Figure 3

Displacement of membrane cholesterol by Aβ(1–42) oligomers. Panels a and b illustrate how the positions of the labels in deuterated Chol were determined, in the presence and absence of Aβ(1–42), respectively. The solid black lines are the SLD profiles obtained with unlabelled Chol, and the solid red lines are the profiles with labelled Chol. The dotted lines are the corresponding difference (plus or minus peptide) profiles, and the dashed lines are best-fit single Gaussian fits to these difference profiles, showing peaks at 15.11 ± 0.39 Å from the bilayer centre (without peptide), and 17.06 ± 0.26 Å from the bilayer centre (with peptide), respectively (mean mid-peak positions ± SD). The errors bars show the 95% confidence intervals of the SLD profiles at the mid-difference profile positions. Panels c and d show similar difference profiles and fits without and with membrane Aβ(1–42) for the uniformly-labelled palmitoyl acyl chains of POPC, with similar figure labelling.