title: [The effect of modification of nucleotide-37 on the interaction of aminoacyl-tRNA with the A-site of the 70S ribosome].
abstract: To estimate the effect of modified nucleotide-37, the interaction of two yeast aminoacyl-tRNAs (Phe-tRNAK+YPhe and Phe-tRNAK-YPhe) with the A site of complex [70S.poly(U).deacylated tRNA(Phe) in the P site] was assayed at 0-20 degrees C. As comparisons with native Phe-tRNAK+YPhe showed, removal of the Y base decreased the association constant of Phe-tRNAK-YPhe and the complex by an order of magnitude at any temperature, and increased the enthalpy of their interaction by 23 kJ/mol. When the Y base was present in the anticodon loop of deacylated tRNA(Phe) bound to the P site of the 70S ribosome, twice higher affinity for the A site was observed for Phe-tRNAK-YPhe but not for Phe-tRNAK+YPhe. Thus, the modified nucleotide 3' of the Phe-tRNA(Phe) anticodon stabilized the codon-anticodon interaction both in the A and in the P sites of the 70S ribosome.
authors.affiliation: Konstantinov Institute of Nuclear Physics, Russian Academy of Sciences, Gatchina, Leningrad Oblast, 188300 Russia.
authors.forename: N G
authors.initials: NG
authors.lastname: Soboleva
authors.forename: V I
authors.initials: VI
authors.lastname: Makhno
authors.forename: A L
authors.initials: AL
authors.lastname: Konevega
authors.forename: Iu P
authors.initials: IuP
authors.lastname: Semenkov
authors.forename: V I
authors.initials: VI
authors.lastname: Katunin
mesh_terms: D000926:Anticodon; D001665:Binding Sites; D004926:Escherichia coli / Q000235:genetics; D016297:Mutagenesis, Site-Directed; D009711:Nucleotides / Q000235:genetics; D012346:RNA, Transfer, Amino Acyl / Q000235:genetics / Q000378:metabolism*; D012360:RNA, Transfer, Phe / Q000235:genetics / Q000378:metabolism; D012270:Ribosomes / Q000235:genetics / Q000378:metabolism*
chemical_list: D000926:Anticodon; D009711:Nucleotides; D012346:RNA, Transfer, Amino Acyl; D012360:RNA, Transfer, Phe