Assembly of transmembrane pores from mirror-image peptides

Area of Science:

• Biophysical Chemistry
• Nanobiotechnology
• Materials Science

Background:

• Transmembrane alpha-helical pores are crucial for nanobiotechnology applications.
• Designing pores with specific structural and functional properties is an ongoing challenge.
• Natural pores often use L-amino acids, limiting their stability and versatility.

Purpose of the Study:

• To engineer and characterize novel transmembrane pores using D-amino acid peptides.
• To investigate the self-assembly, selectivity, and sensing capabilities of D-amino acid pores.
• To compare the properties of D-amino acid pores with their L-amino acid counterparts.

Main Methods:

• Single-channel current recordings to assess pore formation and ion selectivity.
• Protease resistance assays to evaluate peptide stability.
• Fluorescence imaging of giant unilamellar vesicles (GUVs) to observe pore function in membranes.
• Molecular dynamics simulations to understand pore structure and dynamics.

Main Results:

• DpPorA peptides self-assemble into uniform, cation-selective transmembrane pores.
• D-amino acid pores exhibit enhanced protease resistance compared to L-amino acid analogs.
• DpPorA functions as a nanopore sensor for cyclic sugars, polypeptides, and polymers.
• Pores facilitate hydrophilic molecule transport in GUVs and show sequence-specific formation.

Conclusions:

• D-amino acid peptides can form stable, functional transmembrane pores with unique properties.
• DpPorA offers a versatile platform for nanopore sensing and molecular transport applications.
• This work advances the design principles for sophisticated biomimetic pores in nanobiotechnology.