title: [Characterization of fluorescent derivatives of tRNA Phe by experiments in the ribosomal system].
abstract: Yeast tRNAPhe has been modified by excising the Y base and by replacing the Y base or the dihydrouracil residue with the fluorescent dyes proflavine or ethidium bromide. The poly(U) directed ribosomal system from E. coli was used to study the activities of the tRNAPhe derivatives in the assays for ribosome binding and polyphenylalanine synthesis. It was found that the tRNAPhe derivatives modified by replacing dihydrouracil were nearly as active as unmodified tRNAPhe. While excision of the Y base led to a considerable decrease in the activities, replacement by the above mentioned dyes yielded rather active tRNAPhe derivatives. The activities decreased somewhat when the tRNAPhe derivatives with a substitution in the anticodon loop were reduced with NaBH4. The lower plateau values observed with some of the tRNAPhe derivatives are largely attributed to a decreased efficiency of tRNA binding to the ribosomes which, in turn, results in an increased susceptibility to deacylation prior to phenylalanine transfer.
mesh_terms: D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D010649:Phenylalanine; D014176:Protein Biosynthesis / Q000187:drug effects; D012343:RNA, Transfer / Q000032:analysis / Q000378:metabolism*; D012441:Saccharomyces cerevisiae; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship
chemical_list: D010649:Phenylalanine; D012343:RNA, Transfer; D008274:Magnesium
vernacular_title: Aktivnost' fluorestsiruiushchikh proizvodnykh tRNK Phe b ribosomnoĭ sisteme