1i4x: Difference between revisions
New page: left|200px<br /> <applet load="1i4x" size="450" color="white" frame="true" align="right" spinBox="true" caption="1i4x, resolution 2.4Å" /> '''STAPHYLOCOCCAL ENTER... |
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== | ==STAPHYLOCOCCAL ENTEROTOXIN C2, MONOCLINIC FORM CRYSTALLIZED AT PH 8.0== | ||
The three-dimensional structure of staphylococcal enterotoxin C2 (SEC2), a | <StructureSection load='1i4x' size='340' side='right'caption='[[1i4x]], [[Resolution|resolution]] 2.40Å' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1i4x]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Staphylococcus_aureus Staphylococcus aureus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1I4X OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1I4X FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.4Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1i4x FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1i4x OCA], [https://pdbe.org/1i4x PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1i4x RCSB], [https://www.ebi.ac.uk/pdbsum/1i4x PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1i4x ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/ENTC2_STAAU ENTC2_STAAU] Staphylococcal enterotoxins cause the intoxication staphylococcal food poisoning syndrome. The illness characterized by high fever, hypotension, diarrhea, shock, and in some cases death. | |||
== 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/i4/1i4x_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/main_output.php?pdb_ID=1i4x ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The three-dimensional structure of staphylococcal enterotoxin C2 (SEC2), a toxin as well as a superantigen, has been determined at various pH levels from two different crystal forms, tetragonal (pH 5.0, 5.5, 6.0 and 6.5) and monoclinic (pH 8.0) at 100 and 293 K, respectively, by the molecular-replacement method. Tetragonal crystals belong to space group P4(3)2(1)2, with unit-cell parameters a = b = 42.68, c = 289.15 A (at pH 5.0), and monoclinic crystals to space group P2(1), with unit-cell parameters a = 43.3, b = 70.6, c = 42.2 A, beta = 90.3 degrees. SEC2 contains a zinc-binding motif, D+HExxH, and accordingly a Zn atom has been identified. The coordination of the zinc ion suggests that it may be catalytic zinc rather than structural, but there is so far no biological evidence that it possesses catalytic activity. However, superantigen staphylococcal exfoliative toxins A and B have been shown to have enzymatic activity after their fold was identified to be similar to that of serine protease. The structure and its conformation are similar to the previously reported structures of SEC2. Though it was expected that the zinc ion may be leached out, as the histidines coordinating the zinc ion are expected to be protonated below pH 6.0, zinc is present at all pH values. The coordination distances to zinc increase with decreasing pH, with the distances being the least at pH 8.0. The results of automated model building using the ARP/wARP program for different data sets collected at various pH values are discussed. | |||
Structure of staphylococcal enterotoxin C2 at various pH levels.,Kumaran D, Eswaramoorthy S, Furey W, Sax M, Swaminathan S Acta Crystallogr D Biol Crystallogr. 2001 Sep;57(Pt 9):1270-5. Epub 2001, Aug 23. PMID:11526318<ref>PMID:11526318</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
[[Category: | <div class="pdbe-citations 1i4x" style="background-color:#fffaf0;"></div> | ||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Large Structures]] | |||
[[Category: Staphylococcus aureus]] | [[Category: Staphylococcus aureus]] | ||
[[Category: Sax | [[Category: Sax M]] | ||
[[Category: Swaminathan | [[Category: Swaminathan S]] | ||
Latest revision as of 09:21, 9 August 2023
STAPHYLOCOCCAL ENTEROTOXIN C2, MONOCLINIC FORM CRYSTALLIZED AT PH 8.0STAPHYLOCOCCAL ENTEROTOXIN C2, MONOCLINIC FORM CRYSTALLIZED AT PH 8.0
Structural highlights
FunctionENTC2_STAAU Staphylococcal enterotoxins cause the intoxication staphylococcal food poisoning syndrome. The illness characterized by high fever, hypotension, diarrhea, shock, and in some cases death. 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 three-dimensional structure of staphylococcal enterotoxin C2 (SEC2), a toxin as well as a superantigen, has been determined at various pH levels from two different crystal forms, tetragonal (pH 5.0, 5.5, 6.0 and 6.5) and monoclinic (pH 8.0) at 100 and 293 K, respectively, by the molecular-replacement method. Tetragonal crystals belong to space group P4(3)2(1)2, with unit-cell parameters a = b = 42.68, c = 289.15 A (at pH 5.0), and monoclinic crystals to space group P2(1), with unit-cell parameters a = 43.3, b = 70.6, c = 42.2 A, beta = 90.3 degrees. SEC2 contains a zinc-binding motif, D+HExxH, and accordingly a Zn atom has been identified. The coordination of the zinc ion suggests that it may be catalytic zinc rather than structural, but there is so far no biological evidence that it possesses catalytic activity. However, superantigen staphylococcal exfoliative toxins A and B have been shown to have enzymatic activity after their fold was identified to be similar to that of serine protease. The structure and its conformation are similar to the previously reported structures of SEC2. Though it was expected that the zinc ion may be leached out, as the histidines coordinating the zinc ion are expected to be protonated below pH 6.0, zinc is present at all pH values. The coordination distances to zinc increase with decreasing pH, with the distances being the least at pH 8.0. The results of automated model building using the ARP/wARP program for different data sets collected at various pH values are discussed. Structure of staphylococcal enterotoxin C2 at various pH levels.,Kumaran D, Eswaramoorthy S, Furey W, Sax M, Swaminathan S Acta Crystallogr D Biol Crystallogr. 2001 Sep;57(Pt 9):1270-5. Epub 2001, Aug 23. PMID:11526318[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References |
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