View source for 1qqc


==CRYSTAL STRUCTURE OF AN ARCHAEBACTERIAL DNA POLYMERASE D.TOK==
<StructureSection load='1qqc' size='340' side='right'caption='[[1qqc]], [[Resolution|resolution]] 2.60&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1qqc]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Desulfurococcus_sp._Tok Desulfurococcus sp. Tok]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QQC OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1QQC 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]] 2.6&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=1qqc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qqc OCA], [https://pdbe.org/1qqc PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1qqc RCSB], [https://www.ebi.ac.uk/pdbsum/1qqc PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1qqc ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DPOL_DESST DPOL_DESST] Thermostable DNA polymerase. In addition to polymerase activity, this DNA polymerase exhibits 3' to 5' exonuclease activity.<ref>PMID:8663453</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/qq/1qqc_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=1qqc ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
BACKGROUND: Members of the Pol II family of DNA polymerases are responsible for chromosomal replication in eukaryotes, and carry out highly processive DNA replication when attached to ring-shaped processivity clamps. The sequences of Pol II polymerases are distinct from those of members of the well-studied Pol I family of DNA polymerases. The DNA polymerase from the archaebacterium Desulfurococcus strain Tok (D. Tok Pol) is a member of the Pol II family that retains catalytic activity at elevated temperatures. RESULTS: The crystal structure of D. Tok Pol has been determined at 2.4 A resolution. The architecture of this Pol II type DNA polymerase resembles that of the DNA polymerase from the bacteriophage RB69, with which it shares less than approximately 20% sequence identity. As in RB69, the central catalytic region of the DNA polymerase is located within the 'palm' subdomain and is strikingly similar in structure to the corresponding regions of Pol I type DNA polymerases. The structural scaffold that surrounds the catalytic core in D. Tok Pol is unrelated in structure to that of Pol I type polymerases. The 3'-5' proofreading exonuclease domain of D. Tok Pol resembles the corresponding domains of RB69 Pol and Pol I type DNA polymerases. The exonuclease domain in D. Tok Pol is located in the same position relative to the polymerase domain as seen in RB69, and on the opposite side of the palm subdomain compared to its location in Pol I type polymerases. The N-terminal domain of D. Tok Pol has structural similarity to RNA-binding domains. Sequence alignments suggest that this domain is conserved in the eukaryotic DNA polymerases delta and epsilon. CONCLUSIONS: The structure of D. Tok Pol confirms that the modes of binding of the template and extrusion of newly synthesized duplex DNA are likely to be similar in both Pol II and Pol I type DNA polymerases. However, the mechanism by which the newly synthesized product transits in and out of the proofreading exonuclease domain has to be quite different. The discovery of a domain that seems to be an RNA-binding module raises the possibility that Pol II family members interact with RNA.

Crystal structure of an archaebacterial DNA polymerase.,Zhao Y, Jeruzalmi D, Moarefi I, Leighton L, Lasken R, Kuriyan J Structure. 1999 Oct 15;7(10):1189-99. PMID:10545321<ref>PMID:10545321</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 1qqc" style="background-color:#fffaf0;"></div>

==See Also==
*[[DNA polymerase 3D structures|DNA polymerase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Desulfurococcus sp. Tok]]
[[Category: Large Structures]]
[[Category: Jeruzalmi D]]
[[Category: Kuriyan J]]
[[Category: Lasken R]]
[[Category: Leighton L]]
[[Category: Zhao Y]]