Figure 4.
Area per lipid in the presence of peptides as indicated, as a function of peptide:lipid ratio (P/L, mol/mol). The area per lipid molecule was derived from the order parameters obtained from 2H-NMR (Figure 2). The experimental errors of the area per lipid values were between 0.1 and 0.2 Å2, though the total errors are likely dominated by errors associated with the model assumptions underlying the area calculation. The dotted line indicates the area per lipid obtained for plain DMPC bilayers. Most peptides (Mag2, GS, BP100) induce an increase of the area per lipid. PGLa showed no influence up to a peptide:lipid ratio of 1:20, and also the PGLa/Mag2 mixture exhibited only a marginal increase of the area per lipid. TisB lead to a reduction of the area per lipid.