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1nsc

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Revision as of 10:04, 1 November 2017

INFLUENZA B VIRUS NEURAMINIDASE CAN SYNTHESIZE ITS OWN INHIBITOR

Structural highlights

1nsc is a 2 chain structure with sequence from Inbbe. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, ,
Activity:	Exo-alpha-sialidase, with EC number 3.2.1.18
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[NRAM_INBBE] 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 (By similarity).

Publication Abstract from PubMed

BACKGROUND: Neuraminidase, one of the two surface glycoproteins of influenza virus, cleaves terminal sialic acid residues from glycolipids or glycoproteins. Its crystal structure is known at high resolution, but the mechanism of glycosyl hydrolysis remains unclear. RESULTS: We have determined the crystal structure at 1.8 A resolution of two complexes of influenza B/Beijing neuraminidase containing either the reaction product, sialic acid, or the transition state analogue inhibitor, 2,3-dehydro-2-deoxy-N-acetylneuraminic acid (DANA). The sialic acid is bound in a distorted 'boat' conformation closely resembling that of bound DANA, stabilized by a conserved tyrosine residue (Tyr408). This distortion also gives rise to a suicidal side reaction that converts sialic acid to DANA at a low rate. CONCLUSIONS: The mechanism of neuraminidase action is distinct from that of other known glycosyl hydrolases. Substrate distortion appears to be the driving force in glycosyl bond hydrolysis and the proton required for catalysis can probably be donated by water, rather than by residues in the active site, thus allowing the enzyme to operate at high pH. The side reaction converting sialic acid to DANA appears reasonably favourable, and it is unclear how this is minimized by the enzyme.

Influenza B virus neuraminidase can synthesize its own inhibitor.,Burmeister WP, Henrissat B, Bosso C, Cusack S, Ruigrok RW Structure. 1993 Sep 15;1(1):19-26. PMID:8069621^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Burmeister WP, Henrissat B, Bosso C, Cusack S, Ruigrok RW. Influenza B virus neuraminidase can synthesize its own inhibitor. Structure. 1993 Sep 15;1(1):19-26. PMID:8069621

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1nsc"

Categories: Exo-alpha-sialidase | Inbbe | Burmeister, W P | Cusack, S | Ruigrok, R W.H

@@ Line 1: / Line 1: @@
 ==INFLUENZA B VIRUS NEURAMINIDASE CAN SYNTHESIZE ITS OWN INHIBITOR==
 <StructureSection load='1nsc' size='340' side='right' caption='[[1nsc]], [[Resolution|resolution]] 1.70&Aring;' scene=''>
@@ Line 5: / Line 6: @@
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=SIA:O-SIALIC+ACID'>SIA</scene></td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Exo-alpha-sialidase Exo-alpha-sialidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.18 3.2.1.18] </span></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1nsc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nsc OCA], [http://pdbe.org/1nsc PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1nsc RCSB], [http://www.ebi.ac.uk/pdbsum/1nsc PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1nsc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nsc OCA], [http://pdbe.org/1nsc PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1nsc RCSB], [http://www.ebi.ac.uk/pdbsum/1nsc PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1nsc ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 18: / Line 19: @@
 </div>
 <div class="pdbe-citations 1nsc" style="background-color:#fffaf0;"></div>
-==See Also==
-*[[Neuraminidase|Neuraminidase]]
 == References ==
 <references/>

1nsc

From Proteopedia

Revision as of 10:04, 1 November 2017

INFLUENZA B VIRUS NEURAMINIDASE CAN SYNTHESIZE ITS OWN INHIBITOR

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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