Smoothed acyl chain orientational order parameter profiles in dimyristoylphosphatidylcholine-distearoylphosphatidylcholine mixtures: a 2H-NMR study
| Autor: | I. Vavasour, Michael R. Morrow, Dalian Lu |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Magnetic Resonance Spectroscopy
Lipid Bilayers 030303 biophysics Analytical chemistry Biophysics Plateau (mathematics) 03 medical and health sciences chemistry.chemical_compound Liquid crystal Phase (matter) Stearates Methylene 030304 developmental biology 0303 health sciences Chemistry Bilayer technology industry and agriculture Deuterium Crystallography Order (biology) Acyl chain Phosphatidylcholines lipids (amino acids peptides and proteins) Dimyristoylphosphatidylcholine Research Article |
| Zdroj: | Biophysical Journal. 68(2):574-583 |
| ISSN: | 0006-3495 |
| DOI: | 10.1016/s0006-3495(95)80219-5 |
| Popis: | The accommodation of chain-length mismatch in liquid crystal phase bilayers was examined by using deuterium nuclear magnetic resonance to obtain smoothed orientational order parameter profiles for acyl chains of both components in binary lipid mixture bilayers. Mixtures of dimyristoylphosphatidylcholine (DMPC) and distearoylphosphatidylcholine (DSPC) covering a range of compositions were prepared with either DSPC acyl chains or DMPC acyl chains perdeuterated. Orientational order parameters in the plateau regions of the smoothed profiles for both components were found to increase smoothly with increasing DSPC concentration. The orientational order parameters in the DSPC-smoothed profile were found to be slightly higher than corresponding values for DMPC over a wide range of bilayer composition. The shapes of the smoothed profiles for both components were found to be sensitive to bilayer composition. At low DSPC concentration, DSPC methylene deuterons near the bilayer center display a secondary plateau at low orientational order. At high DSPC concentration, the plateau of the DMPC-smoothed profile is stretched slightly. The concentration dependence of the smoothed profiles at low DSPC concentration appears to be consistent with a picture in which the last few segments of the DSPC chain cross the bilayer midplane, on average, but remain very disordered. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|