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1pvn
From Proteopedia
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| - | [[Image:1pvn.jpg|left|200px]] | ||
| - | + | ==The crystal structure of the complex between IMP dehydrogenase catalytic domain and a transition state analogue MZP== | |
| - | + | <StructureSection load='1pvn' size='340' side='right'caption='[[1pvn]], [[Resolution|resolution]] 2.00Å' scene=''> | |
| - | + | == Structural highlights == | |
| - | | | + | <table><tr><td colspan='2'>[[1pvn]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Tritrichomonas_suis Tritrichomonas suis]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1mwf 1mwf]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PVN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1PVN 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]] 2Å</td></tr> | |
| - | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=MZP:4-CARBAMOYL-1-BETA-D-RIBOFURANOSYL-IMIDAZOLIUM-5-OLATE-5-PHOSPHATE'>MZP</scene>, <scene name='pdbligand=TRS:2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>TRS</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=1pvn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1pvn OCA], [https://pdbe.org/1pvn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1pvn RCSB], [https://www.ebi.ac.uk/pdbsum/1pvn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1pvn ProSAT]</span></td></tr> | |
| - | + | </table> | |
| - | + | == Function == | |
| - | + | [https://www.uniprot.org/uniprot/IMDH_TRIFO IMDH_TRIFO] Catalyzes the conversion of inosine 5'-phosphate (IMP) to xanthosine 5'-phosphate (XMP), the first committed and rate-limiting step in the de novo synthesis of guanine nucleotides, and therefore plays an important role in the regulation of cell growth. Could also have a single-stranded nucleic acid-binding activity and could play a role in RNA and/or DNA metabolism.<ref>PMID:10029522</ref> | |
| - | + | == 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/pv/1pvn_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=1pvn ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
Mizoribine monophosphate (MZP) is the active metabolite of the immunosuppressive agent mizoribine and a potent inhibitor of IMP dehydrogenase (IMPDH). This enzyme catalyzes the oxidation of IMP to XMP with the concomitant reduction of NAD via a covalent intermediate at Cys319 (E-XMP). Surprisingly, mutational analysis indicates that MZP is a transition state analogue although its structure does not resemble that of the expected transition state. Here we report the X-ray crystal structure of the E.MZP complex at 2.0 A resolution that reveals a transition state-like structure and solves the mechanistic puzzle of the IMPDH reaction. The protein assumes a new conformation where a flap folds into the NAD site and MZP, Cys319, and a water molecule are arranged in a geometry resembling the transition state. The water appears to be activated by interactions with a conserved Arg418-Tyr419 dyad. Mutagenesis experiments confirm that this new closed conformation is required for the hydrolysis of E-XMP, but not for the reduction of NAD. The closed conformation provides a structural explanation for the differences in drug selectivity and catalytic efficiency of IMPDH isozymes. | Mizoribine monophosphate (MZP) is the active metabolite of the immunosuppressive agent mizoribine and a potent inhibitor of IMP dehydrogenase (IMPDH). This enzyme catalyzes the oxidation of IMP to XMP with the concomitant reduction of NAD via a covalent intermediate at Cys319 (E-XMP). Surprisingly, mutational analysis indicates that MZP is a transition state analogue although its structure does not resemble that of the expected transition state. Here we report the X-ray crystal structure of the E.MZP complex at 2.0 A resolution that reveals a transition state-like structure and solves the mechanistic puzzle of the IMPDH reaction. The protein assumes a new conformation where a flap folds into the NAD site and MZP, Cys319, and a water molecule are arranged in a geometry resembling the transition state. The water appears to be activated by interactions with a conserved Arg418-Tyr419 dyad. Mutagenesis experiments confirm that this new closed conformation is required for the hydrolysis of E-XMP, but not for the reduction of NAD. The closed conformation provides a structural explanation for the differences in drug selectivity and catalytic efficiency of IMPDH isozymes. | ||
| - | + | The immunosuppressive agent mizoribine monophosphate forms a transition state analogue complex with inosine monophosphate dehydrogenase.,Gan L, Seyedsayamdost MR, Shuto S, Matsuda A, Petsko GA, Hedstrom L Biochemistry. 2003 Feb 4;42(4):857-63. PMID:12549902<ref>PMID:12549902</ref> | |
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| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | <div class="pdbe-citations 1pvn" style="background-color:#fffaf0;"></div> | |
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| - | + | ==See Also== | |
| + | *[[Inosine monophosphate dehydrogenase 3D structures|Inosine monophosphate dehydrogenase 3D structures]] | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Tritrichomonas suis]] | ||
| + | [[Category: Gan L]] | ||
| + | [[Category: Hedstrom L]] | ||
| + | [[Category: Matsuda A]] | ||
| + | [[Category: Petsko GA]] | ||
| + | [[Category: Seyedsayamdost M]] | ||
| + | [[Category: Shuto S]] | ||
Current revision
The crystal structure of the complex between IMP dehydrogenase catalytic domain and a transition state analogue MZP
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