View source for 3lwl


==Structure of Klenow fragment of Taq polymerase in complex with an abasic site==
<StructureSection load='3lwl' size='340' side='right'caption='[[3lwl]], [[Resolution|resolution]] 2.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3lwl]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermus_aquaticus Thermus aquaticus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3LWL OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3LWL 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]] 2.25&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=2DA:2,3-DIDEOXYADENOSINE-5-MONOPHOSPHATE'>2DA</scene>, <scene name='pdbligand=3DR:1,2-DIDEOXYRIBOFURANOSE-5-PHOSPHATE'>3DR</scene>, <scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=DDS:2,3-DIDEOXYADENOSINE+TRIPHOSPHATE'>DDS</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=3lwl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3lwl OCA], [https://pdbe.org/3lwl PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3lwl RCSB], [https://www.ebi.ac.uk/pdbsum/3lwl PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3lwl ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DPO1_THEAQ DPO1_THEAQ] 
== 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/lw/3lwl_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=3lwl ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Abasic sites represent the most frequent DNA lesions in the genome that have high mutagenic potential and lead to mutations commonly found in human cancers. Although these lesions are devoid of the genetic information, adenine is most efficiently inserted when abasic sites are bypassed by DNA polymerases, a phenomenon termed A-rule. In this study, we present X-ray structures of a DNA polymerase caught while incorporating a nucleotide opposite an abasic site. We found that a functionally important tyrosine side chain directs for nucleotide incorporation rather than DNA. It fills the vacant space of the absent template nucleobase and thereby mimics a pyrimidine nucleobase directing for preferential purine incorporation opposite abasic residues because of enhanced geometric fit to the active site. This amino acid templating mechanism was corroborated by switching to pyrimidine specificity because of mutation of the templating tyrosine into tryptophan. The tyrosine is located in motif B and highly conserved throughout evolution from bacteria to humans indicating a general amino acid templating mechanism for bypass of non-instructive lesions by DNA polymerases at least from this sequence family.

Replication through an abasic DNA lesion: structural basis for adenine selectivity.,Obeid S, Blatter N, Kranaster R, Schnur A, Diederichs K, Welte W, Marx A EMBO J. 2010 May 19;29(10):1738-47. Epub 2010 Apr 16. PMID:20400942<ref>PMID:20400942</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3lwl" style="background-color:#fffaf0;"></div>

==See Also==
*[[DNA polymerase 3D structures|DNA polymerase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Thermus aquaticus]]
[[Category: Diederichs K]]
[[Category: Marx A]]
[[Category: Obeid S]]