title: Architecture of bacterial lipid A in solution. A neutron small-angle scattering study.
abstract: The phase structure of isolated bacterial lipid A, the lipid anchor of the lipopolysaccharides of the outer membrane of Gram-negative bacteria, has been investigated by neutron small-angle scattering. The shape of the scattering curves obtained at different H2O/2H2O ratios revealed a lamellar organisation of the lipid A at neutral pH both above and below its main phase temperature (approximately 40-45 degrees C). Analysis of the scattering curves and interpretation of the corresponding thickness distance distribution functions of the lamellar aggregates led to a model in which the lipid A molecules form a bilayer of about 5 nm in thickness. This value for the thickness of the bilayer, as well as the neutron-scattering density profile across the bilayer, can be explained by a molecular model which shows interdigitation of the fatty acid chains of the lipid A.
authors.affiliation: Robert Koch-Institut des Bundesgesundheitsamtes, Berlin.
authors.forename: H
authors.initials: H
authors.lastname: Labischinski
authors.forename: E
authors.initials: E
authors.lastname: Vorgel
authors.forename: W
authors.initials: W
authors.lastname: Uebach
authors.forename: R P
authors.initials: RP
authors.lastname: May
authors.forename: H
authors.initials: H
authors.lastname: Bradaczek
mesh_terms: D006863:Hydrogen-Ion Concentration; D008050:Lipid A / Q000032:analysis*; D008051:Lipid Bilayers / Q000032:analysis; D008070:Lipopolysaccharides / Q000032:analysis; D008854:Microscopy, Electron; D008958:Models, Molecular; D015394:Molecular Structure; D009502:Neutrons; D012475:Salmonella / Q000032:analysis*; D012542:Scattering, Radiation; D012996:Solutions; D013696:Temperature
chemical_list: D008050:Lipid A; D008051:Lipid Bilayers; D008070:Lipopolysaccharides; D012996:Solutions