View source for 1w21


==Structure of Neuraminidase from English duck subtype N6 complexed with 30 mM sialic acid (NANA, Neu5Ac), crystal soaked for 43 hours at 291 K.==
<StructureSection load='1w21' size='340' side='right'caption='[[1w21]], [[Resolution|resolution]] 2.08&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1w21]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Influenza_A_virus Influenza A virus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1W21 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1W21 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]] 2.08&#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=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=SIA:O-SIALIC+ACID'>SIA</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=1w21 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1w21 OCA], [https://pdbe.org/1w21 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1w21 RCSB], [https://www.ebi.ac.uk/pdbsum/1w21 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1w21 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/NRAM_I56A2 NRAM_I56A2] 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/w2/1w21_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.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=1w21 ConSurf].
<div style="clear:both"></div>

==See Also==
*[[Neuraminidase 3D structures|Neuraminidase 3D structures]]
__TOC__
</StructureSection>
[[Category: Influenza A virus]]
[[Category: Large Structures]]
[[Category: Crennell SJ]]
[[Category: Garman EF]]
[[Category: Laver WG]]
[[Category: Rudino-Pinera E]]
[[Category: Tunnah P]]
[[Category: Webster RG]]