title: Lipid-protein interaction in frog nerve membrane as studied by spin-labelling.
abstract: Molecular dynamics of membrane proteins in frog nerve was studied by the spin labelling technique. By varying the reaction conditions three protein domains were identified which differ in polarity of the micro-environment of the labelled sites (polarity index, h = 0, 0.6 and 1.2) and in mobility (apparent rotational correlation times, tau 2 = 1 ns, 35 ns and 62 ns, respectively). The protein domains reflect different structural stabilities towards specific and non-specific membrane perturbants. One part of the labels has an anisotropic distribution. Modification of the membrane components with different chemicals leads to a change in conformation and/or segmental motion of proteins, as well as to an alteration in the degree of ordering of the attached labels. The experiments support the fact, that the state of the lipid matrix strongly influences the overall conformation of the embedded proteins and their functions in biological processes.
mesh_terms: D000777:Anesthetics / Q000494:pharmacology; D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology; D004578:Electron Spin Resonance Spectroscopy; D066298:In Vitro Techniques; D008301:Maleimides; D008563:Membrane Lipids / Q000032:analysis* / Q000378:metabolism; D008565:Membrane Proteins / Q000032:analysis* / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000378:metabolism; D010640:Phenothiazines; D011487:Protein Conformation; D011893:Rana esculenta; D013113:Spin Labels
chemical_list: D000777:Anesthetics; D014150:Antipsychotic Agents; D008301:Maleimides; D008563:Membrane Lipids; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D010640:Phenothiazines; D013113:Spin Labels