View source for 1kqj


==Crystal Structure of a Mutant of MutY Catalytic Domain==
<StructureSection load='1kqj' size='340' side='right'caption='[[1kqj]], [[Resolution|resolution]] 1.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1kqj]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KQJ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1KQJ 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]] 1.7&#8491;</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=SO4:SULFATE+ION'>SO4</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=1kqj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1kqj OCA], [https://pdbe.org/1kqj PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1kqj RCSB], [https://www.ebi.ac.uk/pdbsum/1kqj PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1kqj ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MUTY_ECOLI MUTY_ECOLI] Adenine glycosylase active on G-A mispairs. MutY also corrects error-prone DNA synthesis past GO lesions which are due to the oxidatively damaged form of guanine: 7,8-dihydro-8-oxoguanine (8-oxo-dGTP).
== 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/kq/1kqj_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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=1kqj ConSurf].
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== Publication Abstract from PubMed ==
The Escherichia coli DNA repair enzyme MutY plays an important role in the recognition and repair of 7,8-dihydro-8-oxo-2'-deoxyguanosine-2'-deoxyadenosine (OG*A) mismatches in DNA. MutY prevents DNA mutations caused by the misincorporation of A opposite OG by catalyzing the deglycosylation of the aberrant adenine. MutY is representative of a unique subfamily of DNA repair enzymes that also contain a [4Fe-4S]2+ cluster, which has been implicated in substrate recognition. Previously, we have used site-directed mutagenesis to individually replace the cysteine ligands to the [4Fe-4S]2+ cluster of E. coli MutY with serine, histidine, or alanine. These experiments suggested that histidine coordination to the iron-sulfur cluster may be accommodated in MutY at position 199. Purification and enzymatic analysis of C199H and C199S forms indicated that these forms behave nearly identical to the WT enzyme. Furthermore, introduction of the C199H mutation in a truncated form of MutY (C199HT) allowed for crystallization and structural characterization of the modified [4Fe-4S] cluster coordination. The C199HT structure showed that histidine coordinated to the iron cluster although comparison to the structure of the WT truncated enzyme indicated that the occupancy of iron at the modified position had been reduced to 60%. Electron paramagnetic resonance (EPR) spectroscopy on samples of C199HT indicates that a significant percentage (15-30%) of iron clusters were of the [3Fe-4S]1+ form. Oxidation of the C199HT enzyme with ferricyanide increases the amount of the 3Fe cluster by approximately 2-fold. Detailed kinetic analysis on samples containing a mixture of [3Fe-4S]1+ and [4Fe-4S]2+ forms indicated that the reactivity of the [3Fe-4S]1+ C199HT enzyme does not differ significantly from that of the WT truncated enzyme. The relative resistance of the [4Fe-4S]2+ cluster toward oxidation, as well as the retention of activity of the [3Fe-4S]1+ form, may be an important aspect of the role of MutY in repair of DNA damage resulting from oxidative stress.

Noncysteinyl coordination to the [4Fe-4S]2+ cluster of the DNA repair adenine glycosylase MutY introduced via site-directed mutagenesis. Structural characterization of an unusual histidinyl-coordinated cluster.,Messick TE, Chmiel NH, Golinelli MP, Langer MR, Joshua-Tor L, David SS Biochemistry. 2002 Mar 26;41(12):3931-42. PMID:11900536<ref>PMID:11900536</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1kqj" style="background-color:#fffaf0;"></div>

==See Also==
*[[DNA glycosylase 3D structures|DNA glycosylase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Chmiel NH]]
[[Category: David SS]]
[[Category: Golinelli MP]]
[[Category: Joshua-Tor L]]
[[Category: Messick TE]]