View source for 4nbx


==Crystal Structure of Clostridium difficile Toxin A fragment TcdA-A1 Bound to A20.1 VHH==
<StructureSection load='4nbx' size='340' side='right'caption='[[4nbx]], [[Resolution|resolution]] 1.75&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4nbx]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Clostridioides_difficile Clostridioides difficile] and [https://en.wikipedia.org/wiki/Lama_glama Lama glama]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4NBX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4NBX 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]] 1.75&#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=4nbx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4nbx OCA], [https://pdbe.org/4nbx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4nbx RCSB], [https://www.ebi.ac.uk/pdbsum/4nbx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4nbx ProSAT]</span></td></tr>
</table>
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== Publication Abstract from PubMed ==
Clostridium difficile infection (CDI) is a serious and highly prevalent nosocomial disease in which the two large, Rho-glucosylating toxins TcdA and TcdB are the main virulence factors. We report for the first time crystal structures revealing how neutralizing and non-neutralizing single-domain antibodies (sdAbs) recognize the receptor-binding domains (RBDs) of TcdA and TcdB. Surprisingly, the complexes formed by two neutralizing antibodies recognizing TcdA do not show direct interference with the previously identified carbohydrate-binding sites, suggesting that neutralization of toxin activity may be mediated by mechanisms distinct from steric blockage of receptor binding. A camelid sdAb complex also reveals the molecular structure of the TcdB RBD for the first time, facilitating the crystallization of a strongly negatively charged protein fragment that has resisted previous attempts at crystallization and structure determination. Electrospray ionization mass spectrometry measurements confirm the stoichiometries of sdAbs observed in the crystal structures. These studies indicate how key epitopes in the RBDs from TcdA and TcdB are recognized by sdAbs, providing molecular insights into toxin structure and function, and providing for the first time a basis for the design of highly specific toxin-specific therapeutic and diagnostic agents.

Structural Basis for Antibody Recognition in the Receptor-Binding Domains of Toxins A and B from Clostridium difficile.,Murase T, Eugenio L, Schorr M, Hussack G, Tanha J, Kitova EN, Klassen JS, Ng KK J Biol Chem. 2013 Dec 5. PMID:24311789<ref>PMID:24311789</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Antibody 3D structures|Antibody 3D structures]]
*[[3D structures of non-human antibody|3D structures of non-human antibody]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Clostridioides difficile]]
[[Category: Lama glama]]
[[Category: Large Structures]]
[[Category: Eugenio L]]
[[Category: Hussack G]]
[[Category: Kitova EN]]
[[Category: Klassen JS]]
[[Category: Murase T]]
[[Category: Ng KKS]]
[[Category: Schorr M]]
[[Category: Tanha J]]