Avtor/Urednik		Zuvic-Butorac, Marta; Mueller, Peter; Pomorski, Thomas; Libera, Jeanette; Herrmann, Andreas; Schara, Milan
Naslov		Lipid domains in the exoplasmic and cytoplasmic leaflet of the human erythrocyte membrane: a spin label approach
Tip		članek
Vir		Eur Biophys J
Vol. in št.		Letnik 28
Leto izdaje		1999
Obseg		str. 302-11
Jezik		eng
Abstrakt		The existence of different lipid domains in the monolayers of the human erythrocyte membrane was investigated at 4 degree C by employing spinlabelled phospholipid analogues. Spectra of analogues located exclusively either in the exoplasmic or in the cytoplasmic leaflet of erythrocyte membranes were recorded. Spectra were simulated by variation of order parameter describing the average amplitude of motion of the long molecular axis of the nitrogen 2p pi orbital of the spin label and of the respective correlation times. For both leaflets at least three components were required to fit the experimental spectra, differing mainly in the order parameter. While the parameters of each component are not very different between both membrane halves, the relative contribution of each component to the spectrum is different between the exoplasmic and cytoplasmic leaflet. The order parameter of the most fluid component, presumably resembling the lipid bulk phase, is smaller in the cytoplasmic leaflet in comparison to the exoplasmic one. The lateral coexistence of different lipid domains in the human red blood cell membrane is con- cluded. The molecular nature of those domains is discussed.
Deskriptorji		ERYTHROCYTE MEMBRANE PHOSPHOLIPIDS SPIN LABELS MEMBRANE LIPIDS CELL MEMBRANE SPHINGOMYELINS