bristol, BS8 1TS, United Kingdom.
authors.forename: Franziska
authors.initials: F
authors.lastname: Thomas
authors.affiliation: School of Chemistry, University of Bristol , Cantock's Close, Bristol, BS8 1TS, United Kingdom.|School of Biochemistry, University of Bristol , Medical Sciences Building, University Walk, Bristol, BS8 1TD, United Kingdom.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Wood
authors.affiliation: School of Chemistry, University of Bristol , Cantock's Close, Bristol, BS8 1TS, United Kingdom.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Thomson
authors.affiliation: School of Biochemistry, University of Bristol , Medical Sciences Building, University Walk, Bristol, BS8 1TD, United Kingdom.
authors.forename: Nathan R
authors.initials: NR
authors.lastname: Zaccai
authors.affiliation: School of Biochemistry, University of Bristol , Medical Sciences Building, University Walk, Bristol, BS8 1TD, United Kingdom.
authors.forename: R Leo
authors.initials: RL
authors.lastname: Brady
authors.affiliation: School of Life Sciences, University of Sussex , Falmer, Brighton, East Sussex, BN1 9QG, United Kingdom.
authors.forename: Louise C
authors.initials: LC
authors.lastname: Serpell
authors.affiliation: School of Chemistry, University of Bristol , Cantock's Close, Bristol, BS8 1TS, United Kingdom.|School of Biochemistry, University of Bristol , Medical Sciences Building, University Walk, Bristol, BS8 1TD, United Kingdom.|BrisSynBio, University of Bristol , Life Sciences Building, Tyndall Avenue, Bristol, BS8 1TQ, United Kingdom.
authors.forename: Derek N
authors.initials: DN
authors.lastname: Woolfson
mesh_terms: D000595:Amino Acid Sequence; D008958:Models, Molecular; D008969:Molecular Sequence Data; D036103:Nanotechnology / Q000379:methods*; D045333:Nanotubes, Peptide / Q000737:chemistry*; D058105:Polymerization; D017433:Protein Structure, Secondary; D058767:Protein Unfolding; D013696:Temperature
chemical_list: D045333:Nanotubes, Peptide