3px7

<StructureSection load='3px7' size='340' side='right' caption='[[3px7]], [[Resolution|resolution]] 2.30&Aring;' scene=''>

<table><tr><td colspan='2'>[[3px7]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Ecod1 Ecod1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3PX7 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3PX7 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1ecl|1ecl]], [[1cy0|1cy0]], [[1cy4|1cy4]]</td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">415337, EcDH1_2375 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=536056 ECOD1])</td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/DNA_topoisomerase DNA topoisomerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.99.1.2 5.99.1.2] </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=3px7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3px7 OCA], [http://pdbe.org/3px7 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3px7 RCSB], [http://www.ebi.ac.uk/pdbsum/3px7 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3px7 ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/C9QXS7_ECOD1 C9QXS7_ECOD1]] Releases the supercoiling and torsional tension of DNA, which is 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 a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(5'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 3'-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 3'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone.[HAMAP-Rule:MF_00952][SAAS:SAAS00003469]