Related Experiment Video
Updated: Oct 2, 2026

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides
Published on: November 21, 2013
Supramolecular Assembly of an Antimicrobial Peptide Into a Pore
Kathyana Deeyagahage1, Poonam Dhindwal1, Michal T Boniecki2
1Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Abstract:
Antimicrobial peptides (AMPs) have long been ascribed the ability to form pores. These structures, some observed, others inferred, vary in their mechanisms of action, though most are associated with lysis. Here, we show that an AMP derived from a truncated staphylococcal δ-toxin can form functional pores that do not cause rapid lysis but, instead, we suggest that they act as self-transport systems. Specifically, a 17-amino acid AMP named STIP3-1 was observed to oligomerize and form a unique supramolecular helical assembly with an ∼14 Å pore. Substitutions to the STIP3-1 peptide abolished our ability to detect pore formation in model membranes and prevented peptide accumulation in Staphylococcus aureus. In the case of G3A and G3Aib variants, the substitutions resulted in stabilization of antiparallel 4-helix bundles rather than a nanotubular assembly characterized by a two-ring structure formed by repeating trimers. MD simulations suggest that Gly may impart versatility in STIP3-1 phospholipid binding. Our observation of this remarkable STIP3-1 structure expands how we can approach mechanistic and translational studies of AMPs.
Related Concept Videos
Structure of Porins
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Protein Folding
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Inhibitors of Gram-positive Cell Wall Synthesis
Porin Insertion in the Outer Mitochondrial Membrane
Three models describe the assembly of porins by the SAM complex and their insertion into the outer membrane. Model 1 suggests that porins are assembled outside the SAM channel as the...
Peptide Bonds

