Figure 3.

MD simulations with POPG and POPC lipids.A and C, normalized number of contacts between ELIC residues and headgroups of the POPG/POPC lipids from coarse-grained simulations. A contact was assumed if a residue’s bead was within 5.5 Å of the lipid headgroup’s bead and the contacts were subsequently averaged across the five subunits. Residues with a contact frequency of >33% are colored red. Residue indices corresponding to structural elements are highlighted in gray and important residues within them are highlighted and illustrated in the inset. B and D, densities of the different PG/PC lipids calculated from CG simulations illustrated at one of the subunit interfaces at an isosurface value of 1.9 molecules/nm³ and 5.0 molecules/nm³, respectively. For POPG, the R286, R299, and R301 residues mediating interactions with the anionic lipid are illustrated. For POPC, the M1-helix W206 residue adjacent to the preferential residence site is illustrated. Additionally, the detergent molecule identified to bind at this site in the PDB structure 6hjx is overlaid on the subunit interface and illustrated in yellow.