Related Experiment Video
Updated: Feb 7, 2026

Production and Visualization of Bacterial Spheroplasts and Protoplasts to Characterize Antimicrobial Peptide Localization
Published on: August 11, 2018
Visualization of diffusion limited antimicrobial peptide attack on supported lipid membranes
George R Heath1, Patrick L Harrison, Peter N Strong
1Department of Physics and Astronomy, Leeds University, Leeds, LS2 9JT, UK. k.miller@shu.ac.uk s.d.evans@leeds.ac.uk.
Abstract:
Understanding the mechanism of action of antimicrobial peptides (AMP) is fundamental to the development and design of peptide based antimicrobials. Utilizing fast-scan atomic force microscopy (AFM) we detail the attack of an AMP on both prototypical prokaryotic (DOPC:DOPG) and eukaryotic (DOPC:DOPE) model lipid membranes on the nanoscale and in real time. Previously shown to have a favourable therapeutic index, we study Smp43, an AMP with a helical-hinge-helical topology isolated from the venom of the North African scorpion Scorpio maurus palmatus. We observe the dynamic formation of highly branched defects being supported by 2D diffusion models and further experimental data from liposome leakage assays and quartz crystal microbalance-dissipation (QCM-D) analysis, we propose that Smp43 disrupts these membranes via a common mechanism, which we have termed 'diffusion limited disruption' that encompasses elements of both the carpet model and the expanding pore mechanism.
Related Concept Videos
Diffusion
Membrane Lipids
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
Protein Diffusion in the Membrane
Physiological Pharmacokinetic Models: Blood Flow-Limited Versus Diffusion-Limited Models
Acid Attack on Concrete
The rate at which hydrogen...
What are Lipids?

