title: A novel modified nucleoside found at the first position of the anticodon of methionine tRNA from bovine liver mitochondria.
abstract: Methionine tRNA was purified from bovine liver mitochondria, and its nucleotide sequence was determined. The tRNA possesses only three posttranscriptionally modified nucleosides, two pseudouridines in the anticodon and T stems and a previously unknown nucleoside specified by the gene sequence as cytidine, in the first position of the anticodon. Structure analysis of the anticodon nucleoside by mass spectrometry revealed a molecular mass 28 Da greater than that of cytidine, and unmodified ribose, with substitution at C-5 implied by hydrogen-deuterium exchange experiments. Proton NMR of the intact tRNA showed presence of a formyl moiety, thus leading to the candidate structure 5-formylcytidine (f5C), not a previously known compound. The structure assignment was confirmed by chemical synthesis and comparison of data from combined HPLC/mass spectrometry and proton NMR for the natural and synthetic nucleosides. The potential function of f5C in the tRNA(Met) anticodon is discussed with regard to codon-anticodon interactions.
authors.affiliation: Department of Industrial Chemistry, Faculty of Engineering, University of Tokyo, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Moriya
authors.forename: T
authors.initials: T
authors.lastname: Yokogawa
authors.forename: K
authors.initials: K
authors.lastname: Wakita
authors.forename: T
authors.initials: T
authors.lastname: Ueda
authors.forename: K
authors.initials: K
authors.lastname: Nishikawa
authors.forename: P F
authors.initials: PF
authors.lastname: Crain
authors.forename: T
authors.initials: T
authors.lastname: Hashizume
authors.forename: S C
authors.initials: SC
authors.lastname: Pomerantz
authors.forename: J A
authors.initials: JA
authors.lastname: McCloskey
authors.forename: G
authors.initials: G
authors.lastname: Kawai
mesh_terms: D000818:Animals; D000926:Anticodon; D001483:Base Sequence; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002855:Chromatography, Thin Layer; D003562:Cytidine / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry / Q000379:methods; D008930:Mitochondria, Liver / Q000737:chemistry*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009705:Nucleosides / Q000032:analysis* / Q000737:chemistry; D012313:RNA; D000077278:RNA, Mitochondrial; D012358:RNA, Transfer, Met / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D000926:Anticodon; D009705:Nucleosides; D000077278:RNA, Mitochondrial; D012358:RNA, Transfer, Met; C086073:5-formylcytidine; D003562:Cytidine; D012313:RNA