View source for 1fss


==ACETYLCHOLINESTERASE (E.C. 3.1.1.7) COMPLEXED WITH FASCICULIN-II==
<StructureSection load='1fss' size='340' side='right' caption='[[1fss]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1fss]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Dendroaspis_angusticeps Dendroaspis angusticeps] and [http://en.wikipedia.org/wiki/Torpedo_californica Torpedo californica]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1FSS OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1FSS FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Acetylcholinesterase Acetylcholinesterase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.7 3.1.1.7] </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=1fss FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1fss OCA], [http://pdbe.org/1fss PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1fss RCSB], [http://www.ebi.ac.uk/pdbsum/1fss PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1fss ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/ACES_TORCA ACES_TORCA]] Terminates signal transduction at the neuromuscular junction by rapid hydrolysis of the acetylcholine released into the synaptic cleft. May be involved in cell-cell interactions. 
== 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/fs/1fss_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=1fss ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
BACKGROUND: Fasciculin (FAS), a 61-residue polypeptide purified from mamba venom, is a three-fingered toxin which is a powerful reversible inhibitor of acetylcholinesterase (AChE). Solution of the three-dimensional structure of the AChE/FAS complex would provide the first structure of a three-fingered toxin complexed with its target. RESULTS: The structure of a complex between Torpedo californica AChE and fasciculin-II (FAS-II), from the venom of the green mamba (Dendroaspis angusticeps) was solved by molecular replacement techniques, and refined at 3.0 A resolution to an R-factor of 0.231. The structure reveals a stoichiometric complex with one FAS molecule bound to each AChE subunit. The AChE and FAS conformations in the complex are very similar to those in their isolated structures. FAS is bound at the 'peripheral' anionic site of AChE, sealing the narrow gorge leading to the active site, with the dipole moments of the two molecules roughly aligned. The high affinity of FAS for AChE is due to a remarkable surface complementarity, involving a large contact area (approximately 2000 A2) and many residues either unique to FAS or rare in other three-fingered toxins. The first loop, or finger, of FAS reaches down the outer surface of the thin aspect of the gorge. The second loop inserts into the gorge, with an unusual stacking interaction between Met33 in FAS and Trp279 in AChE. The third loop points away from the gorge, but the C-terminal residue makes contact with the enzyme. CONCLUSIONS: Two conserved aromatic residues in the AChE peripheral anionic site make important contacts with FAS. The absence of these residues from chicken and insect AChEs and from butyrylcholinesterase explains the very large reduction in the affinity of these enzymes for FAS. Several basic residues in FAS make important contacts with AChE. The complementarity between FAS and AChE is unusual, inasmuch as it involves a number of charged residues, but lacks any intermolecular salt linkages.

Crystal structure of an acetylcholinesterase-fasciculin complex: interaction of a three-fingered toxin from snake venom with its target.,Harel M, Kleywegt GJ, Ravelli RB, Silman I, Sussman JL Structure. 1995 Dec 15;3(12):1355-66. PMID:8747462<ref>PMID:8747462</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1fss" style="background-color:#fffaf0;"></div>

==See Also==
*[[Acetylcholinesterase 3D structures|Acetylcholinesterase 3D structures]]
*[[Acetylcholinesterase: Substrate Traffic and Inhibition|Acetylcholinesterase: Substrate Traffic and Inhibition]]
*[[3D structures of acetylcholinesterase|3D structures of acetylcholinesterase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Acetylcholinesterase]]
[[Category: Dendroaspis angusticeps]]
[[Category: Torpedo californica]]
[[Category: Harel, M]]
[[Category: Kleywegt, G J]]
[[Category: Silman, I]]
[[Category: Sussman, J L]]