title: Isomeric phenylalanyl-tRNAs. Position of the aminoacyl moiety during protein biosynthesis.
abstract: The preparation of phenylalanyl-tRNA terminating in 3'-deoxyadenosine has been achieved by incubation of abbreviated tRNA (tRNA-CpC(OH)) with 3'-deoxyadenosine 5'-diphosphate and polynucleotide phosphorylase (EC 2.7.7.8), followed by aminoacylation. The isomeric phenylalanyl-tRNA terminating in 2'-deoxyadenosine was constructed by incubation of tRNA-CpC(OH) with 2'-deoxy-3'-O-phenylalanyladenosine 5'-diphosphate and polynucleotide phosphorylase. While tRNA is aminoacylated at the 2'-position, only the 3'-aminoacyl-tRNA is active as a peptide acceptor in the peptidyltransferase reaction. Both modified tRNAs were bound to the A-site as efficiently as unmodified tRNA, but neither was so efficient at P-site binding or as an acceptor in the peptidyltransferase reaction. Neither of the modified tRNAs acted as a donor in the peptidyltransferase reaction.
mesh_terms: D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism; D001665:Binding Sites; D003839:Deoxyadenosines; D004926:Escherichia coli; D007536:Isomerism; D010445:Peptide Elongation Factors; D010455:Peptides / Q000378:metabolism; D010649:Phenylalanine / Q000378:metabolism; D011117:Polyribonucleotide Nucleotidyltransferase; D014176:Protein Biosynthesis; D012316:RNA Nucleotidyltransferases / Q000378:metabolism; D012329:RNA, Bacterial; D012343:RNA, Transfer / Q000032:analysis; D012270:Ribosomes / Q000378:metabolism; D014316:Tritium
chemical_list: D003839:Deoxyadenosines; D010445:Peptide Elongation Factors; D010455:Peptides; D012329:RNA, Bacterial; D014316:Tritium; D010649:Phenylalanine; D012343:RNA, Transfer; D012316:RNA Nucleotidyltransferases; D011117:Polyribonucleotide Nucleotidyltransferase; D000604:Amino Acyl-tRNA Synthetases