Figure 16.

Lipid exchange between the membrane-exposed pockets of MscS and the bilayer upon gating. (A) Cut away slices showing the packing of lipids in the pockets during the simulations of MscS in the closed (left) and open (right) states. Lipid molecules in the lower pocket reach the pore-sealing residues in the open state, but they are blocked in the closed state (insets). (B) A schematic model derived from the simulations showing that as pressure is applied, the increased lateral tension induces lipid repartitioning (blue arrows, left panel) from the protein pockets to the bilayer, destabilizing the closed state and facilitating the formation of the open state (orange arrow, left panel). Lipid molecules inside the pockets are highlighted with a green headgroup. Adapted with permission from ref 295. Copyright 2015 Springer Nature.