Interaction of bee venom toxin melittin with ganglioside GM1 bicelle

•Percentage of melittin bound to GM1 bicelles is higher than that of control PC bicelles.•Percentage of melittin bound to GM1 bicelles is higher than that of GM1 micelles.•Melittin is fully α-helical in the presence of control PC bicelles.•In GM1 containing bicelles melittin becomes partially folded.•Lytic activity of melittin is less in the presence of GM1 bicelles than that of PC bicelles.

Melittin is a bee venom toxin that can act as antimicrobial peptide. Gangliosides are glycosphingolipids that help maintain membrane structure and organization as well as act as anchors for lectins, toxins, pathogens and antimicrobial peptides. Here we investigate interaction of melittin with fast tumbling isotropic control DMPC/CHAPS bicelles and ganglioside doped DMPC/CHAPS/GM1 bicelles. DOSY result shows that larger percentage of peptide binds to GM1 containing bicelles than that of the control PC bicelles. Bound peptide induces leakage of the bicelles entrapped carboxyfluorescein. Percentage of leakage is higher from control PC bicelles than that of the GM1 containing bicelles. In the presence of control PC bicelles melittin acquired fully α-helical structure. But in the presence of GM1 containing bicelles the peptide is not fully α-helical i.e., some random coil structure is present in this folded form. The present study shows that GM1 has an effect on membrane active antimicrobial peptide melittin.

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