The interaction of dipole modifiers with polyene-sterol complexes

PLoS One. 2012;7(9):e45135. doi: 10.1371/journal.pone.0045135. Epub 2012 Sep 21.

Abstract

Recently, we showed that the effect of dipole modifiers (flavonoids and styrylpyridinium dyes) on the conductance of single amphotericin B (AmB) channels in sterol-containing lipid bilayers primarily resulted from changes in the membrane dipole potential. The present study examines the effect of dipole modifiers on the AmB multi-channel activity. The addition of phloretin to cholesterol-containing membranes leads to a significant increase in the steady-state AmB-induced transmembrane current. Quercetin significantly decreases and RH 421 increases the current through ergosterol-containing bilayers. Other tested flavonoids and styrylpyridinium dyes do not affect the channel-forming activity of AmB independently on the sterol composition of the bilayers. The effects obtained in these trials may instead be attributed to the direct interaction of dipole modifiers with AmB/sterol complexes and not to the effect of dipole potential changes. The presence of double bonds in the Δ7 and Δ22 positions of sterol molecules, the number of conjugated double bonds and amino sugar residues in polyene molecules, and the conformation and adsorption plane of dipole modifiers are important factors impacting this interaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amphotericin B / chemistry
  • Coloring Agents / chemistry
  • Electricity*
  • Flavonoids / chemistry
  • Ion Channel Gating
  • Lipid Bilayers / chemistry
  • Polyenes / chemistry*
  • Sterols / chemistry*

Substances

  • Coloring Agents
  • Flavonoids
  • Lipid Bilayers
  • Polyenes
  • Sterols
  • Amphotericin B

Grants and funding

This work was partly supported by the Russian Foundation for Basic Research, the Program “Molecular and Cell Biology”, the Russian Academy of Sciences, the grant of the President of RF (# MK-1813.2012.4) and Russian state contract (MES, FTP<>). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.