Self-assembly of small-molecule fumaramides allows transmembrane chloride channel formation

Abstract

This study reports the formation of self-assembled transmembrane anion channels by small-molecule fumaramides. Such artificial ion channel formation was confirmed by ion transport across liposomes and by planar bilayer conductance measurements. The geometry-optimized model of the channel and Cl ion selectivity within the channel lumen was also illustrated.

A Glutathione Activatable Ion Channel Induces Apoptosis in Cancer Cells by Depleting Intracellular Glutathione Levels

“…Ion transport activity : Ion transport activities of compounds 1 a – 1 c , 2 , and 3 were evaluated across large unilamellar vesicles consisting of egg yolk phosphatidylcholine (EYPC‐LUVs⊃HPTS) by 8‐hydroxypyrene‐1,3,6‐trisulfonate (HPTS) based fluorometric methods . The EYPC vesicles, entrapping the pH‐sensitive HPTS dye (p K a =7.2), were prepared with internal and external pH 7.0, and a pH gradient was then applied by addition of NaOH (i.e., ΔpH=0.8) in the extravesicular buffer . The collapse of the pH gradient upon the addition of 1 a – 1 c , 2 and 3 was monitored by the change in the dye fluorescence intensity at λ em =510 nm ( λ ex =450 nm) (see Supporting Information (SI) for details).…”

Apoptosis-inducing activity of a fluorescent barrel-rosette M+/Cl− channel

“…The ion transport activity of 2-hydroxy-N 1 ,N 3 -diarylisophthalamide derivatives 1a-1d was checked by different uorometric methods across egg yolk phosphatidylcholine unilamellar vesicles (EYPC-LUVs). [41][42][43][44][45] At rst, large EYPC-LUVs, entrapping the pH-sensitive dye 8-hydroxypyrene-1,3,6-trisulfonate (HPTS, pK a ¼ 7.2), were prepared, and NaOH was added in the extravesicular buffer to create a pH gradient (i.e., DpH ¼ 0.8). The rate of change in the uorescence intensity was monitored aer the addition of 1a-1d, separately, and nally, Triton X-100 was added to lyse the vesicles for the complete leakage of the HPTS dye.…”

Self-assembly as a key player for materials nanoarchitectonics

“…Nanoarchitectonics upon self-assembly process to promote biomimetic and bio-inspired functions is also attractive research target [146,147]. For example, Talukdar and co-workers reported formation of transmembrane chloride channel through self-assembly of small-molecule fumaramides ( Figure 5) [148]. Fumaramides and the corresponding maleamides with various N-terminal hydrophobic groups were synthesized and self-assembled into transmembrane channel structures within lipid bilayer membranes.…”