NMR evidence for helix geometry modifications by a G-U wobble base pair in the acceptor arm of E. coli tRNA(Ala).
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.
Limmer
S
S
Laboratorium für Biochemie der Universität Bayreuth, Germany.
Reif
B
B
Ott
G
G
Arnold
L
L
Sprinzl
M
M
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
D009843:Oligoribonucleotides; D012329:RNA, Bacterial; D012344:RNA, Transfer, Ala