title: Tritium thermal activation study of bacteriorhodopsin topography.
abstract: The action of thermally activated tritium on the purple membrane and delipidated bacteriorhodopsin fragments has been studied, tritium incorporation into specified amino acid residues being quantified by Edman degradation. The membrane environment was found to affect the accessibility of amino acid residues for tritium. Bacteriorhodopsin fragments 14-31, 45-63, 81-89, 171-179, and 210-225 were localized to the membrane interior while fragments 4-12, 32-44, 64-65, 73-80, and 156-170 should lie outside or close to membrane surface. It was demonstrated that the peptide fragments joining transmembrane rods are not fully exposed to the solution.
authors.affiliation: Shemyakin Institute of Bioorganic Chemistry, USSR Academy of Sciences, Moscow.
authors.forename: V I
authors.initials: VI
authors.lastname: Tsetlin
authors.forename: T N
authors.initials: TN
authors.lastname: Alyonycheva
authors.forename: V V
authors.initials: VV
authors.lastname: Shemyakin
authors.forename: L A
authors.initials: LA
authors.lastname: Neiman
authors.forename: V T
authors.initials: VT
authors.lastname: Ivanov
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001436:Bacteriorhodopsins / Q000032:analysis*; D003488:Cyanogen Bromide; D006358:Hot Temperature; D008565:Membrane Proteins / Q000032:analysis; D008958:Models, Molecular; D010446:Peptide Fragments / Q000302:isolation & purification; D013329:Structure-Activity Relationship; D014316:Tritium / Q000032:analysis*
chemical_list: D000596:Amino Acids; D008565:Membrane Proteins; D010446:Peptide Fragments; D014316:Tritium; D001436:Bacteriorhodopsins; D003488:Cyanogen Bromide