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| ==Solution Structure of the MutT Pyrophosphohydrolase Complexed with Mg(2+) and 8-oxo-dGMP, a Tightly-bound Product== | | ==Solution Structure of the MutT Pyrophosphohydrolase Complexed with Mg(2+) and 8-oxo-dGMP, a Tightly-bound Product== |
| <StructureSection load='1puq' size='340' side='right'caption='[[1puq]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''> | | <StructureSection load='1puq' size='340' side='right'caption='[[1puq]]' scene=''> |
| == Structural highlights == | | == Structural highlights == |
| <table><tr><td colspan='2'>[[1puq]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PUQ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1PUQ FirstGlance]. <br> | | <table><tr><td colspan='2'>[[1puq]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PUQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1PUQ FirstGlance]. <br> |
| </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=8OG:8-OXO-2-DEOXY-GUANOSINE-5-MONOPHOSPHATE'>8OG</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr> | | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</td></tr> |
| <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1ppx|1ppx]], [[1mut|1mut]], [[1tum|1tum]], [[1pun|1pun]], [[1pus|1pus]]</td></tr> | | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=8OG:8-OXO-2-DEOXY-GUANOSINE-5-MONOPHOSPHATE'>8OG</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr> |
| <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">MUTT,STRAIN: K12-I7023 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895])</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=1puq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1puq OCA], [https://pdbe.org/1puq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1puq RCSB], [https://www.ebi.ac.uk/pdbsum/1puq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1puq ProSAT]</span></td></tr> |
| <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1puq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1puq OCA], [http://pdbe.org/1puq PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1puq RCSB], [http://www.ebi.ac.uk/pdbsum/1puq PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1puq ProSAT]</span></td></tr> | |
| </table> | | </table> |
| == Function == | | == Function == |
| [[http://www.uniprot.org/uniprot/MUTT_ECOLI MUTT_ECOLI]] Involved in the GO system responsible for removing an oxidatively damaged form of guanine (7,8-dihydro-8-oxoguanine) from DNA and the nucleotide pool. 8-oxo-dGTP is inserted opposite dA and dC residues of template DNA with almost equal efficiency thus leading to A.T to G.C transversions. MutT specifically degrades 8-oxo-dGTP to the monophosphate.<ref>PMID:1309939</ref> <ref>PMID:15850400</ref> | | [https://www.uniprot.org/uniprot/MUTT_ECOLI MUTT_ECOLI] Involved in the GO system responsible for removing an oxidatively damaged form of guanine (7,8-dihydro-8-oxoguanine) from DNA and the nucleotide pool. 8-oxo-dGTP is inserted opposite dA and dC residues of template DNA with almost equal efficiency thus leading to A.T to G.C transversions. MutT specifically degrades 8-oxo-dGTP to the monophosphate.<ref>PMID:1309939</ref> <ref>PMID:15850400</ref> |
| == Evolutionary Conservation == | | == Evolutionary Conservation == |
| [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
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| </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=1puq ConSurf]. | | </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=1puq ConSurf]. |
| <div style="clear:both"></div> | | <div style="clear:both"></div> |
| <div style="background-color:#fffaf0;">
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| == Publication Abstract from PubMed ==
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| To learn the structural basis for the unusually tight binding of 8-oxo-nucleotides to the MutT pyrophosphohydrolase of Escherichia coli (129 residues), the solution structure of the MutT-Mg(2+)-8-oxo-dGMP product complex (K(D) = 52 nM) was determined by standard 3-D heteronuclear NMR methods. Using 1746 NOEs (13.5 NOEs/residue) and 186 phi and psi values derived from backbone (15)N, Calpha, Halpha, and Cbeta chemical shifts, 20 converged structures were computed with NOE violations <or=0.25 A and total energies <or=450 kcal/mol. The pairwise root-mean-square deviations (RMSD) of backbone N, Calpha, and C' atoms for the secondary structured regions and for all residues of the 20 structures are 0.65 and 0.98 A, respectively, indicating a well-defined structure. Further refinement using residual dipolar coupling from 53 backbone N-H vectors slightly improved the RMSD values to 0.49 and 0.84 A, respectively. The secondary structures, which consisted of two alpha-helices and a five-stranded mixed beta-sheet, were indistinguishable from those of free MutT and of MutT in the quaternary MutT-Mg(2+)-(H(2)O)-AMPCPP-Mg(2+) complex. Comparisons of these three tertiary structures showed a narrowing of the hydrophobic nucleotide-binding cleft in the 8-oxo-dGMP complex resulting from a 2.5-4.5 A movement of helix I and a 1.5 A movement of helix II and loop 4 toward the cleft. The binding of 8-oxo-dGMP to MutT-Mg(2+) buries 71-78% of the surface area of the nucleotide. The 10(3.7)-fold weaker binding substrate analogue Mg(2+)-AMPCPP induced much smaller changes in tertiary structure, and MutT buried only 57% of the surface of the AMP moiety of AMPCPP. Formation of the MutT-Mg(2+)-8-oxo-dGMP complex slowed the backbone NH exchange rates of 45 residues of the enzyme by factors of 10(1)-10(6) as compared with the MutT-Mg(2+) and the MutT-Mg(2+)-dGMP complexes, suggesting a more compact structure when 8-oxo-dGMP is bound. The 10(4.6)-fold weaker binding of dGMP to MutT-Mg(2+) (K(D) = 1.8 mM) slowed the backbone exchange rates of only 20 residues and by smaller factors of approximately 10. Hence, the high affinity of MutT-Mg(2+) for 8-oxo-dGMP likely results from widespread ligand-induced conformation changes that narrow the nucleotide binding site and lower the overall free energy of the enzyme-product complex. Specific hydrogen bonding of the purine ring of 8-oxo-dGMP by the side chains of Asn-119 and Arg-78 may also contribute.
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| Solution structure and NH exchange studies of the MutT pyrophosphohydrolase complexed with Mg(2+) and 8-oxo-dGMP, a tightly bound product.,Massiah MA, Saraswat V, Azurmendi HF, Mildvan AS Biochemistry. 2003 Sep 2;42(34):10140-54. PMID:12939141<ref>PMID:12939141</ref>
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| From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| </div>
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| <div class="pdbe-citations 1puq" style="background-color:#fffaf0;"></div>
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| ==See Also== | | ==See Also== |
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| __TOC__ | | __TOC__ |
| </StructureSection> | | </StructureSection> |
| [[Category: Bacillus coli migula 1895]] | | [[Category: Escherichia coli]] |
| [[Category: Large Structures]] | | [[Category: Large Structures]] |
| [[Category: Azurmendi, H F]] | | [[Category: Azurmendi HF]] |
| [[Category: Massiah, M A]] | | [[Category: Massiah MA]] |
| [[Category: Mildvan, A S]] | | [[Category: Mildvan AS]] |
| [[Category: Saraswat, V]] | | [[Category: Saraswat V]] |
| [[Category: Hydrolase]]
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| [[Category: Mutator protein]]
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| [[Category: Mutt pyrophosphohydrolase-metal-product complex]]
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| [[Category: Nucleoside triphosphate pyrophosphohydrolase]]
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