View source for 2ybq


==The x-ray structure of the SAM-dependent uroporphyrinogen III methyltransferase NirE from Pseudomonas aeruginosa in complex with SAH and uroporphyrinogen III==
<StructureSection load='2ybq' size='340' side='right'caption='[[2ybq]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2ybq]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Pseudomonas_aeruginosa_PAO1 Pseudomonas aeruginosa PAO1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2YBQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2YBQ 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&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SAH:S-ADENOSYL-L-HOMOCYSTEINE'>SAH</scene>, <scene name='pdbligand=UP2:UROPORPHYRINOGEN+III'>UP2</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=2ybq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ybq OCA], [https://pdbe.org/2ybq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ybq RCSB], [https://www.ebi.ac.uk/pdbsum/2ybq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ybq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/P95417_PSEAI P95417_PSEAI] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
During the biosynthesis of heme d(1), the essential cofactor of cytochrome cd(1) nitrite reductase, the NirE protein catalyzes the methylation of uroporphyrinogen III to precorrin-2 using S-adenosyl-L-methionine (SAM) as the methyl group donor. The crystal structure of Pseudomonas aeruginosa NirE in complex with its substrate uroporphyrinogen III and the reaction by-product S-adenosyl-L-homocysteine (SAH) was solved to 2.0 A resolution. This represents the first enzyme-substrate complex structure for a SAM-dependent uroporphyrinogen III methyltransferase. The large substrate binds on top of the SAH in a "puckered" conformation in which the two pyrrole rings facing each other point into the same direction either upward or downward. Three arginine residues, a histidine, and a methionine are involved in the coordination of uroporphyrinogen III. Through site-directed mutagenesis of the nirE gene and biochemical characterization of the corresponding NirE variants the amino acid residues Arg-111, Glu-114, and Arg-149 were identified to be involved in NirE catalysis. Based on our structural and biochemical findings, we propose a potential catalytic mechanism for NirE in which the methyl transfer reaction is initiated by an arginine catalyzed proton abstraction from the C-20 position of the substrate.

Crystal structure of the heme d1 biosynthesis enzyme NirE in complex with its substrate reveals new insights into the catalytic mechanism of S-adenosyl-L-methionine-dependent uroporphyrinogen III methyltransferases.,Storbeck S, Saha S, Krausze J, Klink BU, Heinz DW, Layer G J Biol Chem. 2011 Jul 29;286(30):26754-67. Epub 2011 May 31. PMID:21632530<ref>PMID:21632530</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2ybq" style="background-color:#fffaf0;"></div>

==See Also==
*[[SAM-dependent methyltrasferase 3D structures|SAM-dependent methyltrasferase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Pseudomonas aeruginosa PAO1]]
[[Category: Heinz DW]]
[[Category: Klink BU]]
[[Category: Krausze J]]
[[Category: Layer G]]
[[Category: Saha S]]
[[Category: Storbeck S]]