title: Physical and coding properties of poly(5-aminouridylic acid) and of 5-aminouridine-containing trinucleotides.
abstract: This report concerns the synthesis of poly(5-aminouridylic acid) and of 5-aminouridine-containing trinucleotides. Starting from 5-aminouridine the nucleoside 5'-phosphate was prepared enzymatically with carrot phosphotransferase whereas the nucleoside 5'-diphosphate was prepared chemically and polymerised with polynucleotide phosphorylase. The aminouridine-containing trinucleotides were prepared by known enzymatic procedures. Besides an increase of stability in the secondary structure poly(nh25U) forms a triple-stranded complex with poly(A) and stimulates the poly(Phe) synthesis like poly(U). In contrast to U-nh25U-U, the triplet containing the 3'-terminal aminouridine does not stimulate the binding of Phe-tRNA to 70-S ribosomes. This behavior is discussed with respect to the influence of a modification on the stacking geometry of a codon and the base pairing scheme between the 5'-nucleotide of the anticodon and the 3'-nucleotide of the condon.
mesh_terms: D004926:Escherichia coli / Q000378:metabolism; D007700:Kinetics; D008837:Micrococcus / Q000378:metabolism; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D009841:Oligonucleotides / Q000096:biosynthesis*; D010770:Phosphotransferases; D010944:Plants / Q000201:enzymology; D011072:Poly U / Q000031:analogs & derivatives*; D011117:Polyribonucleotide Nucleotidyltransferase; D014176:Protein Biosynthesis; D012270:Ribosomes / Q000378:metabolism; D014529:Uridine / Q000031:analogs & derivatives
chemical_list: D009841:Oligonucleotides; D011072:Poly U; D010770:Phosphotransferases; D011117:Polyribonucleotide Nucleotidyltransferase; D014529:Uridine