Effect of salt concentration on membrane lysis pressure

Cell membranes are capable of withstanding significant osmotic stress, the exact amount of which varies with the lipid composition. In this paper, we examine the effect that salt concentration has on the lysis pressure of membranes containing anionic lipids. Vesicles containing varying amounts of phosphatidylcholine and phosphatidylglycerol were osmotically stressed using NaCl as the osmolyte. The lysis pressure was observed to vary linearly with the Debye screening length and the extent of the variation was linear with anionic lipid content. The implications these results have for cells that frequently encounter low solute environments are discussed.