Cd2+ coordination: an efficient structuring switch for polypeptide polymers†
Abstract
Stimuli-responsive polypeptides have practical applications in devices and therapeutic delivery. Here we report that coordination to Cd2+ metal species can be used as a robust stimulus to control both, α-helix and β-sheet secondary structuring of polypeptide polymers whose metal responsiveness was achieved in the presence of a competitive buffer. As evidenced by circular dichroism analyses, secondary structuring can be easily reversed using “sequestering” external ligands, such as EDTA, that are widely used in industry, to finally design a multivalent polypeptide backbone combining metal responsiveness to two other stimuli, pH and redox conditions.