1u1h

<table><tr><td colspan='2'>[[1u1h]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Arath Arath]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1U1H OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=1U1H FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MET:METHIONINE'>MET</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>

<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">CIMS ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=3702 ARATH])</td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/5-methyltetrahydropteroyltriglutamate--homocysteine_S-methyltransferase 5-methyltetrahydropteroyltriglutamate--homocysteine S-methyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.1.14 2.1.1.14] </span></td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=1u1h FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1u1h OCA], [http://pdbe.org/1u1h PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1u1h RCSB], [http://www.ebi.ac.uk/pdbsum/1u1h PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1u1h ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/METE_ARATH METE_ARATH]] Catalyzes the transfer of a methyl group from 5-methyltetrahydrofolate to homocysteine resulting in methionine formation.

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== Publication Abstract from PubMed ==

Cobalamin-independent methionine synthase (MetE) catalyzes the synthesis of methionine by a direct transfer of the methyl group of N5-methyltetrahydrofolate (CH3-H2PteGlun) to the sulfur atom of homocysteine (Hcy). We report here the first crystal structure of this metalloenzyme under different forms, free or complexed with the Hcy and folate substrates. The Arabidopsis thaliana MetE (AtMetE) crystals reveal a monomeric structure built by two (betaalpha)8 barrels making a deep groove at their interface. The active site is located at the surface of the C-terminal domain, facing the large interdomain cleft. Inside the active site, His647, Cys649, and Cys733 are involved in zinc coordination, whereas Asp605, Ile437, and Ser439 interact with Hcy. Opposite the zinc/Hcy binding site, a cationic loop (residues 507-529) belonging to the C-terminal domain anchors the first glutamyl residue of CH3-H4PteGlu5. The pterin moiety of CH3-H4PteGlu5 is stacked with Trp567, enabling the N5-methyl group to protrude in the direction of the zinc atom. These data suggest a structural role of the N-terminal domain of AtMetE in the stabilization of loop 507-529 and in the interaction with the poly-glutamate chain of CH3-H4PteGlun. Comparison of AtMetE structures reveals that the addition of Hcy does not lead to a direct coordination of the sulfur atom with zinc but to a reorganization of the zinc binding site with a stronger coordination to Cys649, Cys733, and a water molecule.

 

<div class="pdbe-citations 1u1h" style="background-color:#fffaf0;"></div>

[[Category: 5-methyltetrahydropteroyltriglutamate--homocysteine S-methyltransferase]]

[[Category: Arath]]

[[Category: Dumas, R]]

[[Category: Ferrer, J L]]

[[Category: Ravanel, S]]

[[Category: Robert, M]]

[[Category: Transferase]]