2g67: Difference between revisions
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[[Image: | ==E. Coli Pyruvate Dehydrogenase E1 Component (Apoenzyme)== | ||
<StructureSection load='2g67' size='340' side='right' caption='[[2g67]], [[Resolution|resolution]] 2.32Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[2g67]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2G67 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2G67 FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1l8a|1l8a]], [[1rp7|1rp7]]</td></tr> | |||
<tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">aceE ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli])</td></tr> | |||
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Pyruvate_dehydrogenase_(acetyl-transferring) Pyruvate dehydrogenase (acetyl-transferring)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.2.4.1 1.2.4.1] </span></td></tr> | |||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2g67 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2g67 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2g67 RCSB], [http://www.ebi.ac.uk/pdbsum/2g67 PDBsum]</span></td></tr> | |||
<table> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/g6/2g67_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<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]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The first enzymatic component, E1 (EC 1.2.4.1), of the pyruvate dehydrogenase multienzyme complex (PDHc) utilizes thiamine diphosphate (ThDP) and Mg(2+) as cofactors. The structure of a branched-chain-specific E1 apoenzyme from the heterotetrameric alpha(2)beta(2) E1 family was recently reported and showed that disorder-to-order transformations in two active-site loops take place upon cofactor binding. To ascertain what effect the absence of cofactor may have in the homodimeric alpha(2) Escherichia coli PDHc E1, the corresponding apoenzyme has been prepared and its three-dimensional structure determined and analyzed at 2.32 A by crystallographic methods. This represents the first reported apoenzyme structure for any E1 component from the homodimeric alpha(2) family. Electron-density features occurring in the region where the cofactor pyrimidine ring would normally be expected to bind are of size, shape and location compatible with water molecules that form a hydrogen-bonded linkage between residues Glu571 and Val192, which normally make conserved interactions with the ThDP cofactor. A histidine side chain that normally forms hydrogen bonds to ThDP is disordered in its absence and partially occupies two sites. Unlike in the reported heterotetrameric branched-chain apo-E1, no disorder/order loop transformations are evident in apo-PDHc E1 relative to the holo-E1 enzyme (PDHc E1-ThDP-Mg(2+)). Differences in the extent of hydrogen-bonding networks found in the apo-E1 enzyme, the holo-E1 enzyme and in an inhibitor complex with bound thiamine 2-thiazolone diphosphate (ThTDP), PDHc E1-ThTDP-Mg(2+), are described. | |||
Active-site changes in the pyruvate dehydrogenase multienzyme complex E1 apoenzyme component from Escherichia coli observed at 2.32 A resolution.,Chandrasekhar K, Arjunan P, Sax M, Nemeria N, Jordan F, Furey W Acta Crystallogr D Biol Crystallogr. 2006 Nov;62(Pt 11):1382-6. Epub 2006, Oct 18. PMID:17057342<ref>PMID:17057342</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
*[[Pyruvate dehydrogenase|Pyruvate dehydrogenase]] | *[[Pyruvate dehydrogenase|Pyruvate dehydrogenase]] | ||
== References == | |||
== | <references/> | ||
< | __TOC__ | ||
</StructureSection> | |||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Arjunan, P.]] | [[Category: Arjunan, P.]] |
Revision as of 05:16, 29 September 2014
E. Coli Pyruvate Dehydrogenase E1 Component (Apoenzyme)E. Coli Pyruvate Dehydrogenase E1 Component (Apoenzyme)
Structural highlights
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 PubMedThe first enzymatic component, E1 (EC 1.2.4.1), of the pyruvate dehydrogenase multienzyme complex (PDHc) utilizes thiamine diphosphate (ThDP) and Mg(2+) as cofactors. The structure of a branched-chain-specific E1 apoenzyme from the heterotetrameric alpha(2)beta(2) E1 family was recently reported and showed that disorder-to-order transformations in two active-site loops take place upon cofactor binding. To ascertain what effect the absence of cofactor may have in the homodimeric alpha(2) Escherichia coli PDHc E1, the corresponding apoenzyme has been prepared and its three-dimensional structure determined and analyzed at 2.32 A by crystallographic methods. This represents the first reported apoenzyme structure for any E1 component from the homodimeric alpha(2) family. Electron-density features occurring in the region where the cofactor pyrimidine ring would normally be expected to bind are of size, shape and location compatible with water molecules that form a hydrogen-bonded linkage between residues Glu571 and Val192, which normally make conserved interactions with the ThDP cofactor. A histidine side chain that normally forms hydrogen bonds to ThDP is disordered in its absence and partially occupies two sites. Unlike in the reported heterotetrameric branched-chain apo-E1, no disorder/order loop transformations are evident in apo-PDHc E1 relative to the holo-E1 enzyme (PDHc E1-ThDP-Mg(2+)). Differences in the extent of hydrogen-bonding networks found in the apo-E1 enzyme, the holo-E1 enzyme and in an inhibitor complex with bound thiamine 2-thiazolone diphosphate (ThTDP), PDHc E1-ThTDP-Mg(2+), are described. Active-site changes in the pyruvate dehydrogenase multienzyme complex E1 apoenzyme component from Escherichia coli observed at 2.32 A resolution.,Chandrasekhar K, Arjunan P, Sax M, Nemeria N, Jordan F, Furey W Acta Crystallogr D Biol Crystallogr. 2006 Nov;62(Pt 11):1382-6. Epub 2006, Oct 18. PMID:17057342[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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