| Popis: |
Two sulfhydryl groups of bovine rhodopsin, available for chemical modification only after bleaching, were specifically labeled with radioactive iodoacetamide. The labeled protein was extensively reduced and alkylated and digested with pronase, and peptides were purified by gel filtration chromatography, anion and cation exchange chromatography, and high pressure liquid chromatography. Purified peptides were detected by their radioactivity, UV spectral properties, and by their fluorescence after reaction with fluorescamine. Sequence analysis of a highly purified peptide established the sequence S-carboxamido[14C]methyl cysteinyl-prolyl-glycine as the site of one of the light-exposed sulfhydryl groups of bovine rhodopsin. |
