Neutron diffraction studies on selectively deuterated phospholipid bilayers
| Autor: | Anna Seelig, Hans Ulrich Gally, Giuseppe Zaccai, Joachim Seelig, G. Büldt |
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| Rok vydání: | 1978 |
| Předmět: |
Neutrons
Multidisciplinary Materials science Hydrogen Scattering Bilayer Neutron diffraction Phospholipid Molecular Conformation chemistry.chemical_element Membranes Artificial Pulmonary Surfactants Deuterium Crystallography chemistry.chemical_compound Membrane Lipids Membrane chemistry Molecule Scattering Radiation lipids (amino acids peptides and proteins) |
| Zdroj: | Nature. 271(5641) |
| ISSN: | 0028-0836 |
| Popis: | NEUTRON diffraction combined with the use of selectively deuterated lipids can provide detailed information on the molecular structure of membranes. Because of the large difference between the coherent scattering length of hydrogen ( −3.74 fermis) and deuterium (6.67 fermis) the deuterated membrane segments show up as intense peaks in the neutron density profile and can thus easily be located in the membrane1–3. We have applied this method to bilayer membranes of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), selectively deuterated at 12 different positions in the polar head group and the hydrocarbon chains. We report here that the mean position of the deuterated segments within the membrane can be determined in most cases to a precision of better than ±1 A. The average orientation of the phosphocholine group in the gel state as well as in the liquid crystalline state is almost parallel to the membrane surface. In the gel state the two hydrocarbon chains are out of step by about 1.8 A, and water penetrates up to the glycerol backbone of the lipid molecules. |
| Databáze: | OpenAIRE |
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