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2ctx
From Proteopedia
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| - | [[Image:2ctx.jpg|left|200px]]<br /><applet load="2ctx" size="350" color="white" frame="true" align="right" spinBox="true" | ||
| - | caption="2ctx, resolution 2.4Å" /> | ||
| - | '''THE REFINED CRYSTAL STRUCTURE OF ALPHA-COBRATOXIN FROM NAJA NAJA SIAMENSIS AT 2.4-ANGSTROMS RESOLUTION'''<br /> | ||
| - | == | + | ==THE REFINED CRYSTAL STRUCTURE OF ALPHA-COBRATOXIN FROM NAJA NAJA SIAMENSIS AT 2.4-ANGSTROMS RESOLUTION== |
| + | <StructureSection load='2ctx' size='340' side='right'caption='[[2ctx]], [[Resolution|resolution]] 2.40Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[2ctx]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Naja_naja Naja naja]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2CTX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2CTX 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='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2ctx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ctx OCA], [https://pdbe.org/2ctx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ctx RCSB], [https://www.ebi.ac.uk/pdbsum/2ctx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ctx ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/3L23_NAJNA 3L23_NAJNA] Binds with high affinity to muscular (alpha-1/CHRNA1) and neuronal (alpha-7/CHRNA7) nicotinic acetylcholine receptor (nAChR) and inhibits acetylcholine from binding to the receptor, thereby impairing neuromuscular and neuronal transmission.[UniProtKB:P60615] | ||
| + | == 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/ct/2ctx_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=2ctx ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
The crystal structure of the "long" alpha-neurotoxin alpha-cobratoxin was refined to an R-factor of 19.5% using 3271 x-ray data to 2.4-A resolution. The polypeptide chain forms three loops, I, II, III, knotted together by four disulfide bridges, with the most prominent, loop II, containing another disulfide close to its lower tip. Loop I is stabilized by one beta-turn and two beta-sheet hydrogen bonds; loop II by eight beta-sheet hydrogen bonds, with the tip folded into two distorted right-handed helical turns stabilized by two alpha-helical and two beta-turn hydrogen bonds; and loop III by hydrophobic interactions and one beta-turn. Loop II and one strand of loop III form an antiparallel triple-pleated beta-sheet, and tight anchoring of the Asn63 side chain fixes the tail segment. In the crystal lattice, the alpha-cobratoxin molecules dimerize by beta-sheet formation between strands 53 and 57 of symmetry-related molecules. Because such interactions are found also in a cardiotoxin and alpha-bungarotoxin, this could be of importance for interaction with acetylcholine receptor. | The crystal structure of the "long" alpha-neurotoxin alpha-cobratoxin was refined to an R-factor of 19.5% using 3271 x-ray data to 2.4-A resolution. The polypeptide chain forms three loops, I, II, III, knotted together by four disulfide bridges, with the most prominent, loop II, containing another disulfide close to its lower tip. Loop I is stabilized by one beta-turn and two beta-sheet hydrogen bonds; loop II by eight beta-sheet hydrogen bonds, with the tip folded into two distorted right-handed helical turns stabilized by two alpha-helical and two beta-turn hydrogen bonds; and loop III by hydrophobic interactions and one beta-turn. Loop II and one strand of loop III form an antiparallel triple-pleated beta-sheet, and tight anchoring of the Asn63 side chain fixes the tail segment. In the crystal lattice, the alpha-cobratoxin molecules dimerize by beta-sheet formation between strands 53 and 57 of symmetry-related molecules. Because such interactions are found also in a cardiotoxin and alpha-bungarotoxin, this could be of importance for interaction with acetylcholine receptor. | ||
| - | + | The refined crystal structure of alpha-cobratoxin from Naja naja siamensis at 2.4-A resolution.,Betzel C, Lange G, Pal GP, Wilson KS, Maelicke A, Saenger W J Biol Chem. 1991 Nov 15;266(32):21530-6. PMID:1939183<ref>PMID:1939183</ref> | |
| - | + | ||
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| + | <div class="pdbe-citations 2ctx" style="background-color:#fffaf0;"></div> | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Large Structures]] | ||
[[Category: Naja naja]] | [[Category: Naja naja]] | ||
| - | + | [[Category: Betzel C]] | |
| - | [[Category: Betzel | + | [[Category: Lange G]] |
| - | [[Category: Lange | + | [[Category: Maelicke A]] |
| - | [[Category: Maelicke | + | [[Category: Pal GP]] |
| - | [[Category: Pal | + | [[Category: Saenger W]] |
| - | [[Category: Saenger | + | [[Category: Wilson KS]] |
| - | [[Category: Wilson | + | |
| - | + | ||
| - | + | ||
| - | + | ||
Current revision
THE REFINED CRYSTAL STRUCTURE OF ALPHA-COBRATOXIN FROM NAJA NAJA SIAMENSIS AT 2.4-ANGSTROMS RESOLUTION
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Categories: Large Structures | Naja naja | Betzel C | Lange G | Maelicke A | Pal GP | Saenger W | Wilson KS
