Interactions of the antimicrobial β-peptide β-17 with phospholipid vesicles differ from membrane interactions of magainins

Authors


R. M. Epand, Department of Biochemistry, 1200 Main Street West, McMaster University Health Sciences Centre, Hamilton, ON, L8N 3Z5 Canada. Fax: 905 521 1397, Tel.: 905 525 9140, E-mail: epand@mcmaster.ca

Abstract

We have studied the interaction of β-17, a potent synthetic antimicrobial β-peptide, with phospholipids. We find that unlike other antimicrobial peptides such as magainin II, β-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 β-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 β-peptide.

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