Antimicrobial peptide dendrimer interacts with phosphocholine membranes in a fluidity dependent manner: a neutron reflection study combined with molecular dynamics simulations.

Research output: Contribution to journalArticle

Abstract

The interaction mechanism of a novel amphiphilic antimicrobial peptide dendrimer, BALY, with model lipid bilayers was explored through a combination of neutron reflection and molecular dynamics simulations. 1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1,2-dipalmitoyl-sn-glycero-3-phos-phocholine (DPPC) lipid bilayers were examined at room temperature to extract information on the interaction of BALY with fluid and gel phases, respectively. Furthermore, a 1:4 mixture of POPC and DPPC was used as a model of a phase-separated membrane. Upon interaction with fluid membranes, BALY inserted in the distal leaflet and caused thinning and disordering of the headgroups. Membrane thinning and expansion of the lipid cross-sectional area was observed for gel phase membranes, also with limited insertion to the distal leaflet. However, dendrimer insertion through the entire lipid tail region was observed upon crossing the lipid phase transition temperature of DPPC and in phase separated membranes. The results show clear differences in the interaction mechanism of the dendrimer depending on the lipid membrane fluidity, and suggest that a role for lipid phase separation in promoting its antimicrobial activity.

Details

Authors
  • Tania Lind
  • L Darré
  • C Domene
  • Z Urbanczyk-Lipkowska
  • M Cárdenas
  • H P Wacklin
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Biological Sciences
Original languageEnglish
Pages (from-to)2075-2084
JournalBiochimica et biophysica acta
Volume1848
Issue number10
Publication statusPublished - 2015
Publication categoryResearch
Peer-reviewedYes