Single-Molecule Force Spectroscopy on Curdlan: Unwinding Helical Structures and Random Coils

Curdlan is an important biomacromolecule whose bioactivity is strongly depending on its supramolecular structures. We have demonstrated that atomic force microscopy (AFM)-based single-molecule force spectroscopy (SMFS) is able to recognize triple- and double-helical structures and random coils in curdlan, which are controlled by the concentration of sodium hydroxide. We have obtained important information about the force-induced conformation transition and dynamics of supramolecular structures of curdlan at the molecular level.