Light-Driven Molecular Motors Boost the Selective Transport of Alkali Metal Ions through Phospholipid Bilayers

Abstract

A hydrophobic light-driven rotary motor is functionalized with two 18-crown-6 macrocycles and incorporated into phospholipid bilayers. In the presence of this molecular construct, fluorescence assays and patch clamp experiments show the formation of selective alkali ion channels through the membrane. Further, they reveal a strongly accelerated ion transport mechanism under light irradiation. This increase of the fractional ion transport activity (up to 400%) is attributed to the out-of-equilibrium actuation dynamics of the light-driven rotary motors that helps overcoming the activation energy necessary to achieve translocation of alkali ions between macrocycles along the artificial channels.

Photomodulation of Transmembrane Transport and Potential by Stiff-Stilbene Based Bis(thio)ureas

“…In most cases, however, a more detailed investigation into the mechanism of transport is still to follow. The use of light to control substrate binding and transport has the clear advantage that it can be applied with high spatiotemporal precision and that no chemical waste is generated in the system . In particular, photocontrol of chloride-selective transport would be a highly interesting and promising achievement in the context of developing physiological tools to study diseases associated with defective transport as well as optopharmacological tools to stimulate neuronal activity.…”

A Light‐Driven Molecular Machine Controls K+ Channel Transport and Induces Cancer Cell Apoptosis

“…Coincidentally, very recently, the Barboiu and Giuseppone groups reported the use of a light‐driven molecular motor to increase ion transport [19] . These authors demonstrated that the fractional ion transport activity increased due to the out‐of‐equilibrium actuation dynamics of light‐driven rotary motion.…”

Light‐Controlled Ionic/Molecular Transport through Solid‐State Nanopores and Nanochannels

“…For example, Xiang et al created a frequency responsive photoelectric device by anchoring the BR multilayers on the solidstate porous alumina nanochannel array, [5] realizing the conversion of flickering light flashes with different frequencies into distinguishable patterns of photocurrent. Furthermore, inspired by the marvelous structure and functions of biological ion channels and ion pumps, artificial biomimetic ion transport systems, including liquid or lipid membranes [6][7][8][9][10] and solid-state nanochannels, [11][12][13][14][15] have been developed for basic studies [16][17][18][19] and practical applications. [20][21][22] These researches strongly deepen our understanding of neuron signal transduction and biological processes.…”