Generating Resilin inspired structures

Resilin is an elastomeric protein found in insect cuticles and is remarkable for its high strain, low stiffness, and high resilience. Since the first resilin sequence was identified in Drosophilia melanogaster (fruit fly), researchers have utilized molecular cloning techniques to construct resilin-based proteins for a number of different applications. Native resilin does not “stand-alone” but rather binds to the insect’s stiff chitin cuticle via carbohydrate binding modulus (CBM); in the form of chitin binding domain (ChBD) followed by its polymerization of di-tyrosine bridge crosslinks creating high-performance protein/polysaccharide composites. Inspired by the above material systems, a cellulose binding domain (CBD) was fused to the C-terminal of the res protein (res-CBD) in order to confer an intimate/specific interaction between resilin and the CNC.

The current work is aimed toward the production of bio-inspired structures using recombinant resilin and resilin-CBD (RES-CBD) expressed in E. coli:

• Production of crosslinked Resilin-CBD based hydrogels. Utilizing resilin natural crosslinking method and reported Tris(2,2′-bipyridyl) dichlororuthenium(II) hexahydrate ([Ru(bpy)₃]²⁺) mediated photo-crosslinking- a RES-Ru(bpy) solution was cast in to molds and exposed to direct sunlight to create an elastic gel. This photo-crosslinking reaction brings on the possibility to apply this gel as a 3D printable ink, for creation of Resilin inspired structures with the emphasis on creating nanoscale structures.

• Production of crosslinked Resilin-CBD/polyurethane (PU) foams. We expect to observe a synergistic effect of increased elastic modulus, shape recovery and resilience compared with CNC foams.