The Silk I and Lamella Structures of (Ala-Gly)15 as the Model of Bombyx mori Silk Fibroin Studied with Solid State NMR

  • Tetsuo AsakuraEmail author
  • Yu Suzuki
  • Yasumoto Nakazawa
Part of the Biologically-Inspired Systems book series (BISY, volume 5)


The specific structures, Silk I and Lamella, observed in the sequence model peptides, (Ala-Gly)n of Bombyx mori silk fibroin, could be determined by several 13C solid state NMR techniques coupled with 13C selective labeling of the peptides. The former is the silk fibroin structure before spinning that is a key structure in order to clarify the mechanism of formation of the silk fiber with exceptional strength and toughness from the aqueous solution in silkworm. The latter is a unique structure related with Silk II as referred to the silk fibroin structure after spinning and useful in molecular design the biomaterials with silk. The 13C solid state NMR coupled with 13C/15N stable isotope labeling is very useful to clarify these specific structures appeared in the fibrous protein and therefore the process of the determination is described in detail.


Silk fibroin Bombyx mori Solid state NMR Stable isotope labelling 



T. A. acknowledges the financial support from Grant from the Ministry of Agriculture, Forestry and Fisheries of Japan (Agri-Health Translational Research Project) and Grant-in-Aid for Scientific Research from Ministry of Education, Science, Culture and Supports of Japan (23245045), (21550112) and (23500512).


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© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Department of BiotechnologyTokyo University of Agriculture and TechnologyTokyoJapan
  2. 2.Institute for Molecular ScienceOkazakiJapan

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