グラミシジンSとリン脂質膜の相互作用に関する熱的研究

抄録

The interactions between lipid membranes composed of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine (DPPE) and a polypeptide antibiotic, gramicidin S (GS), were investigated by means of differential scanning calorimetry (DSC). With increasing the GS composition, new membrane phases, which exhibited phase transitions at lower temperature than that of the pure lipid membranes, were formed. On the basis of the phase rule, these new membrane phases were considered to be lattice complexes of GS and lipids. By NMR measurement, the molecular motion of DPPC associated with GS was found to be considerably elevated. The interactions between GS and membranes composed of mixed lipids, DPPC and DPPE, were also studied.