Molecular Orientation and Two-Component Nature of the Crystalline Fraction of Spider Dragline Silk

  title={Molecular Orientation and Two-Component Nature of the Crystalline Fraction of Spider Dragline Silk},
  author={Alexandra H. Simmons and Carl A. Michal and Lynn W. Jelinski},
  pages={84 - 87}
The molecular origin of the exceptional mechanical properties of spider silk is unclear. This paper presents solid-state 2H nuclear magnetic resonance data from unoriented, oriented, and supercontracted fibers, indicating that the crystalline fraction of dragline silk consists of two types of alanine-rich regions, one that is highly oriented and one that is poorly oriented and less densely packed. A new model for the molecular-level structure of individual silk molecules and their arrangement… 
Molecular chain orientation in supercontracted and re-extended spider silk.
  • D. Grubb, G. Ji
  • Materials Science
    International journal of biological macromolecules
  • 1999
The molecular structure of spider dragline silk: Folding and orientation of the protein backbone
Two-dimensional solid-state NMR data indicate that all domains in dragline silk have a preferred secondary structure and are strongly oriented, with the chains predominantly parallel to the fiber.
Atomistic model of the spider silk nanostructure
Spider silk is an ultrastrong and extensible self-assembling biopolymer that outperforms the mechanical characteristics of many synthetic materials including steel. Here we report atomic-level
Structure of Silk using Solid‐State NMR
Silks are natural protein fibers produced by insects and spiders. The mechanical properties of silks span a wide range, and include combinations, for example, strength and extensibility, that are
Combined structural model of spider dragline silk
In this study we attempt to determine the interconnection of the nanocrystal and amorphous phases in two states of spider dragline silk, native, and supercontracted with water. Infrared spectroscopy
Composition and Hierarchical Organisation of a Spider Silk
The morphological defined structural elements in dragline silk of Nephila clavipes are linked to their biochemical composition and physicochemical properties to understand the composite nature of silk and its supra-molecular organisation.


Molecular modeling of spider silk elasticity
We introduce the first comprehensive molecular model of spider dragline elasticity which clearly integrates most of the information known to date about the structure of the fiber. In accordance with
Molecular mechanism of spider silk elasticity.
Structure of a protein superfiber: spider dragline silk.
  • M. Xu, R. Lewis
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1990
A model for the physical properties of fiber formation, strength, and elasticity, based on this repetitive protein sequence of spider major ampullate (dragline) silk, is presented.
A Physico-Chemical Study of the Supercontraction of Spider Major Ampullate Silk Fibers
The suggestion is that water ruptures hydrogen bonds between amino and carboxy groups, in the anti-parallel rippled sheet model of silk, to produce radial swelling and allow SC.
Physical and chemical microstructure of spider dragline: A study by analytical transmission electron microscopy
We report the first direct observations of the physical and chemical microstructure of spider dragline, revealed by analytical transmission electron microscopy. Individual crystallites were imaged
Solid-State 13C NMR of Nephila clavipes Dragline Silk Establishes Structure and Identity of Crystalline Regions
13 C CP/MAS NMR spectra of dragline silk of Nephila clavipes show unambiguously that the alanine residues are present in the β-sheet conformation. Proton T 1ρ data show that the heterogeneities in
Microscopic Dynamics and Macroscopic Mechanical Deformation of Poly(p-phenyleneterephthalamide) Fibers
Deuterium NMR methods are used to characterize the dynamic structure of PPTA [poly(p-phenyleneterephthalamide)] fiber as a function of tension. Spin-lattice relaxation results indicate that the