Elucidating the physicochemical processes of light-activated rotary motors embedded in lipid membranes

Abstract

The integration of light-driven molecular machines with lipid membranes holds significant interest for advancing biological applications, necessitating a comprehensive understanding of the underlying biophysical mechanisms. Here, we report the incorporation of nine alkene-based molecular rotary motors with diverse chemical compositions into synthetic lipid membranes and establish a set of experimental tools to probe their behavior. Through molecular-scale characterizations, including motor positioning, orientation, aggregation, and uptake efficiency, as well as analysis of rotation cycle dynamics under membrane confinement, we elucidate the complex interactions between these molecular machines and lipid membranes. Moreover, we investigate the influence of motor incorporation on the biophysical properties of the membrane, such as fluidity and membrane tension. Additionally, we examine light-triggered membrane deformations and area expansion using the electrodeformation of giant vesicles. Our findings reveal significant differences in how molecular rotary motors interact with membranes, providing a comprehensive framework for future applications of synthetic molecular machines in biological contexts.