1mx0
From Proteopedia
(New page: 200px<br /><applet load="1mx0" size="450" color="white" frame="true" align="right" spinBox="true" caption="1mx0, resolution 2.300Å" /> '''Structure of topois...) |
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| - | [[Image:1mx0.gif|left|200px]]<br /><applet load="1mx0" size=" | + | [[Image:1mx0.gif|left|200px]]<br /><applet load="1mx0" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1mx0, resolution 2.300Å" /> | caption="1mx0, resolution 2.300Å" /> | ||
'''Structure of topoisomerase subunit'''<br /> | '''Structure of topoisomerase subunit'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Type IIA and type IIB topoisomerases each possess the ability to pass one | + | Type IIA and type IIB topoisomerases each possess the ability to pass one DNA duplex through another in an ATP-dependent manner. The role of ATP in the strand passage reaction is poorly understood, particularly for the type IIB (topoisomerase VI) family. We have solved the structure of the ATP-binding subunit of topoisomerase VI (topoVI-B) in two states: an unliganded monomer and a nucleotide-bound dimer. We find that topoVI-B is highly structurally homologous to the entire 40-43 kDa ATPase region of type IIA topoisomerases and MutL proteins. Nucleotide binding to topoVI-B leads to dimerization of the protein and causes dramatic conformational changes within each protomer. Our data demonstrate that type IIA and type IIB topoisomerases have descended from a common ancestor and reveal how ATP turnover generates structural signals in the reactions of both type II topoisomerase families. When combined with the structure of the A subunit to create a picture of the intact topoisomerase VI holoenzyme, the ATP-driven motions of topoVI-B reveal a simple mechanism for strand passage by the type IIB topoisomerases. |
==About this Structure== | ==About this Structure== | ||
| - | 1MX0 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Sulfolobus_shibatae Sulfolobus shibatae] with MG, NA and ANP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA_topoisomerase_(ATP-hydrolyzing) DNA topoisomerase (ATP-hydrolyzing)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.99.1.3 5.99.1.3] Full crystallographic information is available from [http:// | + | 1MX0 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Sulfolobus_shibatae Sulfolobus shibatae] with <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=NA:'>NA</scene> and <scene name='pdbligand=ANP:'>ANP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA_topoisomerase_(ATP-hydrolyzing) DNA topoisomerase (ATP-hydrolyzing)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.99.1.3 5.99.1.3] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1MX0 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Sulfolobus shibatae]] | [[Category: Sulfolobus shibatae]] | ||
| - | [[Category: Berger, J | + | [[Category: Berger, J M.]] |
| - | [[Category: Corbett, K | + | [[Category: Corbett, K D.]] |
[[Category: ANP]] | [[Category: ANP]] | ||
[[Category: MG]] | [[Category: MG]] | ||
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[[Category: topoisomerase]] | [[Category: topoisomerase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:00:06 2008'' |
Revision as of 12:00, 21 February 2008
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Structure of topoisomerase subunit
Overview
Type IIA and type IIB topoisomerases each possess the ability to pass one DNA duplex through another in an ATP-dependent manner. The role of ATP in the strand passage reaction is poorly understood, particularly for the type IIB (topoisomerase VI) family. We have solved the structure of the ATP-binding subunit of topoisomerase VI (topoVI-B) in two states: an unliganded monomer and a nucleotide-bound dimer. We find that topoVI-B is highly structurally homologous to the entire 40-43 kDa ATPase region of type IIA topoisomerases and MutL proteins. Nucleotide binding to topoVI-B leads to dimerization of the protein and causes dramatic conformational changes within each protomer. Our data demonstrate that type IIA and type IIB topoisomerases have descended from a common ancestor and reveal how ATP turnover generates structural signals in the reactions of both type II topoisomerase families. When combined with the structure of the A subunit to create a picture of the intact topoisomerase VI holoenzyme, the ATP-driven motions of topoVI-B reveal a simple mechanism for strand passage by the type IIB topoisomerases.
About this Structure
1MX0 is a Single protein structure of sequence from Sulfolobus shibatae with , and as ligands. Active as DNA topoisomerase (ATP-hydrolyzing), with EC number 5.99.1.3 Full crystallographic information is available from OCA.
Reference
Structure of the topoisomerase VI-B subunit: implications for type II topoisomerase mechanism and evolution., Corbett KD, Berger JM, EMBO J. 2003 Jan 2;22(1):151-63. PMID:12505993
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