Microdiffraction of Spider Silk

This image shows the diffraction pattern of a single Nephila clavipes dragline silk fibre of about 5 micron diameter.^1,2

The crystalline fraction of the fibre, (less than 30 volume percent), corresponds to the b-poly(L-alanine) structure.³ Diffraction patterns like this can be recorded routinely using the ID13 microgoniometer. It has also been possible to record such patterns in-situ during silk extrusion from live spiders.^4,5

¹recorded at T=100K, l=0.0689 nm using a CCD detector
²Bram, A., C. Branden, et al. (1997) Journal of Applied Crystallography 30: 390-392.
³Fraser, R. D. B. and T. P. MacRae (1973) Conformations of Fibrous Proteins. New York, Academic Press (review)
⁴Riekel, C., M. Müller and F. Vollrath (1999) Macromolecules 32(13): 4464-4466.
⁵Riekel, C. and F. Vollrath (2001) Int. J. Biol. Macrom. 29(3): 203-210.