| Regional Biophysics Meeting 2005, March 16-20, Zreče, Slovenia | [MembBiophys] |
Membrane surface glycosylation has been discovered many years ago, still its detailed molecular mechanism of its function remains unclear. It is known, that glycosylation of membrane proteins can represent active sites in signal and/or ligand recognition and/or transduction processes. However, the recent EPR spin-labeling studies have shown that also lipid glycosylation can play an important role. It can interact with lateral lipid domains and change their polarity and motional properties, and vice versa, also the lipid domains, i.e. their motional properties can induce carbohydrate aggregation and modify the mobility of the surface polysaccharides. According to these properties the coupled glycocalyx and lipid domains can transfer some biological information (like high local concentration of some polar molecules or induced phase separation of any kind of membrane constituents). To explore these possibilities we performed extensive membrane lateral heterogeneity characterization on different model membranes. In order to determine membrane properties within lipophylic part and on the membrane surface various spin labels anchored in model membranes were involved (MeFASL series, GluSlStearate). To obtain biologically relevant information the model membranes were reconstituted from lipid mixtures that include different lipids, cholesterol, glycolipids and sphyngolipids. To determine membrane lateral domain structures (within lipophylic part and on membrane surface) in a statistically relevant way spectral simulation method combined with multiple-HEO optimization and GHOST condensation were applied.
Email: iztok.dogsa@ijs.si
Address: Laboratory of biophysics - EPR center,, Jozef Stefan Institute,, Jamova 39,, SI-1000 Ljubljana, Slovenia