Genetic Fusion of Intrinsically Disordered Polypeptides Affords Thermoresponsiveness to Coiled Coil Bundlemers

Researcher(s)

  • Victoria Thompson, Chemical Engineering, University of Florida

Faculty Mentor(s)

  • Kristi Kiick, Materials Science and Engineering, University of Delaware

Abstract

Resilin and elastin are elastomeric proteins that both exhibit stimuli responsive behaviors. Resilin is derived from insects and elastin from mammalian connective tissues. Both resilin and elastin are intrinsically disordered proteins (IDPs), meaning they have no regular secondary structure. These IDPs can be genetically fused with a coiled-coiled peptide, which allows the unit to be responsive to stimuli such as pH, temperature, and chemical environment. There were two main goals of this project. First, the phase transition behavior of resilin-like polypeptides (RLPs) and elastin-like polypeptides (ELPs) were compared. And second, the effect that substituting different central amino acids in the resilin portion of the RLPs has on the yield, purity, composition, and phase transition temperature of these polypeptides was documented. To yield the desired protein sequence, recombinant synthesis in E. coli was utilized and purification under denaturing conditions was applied. Then the newly synthesized protein was analyzed using Gel Electrophoresis and UPLC-ESIMS to characterize the molecular weight and purity of the produced protein. Next, UV-Vis Turbidimetry was used to analyze the phase separation behavior of the polypeptide in response to temperature change. Results showed that all sequences demonstrated a phase transition, indicating that the sequences are responsive to temperature.