View source for 6cig


==CRYSTAL STRUCTURE ANALYSIS OF SELENOMETHIONINE SUBSTITUTED ISOFLAVONE O-METHYLTRANSFERASE==
<StructureSection load='6cig' size='340' side='right'caption='[[6cig]], [[Resolution|resolution]] 1.65&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6cig]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Alfalfa Alfalfa]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1fpx 1fpx]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6CIG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6CIG FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=PG4:TETRAETHYLENE+GLYCOL'>PG4</scene>, <scene name='pdbligand=SAH:S-ADENOSYL-L-HOMOCYSTEINE'>SAH</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=T3A:N-(TRIS(HYDROXYMETHYL)METHYL)-3-AMINOPROPANESULFONIC+ACID'>T3A</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=CSX:S-OXY+CYSTEINE'>CSX</scene>, <scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Isoflavone_7-O-methyltransferase Isoflavone 7-O-methyltransferase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.1.150 2.1.1.150] </span></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=6cig FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6cig OCA], [https://pdbe.org/6cig PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6cig RCSB], [https://www.ebi.ac.uk/pdbsum/6cig PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6cig ProSAT]</span></td></tr>
</table>
== Function ==
[[https://www.uniprot.org/uniprot/7OMT8_MEDSA 7OMT8_MEDSA]] Transfers a methyl group to 7-hydroxyls of the isoflavones daidzein, genistein and 6,7,4'-trihydroxyisoflavone. Can also methylate (+)6a-hydroxymaackiain with lower efficiency. 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Chalcone O-methyltransferase (ChOMT) and isoflavone O-methyltransferase (IOMT) are S-adenosyl-l-methionine (SAM) dependent plant natural product methyltransferases involved in secondary metabolism in Medicago sativa (alfalfa). Here we report the crystal structure of ChOMT in complex with the product S-adenosyl-l-homocysteine and the substrate isoliquiritigenin (4,2',4'-trihydroxychalcone) refined to 1.8 A as well as the crystal structure of IOMT in complex with the products S-adenosyl-l-homocysteine and isoformononetin (4'-hydroxy-7-methoxyisoflavone) refined to 1.4 A. These two OMTs constitute the first plant methyltransferases to be structurally characterized and reveal a novel oligomerization domain and the molecular determinants for substrate selection. As such, this work provides a structural basis for understanding the substrate specificity of the diverse family of plant OMTs and facilitates the engineering of novel activities in this extensive class of natural product biosynthetic enzymes.

Structures of two natural product methyltransferases reveal the basis for substrate specificity in plant O-methyltransferases.,Zubieta C, He XZ, Dixon RA, Noel JP Nat Struct Biol. 2001 Mar;8(3):271-9. PMID:11224575<ref>PMID:11224575</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6cig" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Alfalfa]]
[[Category: Isoflavone 7-O-methyltransferase]]
[[Category: Large Structures]]
[[Category: Dixon, R A]]
[[Category: Kowiel, M]]
[[Category: Noel, J P]]
[[Category: Porebski, P J]]
[[Category: Shabalin, I G]]
[[Category: Zubieta, C]]
[[Category: S-adenosyl-l-homocysteine complex]]
[[Category: Selenomethionine]]
[[Category: Transferase]]