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1mw9

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Revision as of 15:30, 12 October 2017

Crystal Structure of H365R mutant of 67 kDA N-terminal fragment of E. coli DNA Topoisomerase I

Structural highlights

1mw9 is a 1 chain structure with sequence from "bacillus_coli"_migula_1895 "bacillus coli" migula 1895. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Related:	1ecl, 1mw8
Gene:	TopA ("Bacillus coli" Migula 1895)
Activity:	DNA topoisomerase, with EC number 5.99.1.2
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[TOP1_ECOLI] 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.^[1] ^[2] ^[3]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

In order to gain insights into the mechaism of ssDNA binding and recognition by Escherichia coli DNA topoisomerase I, the structure of the 67 kDa N-terminal fragment of topoisomerase I was solved in complex with ssDNA. The structure reveals a new conformational stage in the multistep catalytic cycle of type IA topoisomerases. In the structure, the ssDNA binding groove leading to the active site is occupied, but the active site is not fully formed. Large conformational changes are not seen; instead, a single helix parallel to the ssDNA binding groove shifts to clamp the ssDNA. The structure helps clarify the temporal sequence of conformational events, starting from an initial empty enzyme and proceeding to a ssDNA-occupied and catalytically competent active site.

Structure of a complex between E. coli DNA topoisomerase I and single-stranded DNA.,Perry K, Mondragon A Structure. 2003 Nov;11(11):1349-58. PMID:14604525^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Chen SJ, Wang JC. Identification of active site residues in Escherichia coli DNA topoisomerase I. J Biol Chem. 1998 Mar 13;273(11):6050-6. PMID:9497321
↑ Zhu CX, Tse-Dinh YC. The acidic triad conserved in type IA DNA topoisomerases is required for binding of Mg(II) and subsequent conformational change. J Biol Chem. 2000 Feb 25;275(8):5318-22. PMID:10681504
↑ Zhang Z, Cheng B, Tse-Dinh YC. Crystal structure of a covalent intermediate in DNA cleavage and rejoining by Escherichia coli DNA topoisomerase I. Proc Natl Acad Sci U S A. 2011 Apr 26;108(17):6939-44. Epub 2011 Apr 11. PMID:21482796 doi:http://dx.doi.org/10.1073/pnas.1100300108
↑ Perry K, Mondragon A. Structure of a complex between E. coli DNA topoisomerase I and single-stranded DNA. Structure. 2003 Nov;11(11):1349-58. PMID:14604525

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1mw9"

@@ Line 1: / Line 1: @@
 ==Crystal Structure of H365R mutant of 67 kDA N-terminal fragment of E. coli DNA Topoisomerase I==
 <StructureSection load='1mw9' size='340' side='right' caption='[[1mw9]], [[Resolution|resolution]] 1.67&Aring;' scene=''>
@@ Line 7: / Line 8: @@
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">TopA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895])</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=1mw9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1mw9 OCA], [http://pdbe.org/1mw9 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1mw9 RCSB], [http://www.ebi.ac.uk/pdbsum/1mw9 PDBsum]</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=1mw9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1mw9 OCA], [http://pdbe.org/1mw9 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1mw9 RCSB], [http://www.ebi.ac.uk/pdbsum/1mw9 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1mw9 ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 19: / Line 20: @@
     <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/chain_selection.php?pdb_ID=2ata ConSurf].
+</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=1mw9 ConSurf].
 <div style="clear:both"></div>
 <div style="background-color:#fffaf0;">
@@ Line 30: / Line 31: @@
 </div>
 <div class="pdbe-citations 1mw9" style="background-color:#fffaf0;"></div>
-==See Also==
-*[[Topoisomerase|Topoisomerase]]
 == References ==
 <references/>

1mw9

From Proteopedia

Revision as of 15:30, 12 October 2017

Crystal Structure of H365R mutant of 67 kDA N-terminal fragment of E. coli DNA Topoisomerase I

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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