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5btl

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Revision as of 16:25, 15 November 2017

Crystal structure of a topoisomerase II complex

Structural highlights

5btl is a 8 chain structure with sequence from [1], Mycto and Myctu. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	,
NonStd Res:
Gene:	gyrA, Rv0006, MTCY10H4.04 (MYCTU), gyrB, MT0005 (MYCTO)
Activity:	DNA topoisomerase (ATP-hydrolyzing), with EC number 5.99.1.3
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[GYRA_MYCTU] DNA gyrase negatively supercoils closed circular double-stranded DNA in an ATP-dependent manner and also catalyzes the interconversion of other topological isomers of double-stranded DNA rings, including catenanes and knotted rings. [GYRB_MYCTO] A type II topoisomerase that negatively supercoils closed circular double-stranded (ds) DNA in an ATP-dependent manner to modulate DNA topology and maintain chromosomes in an underwound state. Negative supercoiling favors strand separation, and DNA replication, transcription, recombination and repair, all of which involve strand separation. Also able to catalyze the interconversion of other topological isomers of dsDNA rings, including catenanes and knotted rings. Type II topoisomerases break and join 2 DNA strands simultaneously in an ATP-dependent manner.[HAMAP-Rule:MF_01898]

Publication Abstract from PubMed

Mycobacterium tuberculosis (Mtb) infects one-third of the world's population and in 2013 accounted for 1.5 million deaths. Fluoroquinolone antibacterials, which target DNA gyrase, are critical agents used to halt the progression from multidrug-resistant tuberculosis to extensively resistant disease; however, fluoroquinolone resistance is emerging and new ways to bypass resistance are required. To better explain known differences in fluoroquinolone action, the crystal structures of the WT Mtb DNA gyrase cleavage core and a fluoroquinolone-sensitized mutant were determined in complex with DNA and five fluoroquinolones. The structures, ranging from 2.4- to 2.6-A resolution, show that the intrinsically low susceptibility of Mtb to fluoroquinolones correlates with a reduction in contacts to the water shell of an associated magnesium ion, which bridges fluoroquinolone-gyrase interactions. Surprisingly, the structural data revealed few differences in fluoroquinolone-enzyme contacts from drugs that have very different activities against Mtb. By contrast, a stability assay using purified components showed a clear relationship between ternary complex reversibility and inhibitory activities reported with cultured cells. Collectively, our data indicate that the stability of fluoroquinolone/DNA interactions is a major determinant of fluoroquinolone activity and that moieties that have been appended to the C7 position of different quinolone scaffolds do not take advantage of specific contacts that might be made with the enzyme. These concepts point to new approaches for developing quinolone-class compounds that have increased potency against Mtb and the ability to overcome resistance.

Crystal structure and stability of gyrase-fluoroquinolone cleaved complexes from Mycobacterium tuberculosis.,Blower TR, Williamson BH, Kerns RJ, Berger JM Proc Natl Acad Sci U S A. 2016 Feb 16;113(7):1706-13. doi:, 10.1073/pnas.1525047113. Epub 2016 Jan 20. PMID:26792525^[1]

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

References

↑ Blower TR, Williamson BH, Kerns RJ, Berger JM. Crystal structure and stability of gyrase-fluoroquinolone cleaved complexes from Mycobacterium tuberculosis. Proc Natl Acad Sci U S A. 2016 Feb 16;113(7):1706-13. doi:, 10.1073/pnas.1525047113. Epub 2016 Jan 20. PMID:26792525 doi:http://dx.doi.org/10.1073/pnas.1525047113

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5btl"

@@ Line 3: / Line 3: @@
 <StructureSection load='5btl' size='340' side='right' caption='[[5btl]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5btl]] is a 8 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5BTL OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5BTL FirstGlance]. <br>
+<table><tr><td colspan='2'>[[5btl]] is a 8 chain structure with sequence from [http://en.wikipedia.org/wiki/ ], [http://en.wikipedia.org/wiki/Mycto Mycto] and [http://en.wikipedia.org/wiki/Myctu Myctu]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5BTL OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5BTL FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=8MX:1-CYCLOPROPYL-6-FLUORO-8-METHYL-7-[(4AS,7AS)-OCTAHYDRO-6H-PYRROLO[3,4-B]PYRIDIN-6-YL]-4-OXO-1,4-DIHYDROQUINOLINE-3-CARBOXYLIC+ACID'>8MX</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>
 <tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=PTR:O-PHOSPHOTYROSINE'>PTR</scene></td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">gyrA, Rv0006, MTCY10H4.04 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83332 MYCTU]), gyrB, MT0005 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83331 MYCTO])</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_(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] </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=5btl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5btl OCA], [http://pdbe.org/5btl PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5btl RCSB], [http://www.ebi.ac.uk/pdbsum/5btl 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=5btl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5btl OCA], [http://pdbe.org/5btl PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5btl RCSB], [http://www.ebi.ac.uk/pdbsum/5btl PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5btl ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 24: / Line 25: @@
 __TOC__
 </StructureSection>
+[[Category: Mycto]]
+[[Category: Myctu]]
 [[Category: Berger, J M]]
 [[Category: Blower, T R]]

5btl

From Proteopedia

Revision as of 16:25, 15 November 2017

Crystal structure of a topoisomerase II complex

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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