Thermal characteristics and cadmium binding behavior of EC-ELP fusion polypeptides

•The cadmium binding affinity of EC-ELP fusion protein was examined by comparing the turbidity profiles to three other heavy metal ions.•The amount of Cd2+ adsorbed to the EC–ELP fusion proteins and the resulting Tt changes were explored according to the number of EC repeating units.•We observed whether our EC–ELP fusion proteins could be reused, after removing the adsorbed cadmium ions. Elastin-like polypeptides (ELPs) are stimulus–responsive protein-based biopolymers that exhibit phase transition behavior. By joining them to synthetic phytochelatin (EC), EC–ELP fusion proteins with temperature sensitivity and metal-binding functionality were generated to remove heavy metal ions biologically. Three different EC domains (EC10, EC20, EC30) were incorporated into the ELP, and the EC–ELP fusion proteins were expressed in E. coli. Their thermal properties and metal binding abilities were then investigated according to the EC length. In addition, the feasibility of reusing EC–ELPs and the cadmium ion binding affinity of reused EC–ELPs were explored.