ABSTRACT
Elastin-mimetic protein polymers have been fabricated into elastic networks primarily via γ-radiation-induced, radical crosslinking of the material in the coacervate state. Synthesis of the elastin-mimetic protein gels is based on selective intermolecular reaction between the amino groups of the lysine residues and a bifunctional crosslinker. Both noncrosslinked proteins and protein networks display thermally responsive behavior typical of elastin analogues. Protein polymers based on Lys-25 were prepared by recombinant DNA technology and bacterial protein expression. The main advantage of this approach is the ability to directly produce high molecular weight polypeptides of exact amino acid sequence with high fidelity as required for this investigation. Protein biosynthesis affords an opportunity to completely specify the primary structure of the polypeptide repeat and analyze the effect of sequence and structural uniformity on the properties of the protein network. Expression of the concatameric gene under large-scale, batch fermentation conditions afforded an unoptimized yield of 64 mg purified polypeptide per liter of culture in LB medium.
