title: Nanoscale Structural Features in Major Ampullate Spider Silk.
abstract: Spider major ampullate silk is often schematically represented as a two-phase material composed of crystalline nanodomains in an amorphous matrix. Here we are interested in revealing its more complex nanoscale organization by probing Argiope bruennichi dragline-type fibers using scanning X-ray nanodiffraction. This allows resolving transversal structural features such as an about 1 μm skin layer composed of around 100 nm diameter nanofibrils serving presumably as an elastic sheath. The core consists of a composite of several nm size crystalline nanodomains with poly(l-alanine) microstructure, embedded in a polypeptide network with short-range order. Stacks of nanodomains separated by less ordered nanosegments form nanofibrils with a periodic axial density modulation which is particularly sensitive to radiation damage. The precipitation of larger β-type nanocrystallites in the outer core-shell is attributed to MaSp1 protein molecules.
authors.affiliation: The European Synchrotron (ESRF) , CS40220, F-38043 Grenoble Cedex 9, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Riekel
authors.affiliation: The European Synchrotron (ESRF) , CS40220, F-38043 Grenoble Cedex 9, France.|Department of Analytical Chemistry, Ghent University , Krijgslaan 281, S12B-9000 Ghent, Belgium.
authors.forename: Manfred
authors.initials: M
authors.lastname: Burghammer
authors.affiliation: The European Synchrotron (ESRF) , CS40220, F-38043 Grenoble Cedex 9, France.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Dane
authors.affiliation: The European Synchrotron (ESRF) , CS40220, F-38043 Grenoble Cedex 9, France.
authors.forename: Claudio
authors.initials: C
authors.lastname: Ferrero
authors.affiliation: The European Synchrotron (ESRF) , CS40220, F-38043 Grenoble Cedex 9, France.
authors.forename: Martin
authors.initials: M
authors.lastname: Rosenthal
mesh_terms: D000409:Alanine / Q000737:chemistry*; D000818:Animals; D019476:Insect Proteins / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D047011:Silk / Q000737:chemistry*; D013112:Spiders
chemical_list: D019476:Insect Proteins; D047011:Silk; D000409:Alanine