Naslov
Transmembrane heterogeneity in the erythrocyte membrane

Autori
Marić-Brumini, Gordana ; Schara, Milan

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, ostalo

Izvornik
11th Meeting of the European Association for Red Cell Research / Svetina, Saša - Ljubljana : Birografika Bori, 1997, 31-31

Skup
11th Meeting of the European Association for Red Cell Research

Mjesto i datum
Gozd Martuljek, Slovenija, 17.04.1997. - 21.04.1997

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
transmembrane heterogeneity; erythrocytes; electron paramagnetic resonance

Sažetak
Molecular order and dynamics variation across membranes has been proven by several experimental approaches. It should be stressed that besides the pioneering disclosure of transmembrane heterogeneity by EPR and spin labeling, it is this technique which shows to be capable of exploring the biomembrane structures in situ in nondestructed cells. We tried to describe the discontinuities which appeared in molacular ordering and dynamics for the particular segments of the lipid acyl chain in erythrocytes, which were detected in the temperature dependence study of erythrocytes. Bovine and human erythrocytes were labeled selectively to probe the membrane across the bilayer by tailored spin probes - methyle esters of palmitic acid with the nitroxide attached at different positions of the acyl chain. The temperature dependencies of the molecular order show typical softening i.e. at given temperature the normal temperature depreciation of the molecular order starts to decay with an increased rate. Approaching the bilayer center the chain softening characteristic temperature is shifted to lower values. These local "chain melting" temperatures are an interesting phenomenon by which the lipidphase can be characterised. Such local differences in the lipid segmental order and dynamics might precondition the environment of the membrane included enzymes, channelc or other membrane structures. Herewith the proper conformation, across the membrane, of such structures is provided in order to sustain the optimal operation of the cell. There are differences in the cross membrane melting shifts beteen the bovine and human erythrocytes, which probably could be ascribed to the specific lipid composition of these cells.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA