title: Bacteriorhodopsin, boundary lipid and protein conformers: a spin label study.
abstract: A spin label study, as a function of temperature, has been made with the bacteriorhodopsin membrane using a stearic acid spin label. The ESR spectra show a strong variation with temperature and the presence of isosbestic points. The spectra are interpreted as indicating the presence of a two-component system with an activation energy (approx. 14 kcal/mol) corresponding to a protein conformational change. This activation energy is similar to that deduced from recent flash photolysis studies. It is concluded that the spin label is sensitive to the temperature-dependent protein conformational change in this membrane system.
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D001436:Bacteriorhodopsins / Q000378:metabolism*; D002338:Carotenoids / Q000378:metabolism*; D006217:Halobacterium / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D011487:Protein Conformation; D013113:Spin Labels; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D008563:Membrane Lipids; D008565:Membrane Proteins; D013113:Spin Labels; D002338:Carotenoids; D001436:Bacteriorhodopsins