Phase separation and mechanical properties of an elastomeric biomaterial from spider wrapping silk and elastin block copolymers.
Elastin and silk spidroins are fibrous, structural proteins with elastomeric properties of extension and recoil. While elastin is highly extensible and has excellent recovery of elastic energy, silks are particularly strong and tough. This study describes the biophysical characterization of recombinant polypeptides designed by combining spider wrapping silk and elastin-like sequences as a strategy to rationally increase the strength of elastin-based materials while maintaining extensibility. We demonstrate a thermo-responsive phase separation and spontaneous colloid-like droplet formation from silk-elastin block copolymers, and from a 34 residue disordered region of Argiope trifasciata wrapping silk alone, and measure a comprehensive suite of tensile mechanical properties from cross-linked materials. Silk-elastin materials exhibited significantly increased strength, toughness, and stiffness compared to an elastin-only material, while retaining high failure strains and low energy loss upon recoil. These data demonstrate the mechanical tunability of protein polymer biomaterials through modular, chimeric recombination, and provide structural insights into mechanical design. © 2016 Wiley Periodicals, Inc. Biopolymers 105: 693-703, 2016.
Molecular Structure and Function Program, Research Institute, The Hospital for Sick Children, Toronto, Canada.
Lisa D
LD
Muiznieks
Molecular Structure and Function Program, Research Institute, The Hospital for Sick Children, Toronto, Canada.|Department of Biochemistry, University of Toronto, Canada.|Department of Pathology and Laboratory Medicine, University of Toronto, Canada.
Fred W
FW
Keeley
D000818:Animals; D004549:Elastin / Q000737:chemistry*; D020724:Elastomers / Q000737:chemistry*; D005349:Fibroins / Q000737:chemistry*; D013112:Spiders
D020724:Elastomers; D004549:Elastin; D005349:Fibroins
biomaterial design; elastin; protein elasticity; protein phase separation; spider wrapping silk