7n18

<StructureSection load='7n18' size='340' side='right'caption='[[7n18]], [[Resolution|resolution]] 2.03&Aring;' scene=''>

<table><tr><td colspan='2'>[[7n18]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Clostridium_botulinum Clostridium botulinum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7N18 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7N18 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=C7I:(3R)-3-(4-chlorophenyl)-N,5-dihydroxypentanamide'>C7I</scene>, <scene name='pdbligand=C8I:(3S)-3-(4-chlorophenyl)-N,5-dihydroxypentanamide'>C8I</scene>, <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=7n18 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7n18 OCA], [https://pdbe.org/7n18 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7n18 RCSB], [https://www.ebi.ac.uk/pdbsum/7n18 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7n18 ProSAT]</span></td></tr>

== Function ==

[[https://www.uniprot.org/uniprot/BXA1_CLOBH BXA1_CLOBH]] Inhibits acetylcholine release. The botulinum toxin binds with high affinity to peripheral neuronal presynaptic membrane to the secretory vesicle protein SV2. It binds directly to the largest luminal loop of SV2A, SV2B and SV2C. It is then internalized by receptor-mediated endocytosis. The C-terminus of the heavy chain (H) is responsible for the adherence of the toxin to the cell surface while the N-terminus mediates transport of the light chain from the endocytic vesicle to the cytosol. After translocation, the light chain (L) hydrolyzes the 197-Gln-|-Arg-198 bond in SNAP-25, thereby blocking neurotransmitter release. Inhibition of acetylcholine release results in flaccid paralysis, with frequent heart or respiratory failure.

[[Category: Clostridium botulinum]]