title: NMR evidence for helix geometry modifications by a G-U wobble base pair in the acceptor arm of E. coli tRNA(Ala).
abstract: A ribooligonucleotide duplex representing the acceptor stem of E. coli RNA(Ala) with a G3-U70 wobble base pair, which is the main identity element for the recognition by the alanine-tRNA synthetase, has been characterized by 2D-NMR, as having two sequence variants with a regular Watson-Crick G3-C70 and an I3-U70 wobble pair, respectively. As compared to a regular A-RNA, the G-U base pair gives rise to variations of the local helix geometry which are reflected in distinct local chemical shift changes. Structural differences between the duplex possessing an I3-U70 base pair and the wild-type G3-U70 sequence have also been found. The nucleotides in the ubiquitous single-stranded NCCA terminus display a surprisingly high degree of stacking order, especially between A73, C74, and C75.
authors.affiliation: Laboratorium für Biochemie der Universität Bayreuth, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Limmer
authors.forename: B
authors.initials: B
authors.lastname: Reif
authors.forename: G
authors.initials: G
authors.lastname: Ott
authors.forename: L
authors.initials: L
authors.lastname: Arnold
authors.forename: M
authors.initials: M
authors.lastname: Sprinzl
mesh_terms: D001482:Base Composition; D001483:Base Sequence; D004926:Escherichia coli / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009843:Oligoribonucleotides / Q000138:chemical synthesis / Q000737:chemistry; D017354:Point Mutation; D012329:RNA, Bacterial / Q000737:chemistry* / Q000235:genetics; D012344:RNA, Transfer, Ala / Q000737:chemistry* / Q000235:genetics
chemical_list: D009843:Oligoribonucleotides; D012329:RNA, Bacterial; D012344:RNA, Transfer, Ala