Models of haloadaptation in bacterial membranes

Abstract Cell membranes consist of a complex assortment of amphipathic lipids. These lipids exist in one of three phases in aqueous systems at the growth temperature of the organism: namely, lamellar gel, lamellar liquid-crystalline or hexagonal-II. The phase behaviour is modified by interaction of the lipids with other membrane components and electrolytes. A stable membrane structure is achieved when the polar and non-polar interactions are balanced such that a durable bilayer arrangement is formed into which the various membrane proteins are integrated. The effect of surface charge on phase domain behaviour of the membrane lipids and the modulation by electrolytes is crucial to understanding how halophiles adapt to high-salt environments.