The aminosterol antibiotic squalamine permeabilizes large unilamellar phospholipid vesicles

We suggest that squalamine complexes with phospholipid to form a discrete structure within the bilayers of large unilamellar phospholipid vesicles, resulting in the transient leakage of small encapsulated molecules

Barry S Selinsky

2002

Scholarcy highlights

  • The ability of the shark antimicrobial aminosterol squalamine to induce the leakage of polar fluorescent dyes from large unilamellar phospholipid vesicles has been measured
  • Binding analyses based on the leakage data show that squalamine has its highest affinity to phosphatidylglycerol membranes, followed by phosphatidylserine and cardiolipin membranes
  • Fluorescent dye leakage generated by squalamine is graded, suggesting the formation of a discrete membrane pore rather than a generalized disruption of vesicular membranes
  • By using fluorescently labeled dextrans of different molecular weight, material with molecular weight ≤4000 g/mol is released from vesicles by squalamine, but material with molecular weight ≥10,000 is retained
  • Squalamine decreases the size of vesicles containing anionic phospholipid at a lower squalamine/lipid molar ratio than pure PC LUVs
  • We suggest that squalamine complexes with phospholipid to form a discrete structure within the bilayers of LUVs, resulting in the transient leakage of small encapsulated molecules
  • At higher squalamine/phospholipid ratios, these structures release from the bilayers and aggregate to form either new vesicles or squalamine/phospholipid mixed micelles

Need more features? Save interactive summary cards to your Scholarcy Library.