3gyq

Structure of the Thiostrepton-Resistance Methyltransferase S-adenosyl-L-methionine Complex

spinqualitylabelsall models 3gyq, resolution 2.45Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3gyq is a 2 chain structure with sequence from Streptomyces cyaneus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.45Å Ligands: SAM Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function TSNR_STRAJ Specifically methylates the adenosine-1067 in 23S ribosomal RNA. Confers resistance to antibiotic thiostrepton. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed The x-ray crystal structure of the thiostrepton resistance RNA methyltransferase (Tsr).S-adenosyl-L-methionine (AdoMet) complex was determined at 2.45-A resolution. Tsr is definitively confirmed as a Class IV methyltransferase of the SpoU family with an N-terminal "L30-like" putative target recognition domain. The structure and our in vitro analysis of the interaction of Tsr with its target domain from 23 S ribosomal RNA (rRNA) demonstrate that the active biological unit is a Tsr homodimer. In vitro methylation assays show that Tsr activity is optimal against a 29-nucleotide hairpin rRNA though the full 58-nucleotide L11-binding domain and intact 23 S rRNA are also effective substrates. Molecular docking experiments predict that Tsr.rRNA binding is dictated entirely by the sequence and structure of the rRNA hairpin containing the A1067 target nucleotide and is most likely driven primarily by large complementary electrostatic surfaces. One L30-like domain is predicted to bind the target loop and the other is near an internal loop more distant from the target site where a nucleotide change (U1061 to A) also decreases methylation by Tsr. Furthermore, a predicted interaction with this internal loop by Tsr amino acid Phe-88 was confirmed by mutagenesis and RNA binding experiments. We therefore propose that Tsr achieves its absolute target specificity using the N-terminal domains of each monomer in combination to recognize the two distinct structural elements of the target rRNA hairpin such that both Tsr subunits contribute directly to the positioning of the target nucleotide on the enzyme. Structure of the thiostrepton resistance methyltransferase.S-adenosyl-L-methionine complex and its interaction with ribosomal RNA.,Dunstan MS, Hang PC, Zelinskaya NV, Honek JF, Conn GL J Biol Chem. 2009 Jun 19;284(25):17013-20. Epub 2009 Apr 15. PMID:19369248 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA