View source for 9czb


==CryoEM structure of BoNT/E at pH5, class 1==
<StructureSection load='9czb' size='340' side='right'caption='[[9czb]], [[Resolution|resolution]] 3.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9czb]] is a 1 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=9CZB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9CZB FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.7&#8491;</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=9czb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9czb OCA], [https://pdbe.org/9czb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9czb RCSB], [https://www.ebi.ac.uk/pdbsum/9czb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9czb ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q54A79_CLOBO Q54A79_CLOBO] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Fast-acting botulinum neurotoxins (BoNTs) are highly desirable for both medical and aesthetic indications, but the underlying mechanism for the differing onset of BoNTs' action remains unknown. Here, we demonstrate that the "belt" of BoNTs, a largely unstructured loop wrapping around their catalytic light chain (LC), is key to onset of intoxication. The more flexible BoNT/E belt promotes quicker LC translocation into the neuronal cytosol, leading to faster onset of action compared to BoNT/A. Furthermore, we discover a "belt-buckle" checkpoint that regulates this process. By loosening the BoNT/A belt-buckle via protein engineering, we enhance its sensitivity to acidic pH, leading to an accelerated onset of action. Conversely, locking the belt-buckle with an antibody neutralizes BoNT/A. Our findings open avenues for developing fast-acting BoNTs and effective countermeasures.

A belt-buckle checkpoint regulates the onset of botulinum neurotoxin intoxication.,Chen B, Gao L, Bonninger M, Huang T, Krez N, Wen W, Bowen M, Lou J, Marks JD, Rummel A, Jin R Nat Commun. 2026 Jun 23;17(1):5562. doi: 10.1038/s41467-026-74499-7. PMID:42337249<ref>PMID:42337249</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9czb" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Clostridium botulinum]]
[[Category: Large Structures]]
[[Category: Gao L]]