Conformational changes have been studied in silk fibers from the domestic silkworm Bombyx mori and a wild silkworm Samia cynthia ricini as a result of fractured by stretching. About 300 samples consisting of only the fractured regions of [1-13C]Ala or [1-13C]Gly labeled silk fibers were collected and observed by 13C CP/MAS NMR spectra. The total amount of these fractured fibers is only about 1 mg and therefore we used a home-built 1 mm microcoil MAS NMR probehead. A very small increase in the fraction of random coil was noted for the alanine regions of both silk fibroins and for the glycine region of B. mori silk fibroin. However, there is no difference in the spectra before and after fractured for the glycine region of S. c. ricini silk fibroin. Thus, the influence of fracture occurs exclusively at the Ala region for S. c. ricini. The relationship between sequence, fracture and structure is discussed. © 2010 Elsevier Inc. All rights reserved.
|Original language||English (US)|
|Number of pages||4|
|Journal||Solid State Nuclear Magnetic Resonance|
|State||Published - Jul 2010|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: The authors acknowledge the financial support of SENTAN, JST for the NMR probehead developments. TA acknowledges support from a Grant-in-Aid for Scientific Research from Ministry of Education, Science, Culture and Supports of Japan (18105007) and also the Bio-oriented Technology Research Advancement Institution (BRAIN), Japan. The authors acknowledge Prof. Mike Williamson, University of Sheffield, UK for many suggestions and careful reading of our paper.
ASJC Scopus subject areas
- Nuclear and High Energy Physics