Interactions of the antimicrobial beta-peptide beta-17 with phospholipid vesicles differ from membrane interactions of magainins.
We have studied the interaction of beta-17, a potent synthetic antimicrobial beta-peptide, with phospholipids. We find that unlike other antimicrobial peptides such as magainin II, beta-17 facilitates the formation of nonbilayer phases, indicating that the peptide promotes negative curvature. Studies of liposomal leakage also indicate a different mode of membrane interaction relative to magainin II, but both leakage and membrane binding show that beta-17, like magainin II, has strong affinity for membranes containing anionic lipids. This is likely to be an important factor contributing to the antimicrobial specificity of the beta-peptide.
Epand
Raquel F
RF
Department of Biochemistry, McMaster University Health Sciences Centre, Hamilton, Ontario, Canada. epand@mcmaster.ca
Umezawa
Naoki
N
Porter
Emilie A
EA
Gellman
Samuel H
SH
Epand
Richard M
RM
D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000378:metabolism; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000378:metabolism; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry* / Q000378:metabolism; D002152:Calorimetry, Differential Scanning; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D002942:Circular Dichroism; D006801:Humans; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D015394:Molecular Structure; D010743:Phospholipids / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D008051:Lipid Bilayers; D010743:Phospholipids