View source for 8fax


==Fab 1249A8-MERS Stem Helix Complex==
<StructureSection load='8fax' size='340' side='right'caption='[[8fax]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8fax]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Middle_East_respiratory_syndrome-related_coronavirus Middle East respiratory syndrome-related coronavirus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8FAX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8FAX 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]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=8fax FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8fax OCA], [https://pdbe.org/8fax PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8fax RCSB], [https://www.ebi.ac.uk/pdbsum/8fax PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8fax ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SPIKE_MERS1 SPIKE_MERS1] Attaches the virion to the cell membrane by interacting with host receptor, initiating the infection (By similarity). Interacts with host DPP4 to mediate virla entry.[HAMAP-Rule:MF_04099]<ref>PMID:23486063</ref>   Mediates fusion of the virion and cellular membranes by acting as a class I viral fusion protein. Under the current model, the protein has at least three conformational states: pre-fusion native state, pre-hairpin intermediate state, and post-fusion hairpin state. During viral and target cell membrane fusion, the coiled coil regions (heptad repeats) assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain. The formation of this structure appears to drive apposition and subsequent fusion of viral and target cell membranes.[HAMAP-Rule:MF_04099]  Acts as a viral fusion peptide which is unmasked following S2 cleavage occurring upon virus endocytosis.[HAMAP-Rule:MF_04099]
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== Publication Abstract from PubMed ==
Monoclonal antibodies that retain neutralizing activity against multiple coronavirus (CoV) lineages and variants of concern (VoC) must be developed to protect against future pandemics. These broadly neutralizing MAbs (BNMAbs) may be used as therapeutics and/or to assist in the rational design of vaccines that induce BNMAbs. 1249A8 is a BNMAb that targets the stem helix (SH) region of CoV spike (S) protein and neutralizes Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) original strain, delta, and omicron VoC, Severe Acute Respiratory Syndrome CoV (SARS-CoV), and Middle East Respiratory Syndrome CoV (MERS-CoV). To understand its mechanism of action, the crystal structure of 1249A8 bound to a MERS-CoV SH peptide was determined at 2.1 A resolution. BNMAb 1249A8 mimics the SARS-CoV-2 S loop residues 743-749, which interacts with the N-terminal end of the SH helix in the S post-fusion conformation. The conformation of 1249A8-bound SH is distinct from the SH conformation observed in the post-fusion SARS-CoV-2 S structure, suggesting 1249A8 disrupts the secondary structure and refolding events required for CoV post-fusion S to initiate membrane fusion and ultimately infection. This study provides novel insights into the neutralization mechanisms of SH-targeting CoV BNMAbs that may inform vaccine development and the design of optimal BNMAb therapeutics.

Structure and epitope of a neutralizing monoclonal antibody that targets the stem helix of beta coronaviruses.,Deshpande A, Schormann N, Piepenbrink MS, Martinez Sobrido L, Kobie JJ, Walter MR FEBS J. 2023 Jul;290(13):3422-3435. doi: 10.1111/febs.16777. Epub 2023 Apr 4. PMID:37014961<ref>PMID:37014961</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8fax" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Middle East respiratory syndrome-related coronavirus]]
[[Category: Deshpande A]]
[[Category: Kobie JJ]]
[[Category: Martinez-Sobrido L]]
[[Category: Piepenbrink MS]]
[[Category: Schormann N]]
[[Category: Walter MR]]