This research project propose to study the relationship between structure and function of three membrane proteins: bacteriorhodopsin, rhodopsin and melibiose transporter. New information on the conformational changes induced during the photocycle of bacteriorhodopsin and rhodopsin, as well as the role of helix-helix interactions in the maintenance of the bacterirohodopsin structure are expected to be obtained by the use of FTIR and DSC. The effect of lipid fluidity on the rhodopsin activation will also be investigated. Using site-directed mutagenesis, we expect: a) to determine which Asp or Glu residues are involved in the cation binding to the purple membrane; b) to study the interaction of transducin (G protein) upon lightf excitation with an hybridized form of bacteriorhodopsin which will contain one or two citoplasmatic loops changed by the homologous loops of rhodopsin. With reference to the melibiose transporter, we propose to use FTIR and DSC to study the conformatiional changes induced by Na\super +\nosuper and melibiose binding. The reconstitution of the protein from fragments will be also studied in liposomes.
|Effective start/end date||1/11/96 → 1/11/99|
- Dirección General de Investigación Científica y Técnica (DGICYT)