The Development and Characterization of 'Rod-Hinge-Rod'-type Molecular Actuators

by Belasco, Laura

We have successfully synthesized a bivalent hinged molecule that binds metal to undergo large conformational changes, similar to an actuator. Spectrophotometric titrations as well as a Job plot have shown that binding occurs on a 1:1 ratio of metal to hinged molecule. Addition of EDTA as a metal scavenger causes the molecule to return to the unbound state. Gel filtration chromatography has shown the effects of metal binding on the overall size and shape of the actuator molecule; the "closed" form is much smaller than the "open" form, indicating that large conformational changes are occurring upon binding. Analytical ultracentrifugation has unambiguously confirmed that the molecules are binding metal in a monomeric fashion.