LLP peptides form α-helices in the presence of lipid. Circular dichroism spectroscopy of LLP peptides in PO4 buffer (open squares) and in the presence of 90%POPC:10%POPG (filled squares). Spectroscopic analysis revealed that each peptide possessed the characteristic minima at 208 nm and 222 nm indicating α-helical character. (a) LLP-1 labeled with NBD; (b) LLP-2 labeled with NBD; (c) LLP-3; (d) LLP-1D labeled with NBD. (e) The percent α-helicity was calculated from the CD spectroscopy curves in figure a-d for each peptide using the following formula: Θ222/(1–2.5/n)(40,000), where n = the number of residues present in the peptide.