Outer surface modification of synthetic multifunctional pores.

Area of Science:

• Supramolecular chemistry
• Membrane biophysics
• Materials science

Background:

• Beta-barrels are key self-assembling structures for creating transmembrane pores.
• Modifying outer surfaces can alter pore characteristics and stability.
• Understanding these modifications is crucial for designing novel nanomaterials.

Purpose of the Study:

• To investigate the impact of LWV triads on p-octiphenyl beta-barrel pores.
• To compare these modified pores with conventional rigid-rod beta-barrels.
• To elucidate the relationship between pore stability, monomer concentration, and beta-propensity.

Main Methods:

• Synthesis and characterization of p-octiphenyl beta-barrels with LWV triads.
• Fluorescence depth quenching to determine transmembrane orientation.
• Single-channel lifetime measurements to assess pore stability.
• Analysis of pore activity dependence on monomer concentration.

Main Results:

• LWV triads maintained tetrameric pore multifunctionality, including ion selectivity inversion and molecular recognition.
• Increased pore activity was observed, linked to high bilayer affinity of W over V.
• Transmembrane orientation confirmed barrel-stave pore formation.
• LWV triads destabilized pores in membranes and solution, indicating lower beta-propensity of W compared to V.

Conclusions:

• External LWV triads on beta-barrels preserve pore interior integrity and function.
• The observed pore destabilization suggests W monomers possess lower beta-propensity than V.
• Pore stability is influenced by monomer concentration and intrinsic beta-propensity, with implications for supramolecular assembly.