title: Designed, Helical Protein Nanotubes with Variable Diameters from a Single Building Block.
abstract: Due to their structural and mechanical properties, 1D helical protein assemblies represent highly attractive design targets for biomolecular engineering and protein design. Here we present a designed, tetrameric protein building block, Zn8R4, which assembles via Zn coordination interactions into a series of crystalline, helical nanotubes whose widths can be controlled by solution conditions. X-ray crystallography and transmission electron microscopy (TEM) measurements indicate that all classes of protein nanotubes are constructed through the same 2D arrangement of Zn8R4 tetramers held together by Zn coordination. The mechanical properties of these nanotubes are correlated with their widths. All Zn8R4 nanotubes are found to be highly flexible despite possessing crystalline order, owing to their minimal interbuilding-block interactions mediated solely by metal coordination.
authors.affiliation: Department of Chemistry & Biochemistry, UCSD , 9500 Gilman Drive, La Jolla, California 92093, United States.
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Brodin
authors.affiliation: Department of Chemistry & Biochemistry, UCSD , 9500 Gilman Drive, La Jolla, California 92093, United States.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Smith
authors.affiliation: Department of Chemistry & Biochemistry, UCSD , 9500 Gilman Drive, La Jolla, California 92093, United States.
authors.forename: Jessica R
authors.initials: JR
authors.lastname: Carr
authors.affiliation: Department of Chemistry & Biochemistry, UCSD , 9500 Gilman Drive, La Jolla, California 92093, United States.
authors.forename: F Akif
authors.initials: FA
authors.lastname: Tezcan
mesh_terms: D008958:Models, Molecular; D036103:Nanotechnology / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry*; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry
chemical_list: D011506:Proteins; D015032:Zinc