The permeabilization of liposomes by melittin,an antimicrobial peptide(AMP),has been studied by an electrochemiluminescence(ECL)imaging strategy.The methodology consisted ffrst of encapsulating ECL reagents in sealed ...The permeabilization of liposomes by melittin,an antimicrobial peptide(AMP),has been studied by an electrochemiluminescence(ECL)imaging strategy.The methodology consisted ffrst of encapsulating ECL reagents in sealed giant asymmetrical liposomes(100μm in diameter)made of DOPG/DOPC phospholipids(i.e.,1,2-dioleoyl-sn-glycerol-3-phospho-(1′-rac-glycerol)sodium salt/1,2-dioleolyl-sn-glycero-3-phosphocholine).Then liposomes were placed on an indium tin oxide electrode coated with poly-L-lysine to avoid any membrane poration/permeabilization through polarization of the electrode surface.Finally,the addition of melittin(from 10μM to 100 nM in concentration)enabled the permeabilization of the lipid membrane followed by the liposome content release and subsequent light generation through the ECL reagents oxidation processes.Interestingly,at a melittin concentration of 10μM,two successive leakages occurring on the same liposome could be imaged.Combination of ECL and photoluminescence imaging allowed comprehensive monitoring of the permeabilization and content release of a single liposome.This ECL imaging approach opens interesting perspectives to characterize the instant release of vesicle content upon permeabilization by AMPs or other membrane-active species.展开更多
基金supported in parts by CNRS UMR 8640,Ecole Normale Supérieure,PSL University and Sorbonne Université.F.B.T.thanks the doctoral school ED388“Chimie Physique et de Chimie Analytique de Paris Centre”for a PhD grant.We thank Gilles Clodic(MS3U platform,Sorbonne Université)for MALDI-TOF mass spectrometry analysis.N.S.acknowledges the financial support from Agence Nationale de la Recherche(ELISE-ANR-21-CE42).
文摘The permeabilization of liposomes by melittin,an antimicrobial peptide(AMP),has been studied by an electrochemiluminescence(ECL)imaging strategy.The methodology consisted ffrst of encapsulating ECL reagents in sealed giant asymmetrical liposomes(100μm in diameter)made of DOPG/DOPC phospholipids(i.e.,1,2-dioleoyl-sn-glycerol-3-phospho-(1′-rac-glycerol)sodium salt/1,2-dioleolyl-sn-glycero-3-phosphocholine).Then liposomes were placed on an indium tin oxide electrode coated with poly-L-lysine to avoid any membrane poration/permeabilization through polarization of the electrode surface.Finally,the addition of melittin(from 10μM to 100 nM in concentration)enabled the permeabilization of the lipid membrane followed by the liposome content release and subsequent light generation through the ECL reagents oxidation processes.Interestingly,at a melittin concentration of 10μM,two successive leakages occurring on the same liposome could be imaged.Combination of ECL and photoluminescence imaging allowed comprehensive monitoring of the permeabilization and content release of a single liposome.This ECL imaging approach opens interesting perspectives to characterize the instant release of vesicle content upon permeabilization by AMPs or other membrane-active species.
