2017 journal article

Single channel planar lipid bilayer recordings of the melittin variant MelP5

Biochimica Et Biophysica Acta (BBA)-Biomembranes.

author keywords: Antimicrobial peptide; Pore-forming peptide; Melittin; MelP5; Planar lipid bilayer
MeSH headings : Amino Acid Sequence; Amino Acids / metabolism; Bee Venoms / metabolism; Cholesterol / metabolism; Lipid Bilayers / metabolism; Liposomes / metabolism; Melitten / metabolism; Membranes / metabolism; Peptides / metabolism; Phosphatidylcholines
TL;DR: Electrophysiological comparison between MelP5 and melittin using planar lipid bilayer recordings reveals thatMelP5 pores in lipid membranes composed of 3:1 phosphatidylcholine:cholesterol consist of an average of 10 to 12 monomers compared to anAverage of 3 to 9 monomers for melittIn, but both peptides form transient pores with dynamically varying conductance values similar to previous findings formelittin. (via Semantic Scholar)
Source: ORCID
Added: August 19, 2022

MelP5 is a 26 amino acid peptide derived from melittin, the main active constituent of bee venom, with five amino acid replacements. The pore-forming activity of MelP5 in lipid membranes is attracting attention because MelP5 forms larger pores and induces dye leakage through liposome membranes at a lower concentration than melittin. Studies of MelP5 have so far focused on ensemble measurements of membrane leakage and impedance; here we extend this characterization with an electrophysiological comparison between MelP5 and melittin using planar lipid bilayer recordings. These experiments reveal that MelP5 pores in lipid membranes composed of 3:1 phosphatidylcholine:cholesterol consist of an average of 10 to 12 monomers compared to an average of 3 to 9 monomers for melittin. Both peptides form transient pores with dynamically varying conductance values similar to previous findings for melittin, but MelP5 occasionally also forms stable, well-defined pores with single channel conductance values that vary greatly and range from 50 to 3000pS in an electrolyte solution containing 100mM KCl.