Figure 6.

Characteristics of PDIP Analogues with Combined Modifications. (A) CD spectra were collected for 50 μM peptides in aqueous solution (100 mM NaF, 10 mM KH₂PO₄ pH 7.5) as above. (B) Resistance to breakdown by serum proteases was determined from the amount of peptide remaining after 24 h incubation with 25% (v/v) human serum as above. (C) Peptide–lipid binding was compared using SPR sensorgrams collected for 16 μM peptides binding to POPC/POPS (4:1) and POPC lipid bilayers as above. P/L at the end of the association phase (170 s) was used for comparing peptide–lipid binding affinity for POPC/POPS (4:1) compared to POPC membranes in (D). Peptide 3 is included, with dashed lines or shaded regions providing comparison in each of the plots.