EFFECT OF GLYCOLIPIDS ON THE PHASE-BEHAVIOR AND DYNAMIC PROPERTIES OF PHOSPHOLIPID LIPOSOMES

The glycolipids of Acholeplasma laidlawii AIHO89 membranes were identified and purified. The effect of monoglucosyldiacylglycerol(MGDG) and diglucosyldiacylglycerol(DGDG) on the thermotropic behavior of multilamellar vesicles of dipalmitoylphosphatidyl choline (DPPC), dipalmitoylphosphatidyl-glycerol(DPPG) has been investigated by high sensitivity differential scanning calorimetry. The main transition peaks were broadened, the enthalpies were decreased. DGDG caused the decrease in the transition temperatures of DPPC, DPPG liposomes by 3.08°C, 4.18°C, respectively. MGDG did not cause the alteration of the transition temperature of DPPC liposomes but caused the decrease of the transition temperatures of DPPG liposomes by 2.20°C. ESR experiments indicate that MGDG decreased the rotational correlation time of DPPC and DPPG liposomes. © 1992 Academic Press, Inc.