1-Palmitoyl-2-pyrenedecanoyl glycerophospholipids as membrane probes: evidence for regular distribution in liquid-crystalline phosphatidylcholine bilayers.

摘要: We have synthesized 1-palmitoyl-2-pyrenedecanoyl-sn-glycero derivatives of 3-phosphatidylcholine, 3-phosphatidylethanolamine, 3-phosphatidylserine, 3-phosphatidylglycerol, 3-phosphatidylinositol, and 3-phosphatidic acid investigated their behavior in monolayers neat mixed bilayers. Fluorescence spectroscopy pyrene phospholipid dispersions revealed a well-defined thermotropic transition at 13.5-19 degrees C depending on the polar head group. An endotherm coinciding with this was observed differential scanning calorimetry, indicating it to be due melting lipid acyl chains. For pyrenephosphatidylethanolamine, much higher temperature (70 C). Compression isotherms obtained an argon/water interface that moiety somewhat increases mean molecular area molecule but does not prevent expression head-group-dependent packing behavior. Partition lipids between coexisting fluid solid phases fluorometry calorimetry. Both techniques indicate these prefer phase preference is independent The rates apparent activation energies lateral diffusion bilayers were found similar for most lipids, suggesting movement phospholipids critically dependent interactions head-group level. Lateral distribution gel phosphatidylcholine studied excimer technique In gel-state dipalmitoylphosphatidylcholine bilayers, form clusters. These clusters, however, do consist pure aggregates (compounds) labeled unlabeled lipid.(ABSTRACT TRUNCATED AT 250 WORDS)