Conformational Transition of Regenerated Spider Silk in Water

Abstract:

Spider silks have excellent mechanical properties, which can even compare with some high-performance synthetic materials. Although as reported, the impressive mechanical properties are closely related to the primary amino acid sequence, the conformation that molecular chains form is also an important determinant. In this paper, effects of solvent, pH value, temperature, centrifugation and concentrating on the secondary structure of regenerated Ornithoctonus huwenna spider dragline silk protein aqueous solution were investigated by circular dichroism. Spidroin solutions prepared from different LiBr solutions had a distinct combination of secondary structures. The increasing temperature and concentrating can promote the formation of β-sheet structure. While centrifugation was opposite, which elevate the content of β-turn structure. Circular dichroic spectra quantitatively verified an increased α-helix structure content but a decrease of random coil and β-turn structure content with the increasing of pH value.

• Periodical: Advanced Materials Research (Volume 796)
• Pages: 107-111
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.796.107
• Online since: September 2013
• Authors: Ye Mei Zhang, Zhi Juan Pan
• Keywords: Circular Dichroism, Conformational Transition, pH, Regenerated Spider Silk

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