View source for 1nmc


==COMPLEX BETWEEN NC10 ANTI-INFLUENZA VIRUS NEURAMINIDASE SINGLE CHAIN ANTIBODY WITH A 15 RESIDUE LINKER AND INFLUENZA VIRUS NEURAMINIDASE==
<StructureSection load='1nmc' size='340' side='right'caption='[[1nmc]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1nmc]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Influenza_A_virus Influenza A virus] and [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NMC OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1NMC 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]] 2.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</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=1nmc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nmc OCA], [https://pdbe.org/1nmc PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1nmc RCSB], [https://www.ebi.ac.uk/pdbsum/1nmc PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1nmc ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/NRAM_I75A5 NRAM_I75A5] Catalyzes the removal of terminal sialic acid residues from viral and cellular glycoconjugates. Cleaves off the terminal sialic acids on the glycosylated HA during virus budding to facilitate virus release. Additionally helps virus spread through the circulation by further removing sialic acids from the cell surface. These cleavages prevent self-aggregation and ensure the efficient spread of the progeny virus from cell to cell. Otherwise, infection would be limited to one round of replication. Described as a receptor-destroying enzyme because it cleaves a terminal sialic acid from the cellular receptors. May facilitate viral invasion of the upper airways by cleaving the sialic acid moities on the mucin of the airway epithelial cells. Likely to plays a role in the budding process through its association with lipid rafts during intracellular transport. May additionally display a raft-association independent effect on budding. Plays a role in the determination of host range restriction on replication and virulence. Sialidase activity in late endosome/lysosome traffic seems to enhance virus replication.
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/nm/1nmc_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1nmc ConSurf].
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== Publication Abstract from PubMed ==
The structure of the complex between a recombinant single-chain Fv construct of antibody NC10 with a five-residue peptide linker between VH and VL (termed scFv(5)), and its antigen, tetrameric neuraminidase from influenza virus (NA), has been determined and refined at 2.5 A resolution. The antibody-antigen binding interface is very similar to that of a similar NC10 scFv-NA complex in which the scFv has a 15-residue peptide linker (scFv(15)), and the NC10 Fab-NA complex. However, scFv(5) and scFv(15) have different stoichiometries in solution. While scFv(15) is predominantly monomeric in solution, scFv(5) forms dimers exclusively, because the five-residue linker is not long enough to permit VH and VL domains from the same polypeptide associating and forming an antigen-binding site. Upon forming a complex with NA, scFv(15) forms a approximately 300 kDa complex corresponding to one NA tetramer binding four scFv(15) monomers, while scFv(5) forms a approximately 590 kDa complex, corresponding to two NA tetramers crosslinked by four bivalent scFv(5) dimers. However, the dimeric scFv(5) in the scFv(5)-NA crystals does not crosslink NA tetramers, and modelling studies indicate that it is not possible to pack four dimeric and simultaneously bivalent scFvs between the NA tetramers with only a five-residue linker between VH and VL. The inability arises from the exacting requirement to orient the two antigen-binding surfaces to bind the tetrameric NA antigen while avoiding steric clashes with NC10 scFv(5) dimers bound to other sites on the NA tetramer. The utility of bivalent or bifunctional scFvs with short linkers may therefore be restricted by the steric constraints imposed by binding multivalent antigens.

Three-dimensional structures of single-chain Fv-neuraminidase complexes.,Malby RL, McCoy AJ, Kortt AA, Hudson PJ, Colman PM J Mol Biol. 1998 Jun 19;279(4):901-10. PMID:9642070<ref>PMID:9642070</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]]
*[[Monoclonal Antibodies 3D structures|Monoclonal Antibodies 3D structures]]
*[[Neuraminidase 3D structures|Neuraminidase 3D structures]]
*[[3D structures of non-human antibody|3D structures of non-human antibody]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Influenza A virus]]
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Colman PM]]
[[Category: Hudson PJ]]
[[Category: Kortt AA]]
[[Category: Malby RL]]
[[Category: Mccoy AJ]]