These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Ribosomal protein L9: a structure determination by the combined use of X-ray crystallography and NMR spectroscopy.
    Author: Hoffman DW, Cameron CS, Davies C, White SW, Ramakrishnan V.
    Journal: J Mol Biol; 1996 Dec 20; 264(5):1058-71. PubMed ID: 9000630.
    Abstract:
    The structure of protein L9 from the Bacillus stearothernophilus ribosome has been determined at 2.5 A resolution by refinement against single crystal X-ray diffraction data with additional constraints provided by NMR data. This highly elongated protein consists of two domains separated by a nine-turn connecting helix. Conserved aromatic and positively charged amino acid residues on the surface of each domain are likely to be directly involved in binding 23 S ribosomal RNA. The shape of the protein, with its two widely spaced RNA-binding sites, suggests that it may serve as a "molecular strut", most likely playing a role in ribosome assembly and/or maintaining the catalytically active conformation of the ribosomal RNA. The combined use of X-ray and NMR data in the refinement procedure was essential in defining the N-terminal domain of the protein, which was relatively poorly determined by the X-ray data alone. In addition to resolving the ambiguities in defining the hydrophobic core and side-chain conformations with the N-terminal domain, this combined NMR-X-ray analysis provides the first detailed and accurate view of the N-terminal RNA-binding site. NMR data also showed that the N-terminal domain is stable in solution, indicated by amide protons that are protected from solvent exchange. The lack of definition of the N-terminal domain in the X-ray structure is therefore likely due to packing disorder within the crystal rather than structural instability. This combined NMR-X-ray analysis provides a useful model as to how X-ray and NMR data can be practically and logically combined in the determination of the structure of a single protein molecule.
    [Abstract] [Full Text] [Related] [New Search]