title: Drawing-induced changes in morphology and mechanical properties of hornet silk gel films.
abstract: Complete amino acid sequences of the four major proteins (Vssilk 1-4) of silk (hornet silk) obtained from yellow hornet ( Vespa simillima , Vespinae, Vespidae) cocoons have been determined. The native structure of the hornet silk (HS), in which Vssilk 1-4 have an alpha-helix domain with coiled-coil alpha-helices and a beta-sheet domain, is restored when hornet silk gel films (HSGFs) are formed by pressing and drying HS hydrogel. Necking occurs when dry HSGFs are drawn; however, wet HSGFs can be uniaxially drawn with a draw ratio (DR) of 2. Drawing helps obtain high-performance films with a maximum tensile strength and tensile modulus of 170 MPa and 5.5 GPa, respectively. Drawing-induced changes in the orientation and conformation of the coiled-coil structure are investigated.
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, 305-8634, Japan. kamedat@affrc.go.jp
authors.forename: Tsunenori
authors.initials: T
authors.lastname: Kameda
authors.forename: Katsura
authors.initials: K
authors.lastname: Kojima
authors.forename: Eiji
authors.initials: E
authors.lastname: Togawa
authors.forename: Hideki
authors.initials: H
authors.lastname: Sezutsu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Teramoto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Tamada
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D018441:Biofilms; D005782:Gels; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D047011:Silk / Q000737:chemistry* / Q000648:ultrastructure*; D013718:Tensile Strength / Q000502:physiology*; D014863:Wasps / Q000502:physiology*; D014961:X-Ray Diffraction
chemical_list: D005782:Gels; D047011:Silk