• Record: found
  • Abstract: found
  • Article: not found

Biomass production of site selective 13C/15N nucleotides using wild type and a transketolase E. coli mutant for labeling RNA for high resolution NMR

Read this article at

      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


      Characterization of the structure and dynamics of nucleic acids by NMR benefits significantly from position specifically labeled nucleotides. Here an E. coli strain deficient in the transketolase gene (tktA) and grown on glucose that is labeled at different carbon sites is shown to facilitate cost-effective and large scale production of useful nucleotides. These nucleotides are site specifically labeled in C1′ and C5′ with minimal scrambling within the ribose ring. To demonstrate the utility of this labeling approach, the new site-specific labeled and the uniformly labeled nucleotides were used to synthesize a 36-nt RNA containing the catalytically essential domain 5 (D5) of the brown algae group II intron self-splicing ribozyme. The D5 RNA was used in binding and relaxation studies probed by NMR spectroscopy. Key nucleotides in the D5 RNA that are implicated in binding Mg2+ ions are well resolved. As a result, spectra obtained using selectively labeled nucleotides have higher signal-to-noise ratio compared to those obtained using uniformly labeled nucleotides. Thus, compared to the uniformly 13C/15N-labeled nucleotides, these specifically labeled nucleotides eliminate the extensive 13C–13C coupling within the nitrogenous base and ribose ring, give rise to less crowded and more resolved NMR spectra, and accurate relaxation rates without the need for constant-time or band-selective decoupled NMR experiments. These position selective labeled nucleotides should, therefore, find wide use in NMR analysis of biologically interesting RNA molecules.

      Related collections

      Most cited references 50

      • Record: found
      • Abstract: found
      • Article: not found

      Oligoribonucleotide synthesis using T7 RNA polymerase and synthetic DNA templates.

      A method is described to synthesize small RNAs of defined length and sequence using T7 RNA polymerase and templates of synthetic DNA which contain the T7 promoter. Partially single stranded templates which are base paired only in the -17 to +1 promoter region are just as active in transcription as linear plasmid DNA. Runoff transcripts initiate at a unique, predictable position, but may have one nucleotide more or less on the 3' terminus. In addition to the full length products, the reactions also yield a large amount of smaller oligoribonucleotides in the range from 2 to 6 nucleotides which appear to be the result of abortive initiation events. Variants in the +1 to +6 region of the promoter are transcribed with reduced efficiency but increase the variety of RNAs which can be made. Transcription reaction conditions have been optimized to allow the synthesis of milligram amounts of virtually any RNA from 12 to 35 nucleotides in length.
        • Record: found
        • Abstract: found
        • Article: not found

        Crystal structure of a self-spliced group II intron.

        Group II introns are self-splicing ribozymes that catalyze their own excision from precursor transcripts and insertion into new genetic locations. Here we report the crystal structure of an intact, self-spliced group II intron from Oceanobacillus iheyensis at 3.1 angstrom resolution. An extensive network of tertiary interactions facilitates the ordered packing of intron subdomains around a ribozyme core that includes catalytic domain V. The bulge of domain V adopts an unusual helical structure that is located adjacent to a major groove triple helix (catalytic triplex). The bulge and catalytic triplex jointly coordinate two divalent metal ions in a configuration that is consistent with a two-metal ion mechanism for catalysis. Structural and functional analogies support the hypothesis that group II introns and the spliceosome share a common ancestor.
          • Record: found
          • Abstract: not found
          • Article: not found

          Natural abundance nitrogen-15 NMR by enhanced heteronuclear spectroscopy


            Author and article information

            Department of Chemistry and Biochemistry, Center for Biomolecular Structure and Organization, University of Maryland, 1115 Biomolecular Sciences Bldg (#296), College Park, MD 20742-3360 USA
            +1-301-4053516 , +1-301-3140386 ,
            J Biomol NMR
            Journal of Biomolecular Nmr
            Springer Netherlands (Dordrecht )
            29 November 2011
            29 November 2011
            February 2012
            : 52
            : 2
            : 103-114
            © The Author(s) 2011
            Custom metadata
            © Springer Science+Business Media B.V. 2012


            Comment on this article