View source for 6ksn


==Structure of a Zn-bound camelid single domain antibody==
<StructureSection load='6ksn' size='340' side='right'caption='[[6ksn]], [[Resolution|resolution]] 2.15&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6ksn]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Camelus_dromedarius Camelus dromedarius]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6KSN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6KSN 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]] 2.15&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=6ksn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ksn OCA], [https://pdbe.org/6ksn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6ksn RCSB], [https://www.ebi.ac.uk/pdbsum/6ksn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6ksn ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Single chain antibodies from camelids have served as powerful tools ranging from diagnostics and therapeutics to crystallization chaperones meant to study protein structure and function. In this study, we isolated a single chain antibody from an Indian dromedary camel (ICab) immunized against a bacterial 14TM helix transporter, NorC, from Staphylococcus aureus We identified this antibody in a yeast display screen built from mononuclear cells isolated from the immunized camel and purified the antibody from E.coli after refolding it from inclusion bodies. The X-ray structure of the antibody at 2.15 A resolution revealed a unique feature within its CDR3 loop, which harbors a Zn(2+)-binding site that substitutes for a loop-stabilizing disulfide bond. We performed mutagenesis to compromise the Zn(2+)-binding site and observed that this change severely hampered antibody stability and its ability to interact with the antigen. The lack of bound Zn(2+)also made the CDR3 loop highly flexible as observed in all-atom simulations. Using confocal imaging of NorC-expressing E.coli spheroplasts, we found that the ICab interacts with the extracellular surface of NorC. This suggests that the ICab could be a valuable tool for detecting methicillin-resistant S.aureus (MRSA) strains that express efflux transporters such as NorC in hospital and community settings.

Isolation and structural characterization of a Zn(2+)-bound single-domain antibody against NorC, a putative multi-drug efflux transporter in bacteria.,Kumar S, Ithayaraja M, Athreya A, Ranjan R, Penmatsa A J Biol Chem. 2019 Nov 7. pii: RA119.010902. doi: 10.1074/jbc.RA119.010902. PMID:31699895<ref>PMID:31699895</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6ksn" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Camelus dromedarius]]
[[Category: Large Structures]]
[[Category: Athreya A]]
[[Category: Kumar S]]
[[Category: Penmatsa A]]