Conformationally controlled oligocholate membrane transporters: learning through water play

Area of Science:

• Supramolecular Chemistry
• Chemical Biology
• Materials Science

Background:

• Controlled transport across lipid membranes is crucial for biological processes.
• Synthetic transporters are valuable tools for understanding biological systems and for applications like drug delivery and sensing.
• Cholic acid serves as a versatile building block for designing synthetic transporters.

Purpose of the Study:

• To present novel synthetic membrane transporters based on cholic acid.
• To demonstrate selective transport of molecules like glucose across lipid membranes.
• To explore the role of molecular conformation and water properties in transporter function.

Main Methods:

• Construction of "molecular baskets" from cholic acid for selective ion/molecule transport.
• Synthesis of oligocholate foldamers that form helical structures with internal binding pockets.
• Design of amphiphilic macrocycles that self-assemble into transmembrane nanopores.
• Investigation of molecular behavior in solution and its translation to membrane environments.

Main Results:

• "Molecular baskets" selectively shuttle glucose, excluding smaller ions like sodium.
• Oligocholate foldamers form helices capable of transporting polar guests.
• Amphiphilic macrocycles create nanopores in lipid bilayers driven by water interactions.
• Conformational control of transporters allows for tuning of their properties.

Conclusions:

• Cholic acid is a versatile scaffold for developing synthetic membrane transporters.
• Understanding molecular behavior in solution aids in designing effective membrane transport systems.
• Exploiting water's unique properties is key to successful supramolecular transport processes.