The Institute of Plant Science and Genetics, The Hebrew University of Jerusalem, Rehovot
Nano- Bio Inspired composite materials that brings together the toughness of cellulose nano-fibers from the plant kingdom, the remarkable elasticity and resilience of resilin that enables flees to jump as high as 400 times their height from the insect kingdom, and the adhesion power of DOPA, the functional molecule of mussels that enable it to bind tightly under water to organic and inorganic matter from the marine kingdom.
Resilin is a polymeric rubber-like protein secreted by insects to specialized cuticle regions, in areas where high resilience and low stiffness are required. Resilin binds to the cuticle polysaccharide chitin via a chitin binding domain and is further polymerized through oxidation of the tyrosine residues resulting in the formation of dityrosine bridges and assembly of a high-performance protein-carbohydrate composite material. Plant cell walls also present durable composite structures made of cellulose, other polysaccharides, and structural proteins. Plant cell wall composite exhibit extraordinary strength exemplified by their ability to carry the huge mass of some forest trees. Inspired by the remarkable mechanical properties of insect cuticle and plant cell walls we have developed novel composite materials of resilin and Nano-Crystalline Cellulose (resilin-NCC) that display remarkable mechanical properties combining strength and elasticity. We produced a novel resilin protein with affinity to cellulose by genetically engineering a cellulose binding domain into the resilin. This CBD-Resilin enable, interfacing at the nano-level between the resilin; the elastic component of the composite, to the cellulose, the tough component. Furthermore, chemical and enzymatic modifications of the composite were developed to produce DOPA- Resilin-NCC which confers adhesive and sealant properties to the composite in the presence of water.
