Design of self-assembling peptide hydrogelators amenable to bacterial expression.

摘要: Hydrogels formed from self-assembling peptides are finding use in tissue engineering and drug delivery applications. Given the notorious difficulties associated with producing by recombinant expression, most typically prepared chemical synthesis. Herein, we report design of a family β-hairpin amenable to efficient production using an optimized bacterial expression system. Expressing peptides, EX1, EX2 EX3 contain identical eight-residue amphiphilic β-strands connected varying turn sequences that responsible for ensuring chain reversal proper intramolecular folding consequent self-assembly peptide into hydrogel network under physiological conditions. EX1 was initially used establish optimize system which all could be eventually individually expressed. Expression clones were designed allow exploration possible fusion partners investigate both enzymatic cleavage as means liberate target peptide. A systematic analysis systems followed fermentation optimization lead three expressed fusions BAD-BH3, BH3 domain proapoptotic BAD (Bcl-2 Associated Death) Protein. CNBr purification afforded 50, 31, 15 mg/L yields pure EX3, respectively. CD spectroscopy, TEM, rheological indicate these fold assembled well-defined fibrils constitute hydrogels having shear-thin/recovery properties.