Exploiting Materials Binding Peptides for the Organization of Resilient Biomolecular Constructs.

Abstract

Elastomers based on the resilin protein confer exceptional mechanical resilience in nature, but it remains elusive to recover the remarkable properties of these materials when they are made in the laboratory. This is possibly due to preorganized conformations of resilin in its natural setting, facilitating Tyr-based cross-linking. Here, resilin-like peptides (RLPs) are conjugated with a graphene-binding peptide, P1, to produce P1/RLP conjugates, in which the P1 domain may provide favorable preorganization on a graphene surface. Experiments using quartz crystal microbalance analysis and atomic force microscopy identified that the parent RLPs demonstrate negligible graphene binding; however, integration of the P1 with the RLPs resulted in the formation of dense, patterned bioligand overlayers on graphene. To complement this, molecular simulations revealed a notable difference in binding mode of the conjugates compared with typical materials binding peptides. Specifically, the adsorption of the P1/RLP conjugates did not focus on a few strongly bound "anchor" residues, but instead supported a more diffuse mode of binding, with many more participating residues featuring moderate contact. Analysis of the number of available Tyr residues (i.e., those not adsorbed at the surface) indicate that the RLP2-based conjugates will provide greater opportunity for cross-linking when adsorbed on graphene, providing a framework to generate patterned elastomeric materials.