A monodisperse transmembrane α-helical peptide barrel

Area of Science:

• Biophysics
• Synthetic Biology
• Nanotechnology

Background:

• Fabricating monodisperse transmembrane barrels from synthetic peptides is challenging due to complex peptide-lipid interactions in hydrophobic membrane environments.
• Previous attempts have not successfully demonstrated the formation of such structures.

Purpose of the Study:

• To report the successful formation of a transmembrane pore via self-assembly of synthetic alpha-helical peptides.
• To characterize the structure and functionality of the engineered peptide pore.

Main Methods:

• Design and synthesis of 35 amino acid alpha-helical peptides based on the Wza D4 domain.
• Single-channel current recording to monitor pore formation and assembly intermediates.
• Functional assays to assess ion conductivity and blocker binding.

Main Results:

• Demonstrated the self-assembly of synthetic peptides into a transmembrane pore.
• Identified the pore as a helix barrel likely composed of eight parallel D4 peptides.
• Confirmed the pore's functionality in conducting ions and binding blockers.

Conclusions:

• Engineered alpha-helix barrels from synthetic peptides can form functional transmembrane pores.
• These peptide pores represent a novel platform for nanopore technologies.
• Potential applications include single-molecule sensing and nucleic-acid sequencing.