Elastic-contractile protein material

Figure 9.5. Elastic-contractile protein material, (GVGVPlai, obtained by phase separation from the ruptured E. coli cells of a single fermentation run. (A) Note taffy-like appearance of the mass of product. (B) Viscoelastic mass being pulled into a fine strand. (Courtesy of Bioelastics Research, Ltd.)...

Due to the struggle to survive under circumstances of limited food supply, organisms evolve to use the most efficient mechanism available to their composition. The most efficient mechanism available to the proteins that sustain Life would seem to be the apolar-polar repulsive free energy of hydration as observed for the inverse temperature transitions for hydrophobic association. The efficiency of designed elastic-contractile protein-based machines and a number of additional properties make designed protein-based materials of substantial promise for the marketplace of the future. 

The molecular basis of contractility is now quite well understood. It is generally assumed that elastic proteins and rubber-like materials are built of flexible polypeptide chains. The similarity in the molecular mechanism of such materials is indicated by the fact that all yield S-shaped curves. Such curves are obtained for gelatin and glue, and by Treitel (95) for cellulose in the living plant. 

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