Beta transition and stress-induced phase separation in the spinning of spider dragline silk

Queen Mary, University of London, Londinium, England, United Kingdom
International Journal of Biological Macromolecules (Impact Factor: 3.1). 07/2000; 27(3):205-10. DOI: 10.1016/S0141-8130(00)00124-0
Source: PubMed

ABSTRACT Spider dragline silk is formed as the result of a remarkable transformation in which an aqueous dope solution is rapidly converted into an insoluble protein filament with outstanding mechanical properties. Microscopy on the spinning duct in Nephila edulis spiders suggests that this transformation involves a stress-induced formation of anti-parallel beta-sheets induced by extensional flow. Measurements of draw stress at different draw rates during silking confirm that a stress-induced phase transition occurs.

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