How ions affect spider silk spinning

July 31, 2019

Contributing to technology development for tough artificial spider silk

RIKEN CSRS and RIKEN SPring-8 have identified how various ions affect spider silk proteins during the spinning process.

An understanding of what kind of ions contribute to silk protein structure during the spinning process has remained elusive. RIKEN researchers have successfully synthesized the repetitive sequence of amorphous and crystalline regions in silk protein (the main component of spider silk) using recombinant technologies and recreated spinning dope (the solution from which silk is spun) in vitro.

Analysis of the molecular structure of silk proteins in different ion environments then revealed that chaotropic ions such as sodium ions suppress intramolecular and intermolecular interactions in silk proteins to dissolve them, while kosmotropic ions such as phosphorus promote the formation of hydrogen bonds in glycine–rich regions and are essential to the formation of beta sheet structures.

These research results are expected to contribute to a series of studies for clarifying the spinning mechanisms for spider silk and to technological development for the manufacture of tough artificial spider silk fibers.


Original article
Chemical Communications doi:10.1039/C9CC03538A
N. A.a Oktaviani, A. Matsugami, F. Hayashi, K. Numata,
"Ion effects on the conformation and dynamics of repetitive domains of a spider silk protein: implications for solubility and β-sheet formation".

Keiji Numata
Team Leader
Biomacromolecules Research Team