Characterization of the nanoscale properties of individual amyloid fibrils

Jeffrey F. Smith, Tuomas P. J. Knowles, Christopher M. Dobson, Cait E. MacPhee, Mark E. Welland

Research output: Contribution to journalArticlepeer-review

Abstract

We report the detailed mechanical characterization of individual amyloid fibrils by atomic force microscopy and spectroscopy. These self-assembling materials, formed here from the protein insulin, were shown to have a strength of 0.6 +/- 0.4 GPa, comparable to that of steel (0.6-1.8 GPa), and a mechanical stiffness, as measured by Young's modulus, of 3.3 +/- 0.4 GPa, comparable to that of silk (1-10 GPa). The values of these parameters reveal that the fibrils possess properties that make these structures highly attractive for future technological applications. In addition, analysis of the solution-state growth kinetics indicated a breakage rate constant of 1.7 +/- 1.3 x 10(-8) s(-1), which reveals that a fibril 10 mu m in length breaks spontaneously on average every 47 min, suggesting that internal fracturing is likely to be of fundamental importance in the proliferation of amyloid fibrils and therefore for understanding the progression of their associated pathogenic disorders.

Original languageEnglish
Pages (from-to)15806-15811
Number of pages6
JournalProceedings of the National Academy of Sciences
Volume103
Issue number43
DOIs
Publication statusPublished - 24 Oct 2006

Keywords

  • atomic force microscopy
  • force spectroscopy
  • nanotechnology
  • prions
  • protein aggregation
  • BOVINE INSULIN
  • BETA-PROTEIN
  • MODEL
  • PEPTIDE
  • CONFORMATION
  • SPECTROSCOPY
  • NUCLEATION
  • MICROSCOPY
  • MECHANISM
  • FIBERS

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