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

@article{Simmons1996MolecularOA,
  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},
  journal={Science},
  year={1996},
  volume={271},
  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… 
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