Bicontinuous inverted cubic phase formation as a predictor of antimicrobial and fusion peptide activity

Abstract

Some antimicrobial peptides (AMPs) and membrane fusion-catalyzing peptides (FPs) stabilize bicontinuous inverted cubic (QII) phases. Previous authors proposed a topological rationale for this correlation: AMP-induced pores, fusion intermediates, and QII phases all have negative Gaussian curvature (NGC). This rationale implicitly assumes that peptides change the curvature energy of lipid membranes. Here I test the proposed rationale, using simple models of the curvature energy of the QII phase and of the relevant intermediate structures.