Hydration of DMPC and DPPC at 4°C produces a novel subgel phase with convex–concave bilayer curvatures

摘要: Abstract Hydration of dimyristoyl- and dipalmitoylphosphatidylcholines at 4°C results in the formation a characteristic subgel phase designated Pcc. Examination by freeze-fracture electron microscopy shows convex–concave deformations planar bilayer which are two types. A smaller type with radius curvature about 20 nm predominates DMPC, larger 70 radii curvatures dominates DPPC. The Pcc can also be formed samples hydrated temperatures above main transition if dispersion is frozen slowly subsequently incubated for several days. was distinguished from Lc temperature transition, packing acyl chains on basis wide-angle X-ray diffraction, 2H-NMR spectra ‘solid-ordered’ phase. Vibrational carbonyl phosphate regions consistent partially reduced hydration state. origin deformation believed to result constraints imposed limiting headgroup frustration arising spontaneous both monolayers.