Structural disorder in silk proteins reveals the emergence of elastomericity

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

Spider silks combine basic amino acids into strong and versatile fibers where the quality of the elastomer is attributed to the interaction of highly adapted protein motifs with a complex spinning process. The evaluation, however, of the interaction has remained elusive. Here, we present a novel analysis to study silk formation by examining the secondary structures of silk proteins in solution. Using the seven different silks of Nephila edulis as a benchmark system, we define a structural disorder parameter (the folding index, γ). We found that γ is highly correlated with the ratio of glycine present. Testing the correlation between glycine content and the folding index (γ) against a selected range of silks, we find quantitatively that, in order to achieve specialization with changes in mechanical performance, the spider's silks require higher structural flexibility at the expense of reduced stability and consequently an increased conversion-energy cost. Taken together, our biophysical and evolutionary findings reveal that silk elastomericity evolved in tandem with specializations in the process of silk spinning.

Detaljer

Författare
  • Cedric Dicko
  • David Porter
  • Jason Bond
  • John M. Kenney
  • Fritz Vollrath
Externa organisationer
  • University of Oxford
  • East Carolina University
Originalspråkengelska
Sidor (från-till)216-221
Antal sidor6
TidskriftBiomacromolecules
Volym9
Utgivningsnummer1
StatusPublished - 2008 jan 1
PublikationskategoriForskning
Peer review utfördJa
Externt publiceradJa