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1cy8

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Revision as of 15:49, 15 February 2015

COMPLEX OF E.COLI DNA TOPOISOMERASE I WITH 5'-THYMIDINE MONOPHOSPHATE AND 3'-THYMIDINE MONOPHOSPHATE

Structural highlights

1cy8 is a 1 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, ,
Related:	1cy0, 1cy1, 1cy4, 1cy2, 1cy7, 1cy6, 1cy9, 1cyy
Activity:	DNA topoisomerase, with EC number 5.99.1.2
Resources:	FirstGlance, OCA, RCSB, PDBsum

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

DNA topoisomerases are the enzymes responsible for controlling and maintaining the topological states of DNA. Type IA enzymes work by transiently breaking the phosphodiester backbone of one strand to allow passage of another strand through the break. The protein has to perform complex rearrangements of the DNA, and hence it is likely that different regions of the enzyme bind DNA with different affinities. In order to identify some of the DNA binding sites in the protein, we have solved the structures of several complexes of the 67 kDa N-terminal fragment of Escherichia coli DNA topoisomerase I with mono- and trinucleotides. There are five different binding sites in the complexes, one of which is adjacent to the active site. Two other sites are in the central hole of the protein and may represent general DNA binding regions. The positions of these sites allow us to identify different DNA binding regions and to understand their possible roles in the catalytic cycle.

Protein-nucleotide interactions in E. coli DNA topoisomerase I.,Feinberg H, Changela A, Mondragon A Nat Struct Biol. 1999 Oct;6(10):961-8. PMID:10504732^[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
↑ Feinberg H, Changela A, Mondragon A. Protein-nucleotide interactions in E. coli DNA topoisomerase I. Nat Struct Biol. 1999 Oct;6(10):961-8. PMID:10504732 doi:http://dx.doi.org/10.1038/13333

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1cy8"

@@ Line 8: / Line 8: @@
 <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=1cy8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1cy8 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1cy8 RCSB], [http://www.ebi.ac.uk/pdbsum/1cy8 PDBsum]</span></td></tr>
 </table>
+== Function ==
+[[http://www.uniprot.org/uniprot/TOP1_ECOLI 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.<ref>PMID:9497321</ref> <ref>PMID:10681504</ref> <ref>PMID:21482796</ref>
 == Evolutionary Conservation ==
 [[Image:Consurf_key_small.gif|200px|right]]

1cy8

From Proteopedia

Revision as of 15:49, 15 February 2015

COMPLEX OF E.COLI DNA TOPOISOMERASE I WITH 5'-THYMIDINE MONOPHOSPHATE AND 3'-THYMIDINE MONOPHOSPHATE

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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