Phospholipid dependent mechanism of smp24, an α-helical antimicrobial peptide from scorpion venom

Harrison, Patrick L.; Heath, George R.; Johnson, Benjamin R.G.; Abdel-Rahman, Mohamed A.; Strong, Peter N.; Evans, Stephen D.; Miller, Keith

Abstract

Determining the mechanism of action of antimicrobial peptides (AMPs) is critical if they are to be developed into the clinical setting. In recent years high resolution techniques such as atomic force microscopy (AFM) have increasingly been utilised to determine AMP mechanism of action on planar lipid bilayers and live bacteria. Here we present the biophysical characterisation of a prototypical AMP from the venom of the North African scorpion Scorpio maurus palmatus termed Smp24. Smp24 is an amphipathic helical peptide containing 24 residues with a charge of + 3 and exhibits both antimicrobial and cytotoxic activity and we aim to elucidate the mechanism of action of this peptide on both membrane systems.

Using AFM, quartz crystal microbalance-dissipation (QCM-D) and liposomal leakage assays the effect of Smp24 on prototypical synthetic prokaryotic (DOPG:DOPC) and eukaryotic (DOPE:DOPC) membranes has been determined. Our data points to a toroidal pore mechanism against the prokaryotic like membrane whilst the formation of hexagonal phase non-lamellar phase structures is seen in eukaryotic like membrane. Also, phase segregation is observed against the eukaryotic membrane and this study provides direct evidence of the same peptide having multiple mechanisms of action depending on the membrane lipid composition.

Citation

Harrison, P. L., Heath, G. R., Johnson, B. R., Abdel-Rahman, M. A., Strong, P. N., Evans, S. D., & Miller, K. (2016). Phospholipid dependent mechanism of smp24, an α-helical antimicrobial peptide from scorpion venom. BBA - Biomembranes, 1858(11), 2737-2744. https://doi.org/10.1016/j.bbamem.2016.07.018

• Journal Article Type: Article
• Acceptance Date: Jul 27, 2016
• Online Publication Date: Jul 30, 2016
• Publication Date: 2016-11
• Deposit Date: May 7, 2019
• Publicly Available Date: May 8, 2019
• Journal: Biochimica et Biophysica Acta - Biomembranes
• Print ISSN: 0005-2736
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 1858
• Issue: 11
• Pages: 2737-2744
• DOI: https://doi.org/10.1016/j.bbamem.2016.07.018
• Keywords: Antimicrobial peptides; Membrane damage; Atomic force microscopy; Quartz crystal microbalance-dissipation
• Public URL: https://hull-repository.worktribe.com/output/1738627
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0005273616302711
• Additional Information: This article is maintained by: Elsevier; Article Title: Phospholipid dependent mechanism of smp24, an α-helical antimicrobial peptide from scorpion venom; Journal Title: Biochimica et Biophysica Acta (BBA) - Biomembranes; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.bbamem.2016.07.018; Content Type: article; Copyright: © 2016 The Authors. Published by Elsevier B.V.
• Contract Date: May 8, 2019