View source for 2bm9


==cmcI-N160 in complex with SAM==
<StructureSection load='2bm9' size='340' side='right'caption='[[2bm9]], [[Resolution|resolution]] 2.94&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2bm9]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_clavuligerus Streptomyces clavuligerus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2BM9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2BM9 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.94&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SAM:S-ADENOSYLMETHIONINE'>SAM</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2bm9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2bm9 OCA], [https://pdbe.org/2bm9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2bm9 RCSB], [https://www.ebi.ac.uk/pdbsum/2bm9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2bm9 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/B5GLB3_STRCL B5GLB3_STRCL] Catalyzes the O-methylation of the hydroxyl group located on C-2 of the first rhamnosyl residue linked to the phenolic group of glycosylated phenolphthiocerol dimycocerosates (PGL) and p-hydroxybenzoic acid derivatives (p-HBAD).[ARBA:ARBA00003116]
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/bm/2bm9_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2bm9 ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Cephamycin C-producing microorganisms use two enzymes to convert cephalosporins to their 7alpha-methoxy derivatives. Here we report the X-ray structure of one of these enzymes, CmcI, from Streptomyces clavuligerus. The polypeptide chain of the enzyme folds into a C-terminal Rossmann domain and a smaller N-terminal domain, and the molecule packs as a hexamer in the crystal. The Rossmann domain binds S-adenosyl-L-methionine (SAM) and the demethylated product, S-adenosyl-L-homocysteine, in a fashion similar to the common binding mode of this cofactor in SAM-dependent methyltransferases. There is a magnesium-binding site in the vicinity of the SAM site with a bound magnesium ion ligated by residues Asp160, Glu186 and Asp187. The expected cephalosporin binding site near the magnesium ion is occupied by polyethyleneglycol (PEG) from the crystallisation medium. The geometry of the SAM and the magnesium binding sites is similar to that found in cathechol O-methyltransferase. The results suggest CmcI is a methyltransferase, and its most likely function is to catalyse the transfer of a methyl group from SAM to the 7alpha-hydroxy cephalosporin in the second catalytic reaction of cephamycin formation. Based on the docking of the putative substrate, 7alpha-hydroxy-O-carbamoyldeacetylcephalosporin C, to the structure of the ternary CmcI-Mg2+-SAM complex, we propose a model for substrate binding and catalysis. In this model, the 7-hydroxy group of the beta-lactam ring ligates the Mg2+ with its alpha-side facing the methyl group of SAM at a distance that would allow methylation of the hydroxyl-group.

Insights into cephamycin biosynthesis: the crystal structure of CmcI from Streptomyces clavuligerus.,Oster LM, Lester DR, Terwisscha van Scheltinga A, Svenda M, van Lun M, Genereux C, Andersson I J Mol Biol. 2006 Apr 28;358(2):546-58. Epub 2006 Feb 21. PMID:16527306<ref>PMID:16527306</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2bm9" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptomyces clavuligerus]]
[[Category: Andersson I]]
[[Category: Genereux C]]
[[Category: Lester DR]]
[[Category: Oster LM]]
[[Category: Svenda M]]
[[Category: Terwisscha Van Scheltinga A]]