(573d) Tuning the LCST-like Transition of Elastin-like-Peptide (ELP) and Conjugates of ELP to Collagen-like-Peptide (CLP) Using ELP Sequence and Composition

Peptide based biomaterials have garnered significant attention recently due to their ability to respond to external stimuli such as heat, light, and pH, thus allowing for controllable release of therapeutics for drug delivery applications and tunable mechanical and chemical properties for tissue engineering and in vitro cell culture applications. In this talk, we will present our recent work involving experiments, atomistic and coarse-grained molecular dynamics (MD) simulation studies of thermoresponsive polypeptides, specifically elastin-like peptides (ELP) and elastin-like peptide – collagen-like peptide (ELP-CLP) bioconjugates. ELPs are polypeptides that mimic the extracellular matrix protein, elastin, and are composed of repeat units of (VPGXG), where V, P, and G, are valine, proline, and glycine, respectively. The fourth residue, X, is termed the guest residue and can be any amino acid besides proline. Aqueous solutions of ELPs undergo a lower critical solution temperature (LCST)-like phase transition, which means ELPs are soluble below the transition temperature, T_t, and insoluble above T_t. In this talk we will show the impact of substitution of F with Tyrosine (Y) and Tryptophan (W) guest residues on the T_t of short ELPs when ELPs are conjugated to CLPs. We will also show the molecular interactions that drive the experimentally observed shifts in the transition and present some general design rules for future synthesis of thermoresponsive biomaterials.