View source for 1a41


==TYPE 1-TOPOISOMERASE CATALYTIC FRAGMENT FROM VACCINIA VIRUS==
<StructureSection load='1a41' size='340' side='right'caption='[[1a41]], [[Resolution|resolution]] 2.30&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1a41]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Vaccinia_virus Vaccinia virus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A41 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1A41 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]] 2.3&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><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=1a41 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1a41 OCA], [https://pdbe.org/1a41 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1a41 RCSB], [https://www.ebi.ac.uk/pdbsum/1a41 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1a41 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TOP1_VACCW TOP1_VACCW] Releases the supercoiling and torsional tension of DNA introduced during the DNA replication and transcription by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at the specific target site 5'-[CT]CCTTp site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(3'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 5'-OH DNA strand. The free DNA strand then undergoes passage around the unbroken strand thus removing DNA supercoils. Finally, in the religation step, the DNA 5'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone.<ref>PMID:16669621</ref> <ref>PMID:20187656</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/a4/1a41_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=1a41 ConSurf].
<div style="clear:both"></div>

==See Also==
*[[Topoisomerase 3D structures|Topoisomerase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Vaccinia virus]]
[[Category: Cheng C]]
[[Category: Kussie P]]
[[Category: Pavletich N]]
[[Category: Shuman S]]