Electrochemiluminescence Imaging of Liposome Permeabilization by an Antimicrobial Peptide: Melittin

Fatma Ben Trad (1) , Jérôme Delacotte (1, 2) , Manon Guille-Collignon (1) , Frédéric Lemaître (1, 2) , Stéphane Arbault , Neso Sojic , Fabienne Burlina , Eric Labbé (1, 2) , Olivier Buriez (1)

1 PASTEUR - Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640)
2 SU - Sorbonne Université

The permeabilization of liposomes by melittin, an antimicrobial peptide (AMP), has been studied by an electrochemiluminescence (ECL) imaging strategy. The methodology consisted first of encapsulating ECL reagents in sealed giant asymmetrical liposomes (100 µm 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 10 µM 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 10 µM, 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.

Mots clés: Electrochemiluminescence (ECL); Liposome; ECL Imaging; Permeabilization; Membrane active peptide; Melittin

Domaines: Chimie

Fatma Ben Trad, Jérôme Delacotte, Manon Guille-Collignon, Frédéric Lemaître, Stéphane Arbault, et al.. Electrochemiluminescence Imaging of Liposome Permeabilization by an Antimicrobial Peptide: Melittin. Chemical & Biomedical Imaging, 2023, ⟨10.1021/cbmi.3c00003⟩. ⟨hal-04061359⟩