Fig. 3: Lipid-fibril interactions.
a Central slice of the unsharpened refined cryo-EM maps. b, d, f Superposition of the reconstructed cryo-EM maps and the atomic model. Sharpened, high-resolution maps are shown in magenta (b, L1A), violet (d, L1B), and red (f, L1C). Unsharpened, 4.5 Å low-pass filtered density is shown in gray. The backbone of the model is shown as black ribbon, with residues binding to the acyl chain (green) or choline moiety (blue) of phospholipids shown as spheres20. In (a, b, d, f) the arrows highlight non-fibrillar densities. c, e, g The grids indicate the probability density of the lipid acyl chain (dark green), phosphate (orange), and the choline nitrogen (blue), and sodium (purple), and chloride (light green) ions throughout MD simulations of the L1A (c), L1B, (e), and L1C (g) fibril. In (b–g) the right panels show a close-up view visualizing the ordered packing of the lipid molecules along the helical axis. h–j Probability density of the lipids throughout MD simulations of lipid diffusion for the L2A (h), L2B, (i), and L3A (j) fibril.
