Fig. 3. PC/PE ratio modulates the partitioning of model AH and HD peptides.

a Helical wheel representation of KWALP20 and PL108-AH, generated from HeliQuest⁶⁹. b Distribution of KWALP20 and PL108 in DOPE or DOPC/DOPE (1:1) DIBs. KWALP20 is labeled with and PL108 with NBD. Scale bar: 50 µm. The partition coefficient is plotted for both peptides as box-plots (box limits, upper and lower quartiles; middle line, median; whiskers, minimum and maximum value), from n = 4 independent measurements for each condition. Individual data are shown as black dots. c FRAP experiment shows that KWALP20 (purple) and lipid (green) signals are mobile at the monolayer. NBD-PE reports for phospholipids. Yellow arrows indicate the area bleached. Scale bar: 50 µm. Recovery half-time was obtained using one-phase association fitting in GraphPad software and is shown in the upper right box. d KWALP20 distribution in DIBs of different PC/PE ratio. Line profiles (not displayed) are drawn perpendicular to the bilayer and monolayers (as described in Fig. 2b); the thickness of the line is 30-40% of the bilayer size. The corresponding signals are shown in the box (right); black arrows depict the bilayer signal. Scale bar: 20 µm. e Partition coefficient of KWALP20 in DIBs of different DOPC/DOPE ratios represented as box-plots (box limits, upper and lower quartiles; middle line, median; whiskers, minimum and maximum value). Sample size was n = 31 for 0% PC, n = 14 for 10% PC, n = 18 for 20% PC, n = 41 for 30% PC, n = 16 for 40% PC and n = 28 for 50% PC. Each data point is plotted. f Relocalization of KWALP20 from the monolayer to the bilayer after addition of DOPC to DOPE DIBs. The bilayer signal is plotted over time. Image brightness is enhanced to improve bilayer viewing. Scale bar: 50 µm. Source data are provided as a Source Data file.