1nsd: Difference between revisions
No edit summary |
No edit summary |
||
| Line 3: | Line 3: | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[1nsd]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Influenza_b_virus_(strain_b/beijing/1/87) Influenza b virus (strain b/beijing/1/87)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NSD OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1NSD FirstGlance]. <br> | <table><tr><td colspan='2'>[[1nsd]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Influenza_b_virus_(strain_b/beijing/1/87) Influenza b virus (strain b/beijing/1/87)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NSD OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1NSD FirstGlance]. <br> | ||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=DAN:2-DEOXY-2,3-DEHYDRO-N-ACETYL-NEURAMINIC+ACID'>DAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>< | </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=DAN:2-DEOXY-2,3-DEHYDRO-N-ACETYL-NEURAMINIC+ACID'>DAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene></td></tr> | ||
<tr><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='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><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1nsd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nsd OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1nsd RCSB], [http://www.ebi.ac.uk/pdbsum/1nsd 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=1nsd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nsd OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1nsd RCSB], [http://www.ebi.ac.uk/pdbsum/1nsd PDBsum]</span></td></tr> | ||
<table> | </table> | ||
== Function == | |||
[[http://www.uniprot.org/uniprot/NRAM_INBBE 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). | |||
<div style="background-color:#fffaf0;"> | <div style="background-color:#fffaf0;"> | ||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
| Line 23: | Line 25: | ||
</StructureSection> | </StructureSection> | ||
[[Category: Exo-alpha-sialidase]] | [[Category: Exo-alpha-sialidase]] | ||
[[Category: Burmeister, W P | [[Category: Burmeister, W P]] | ||
[[Category: Cusack, S | [[Category: Cusack, S]] | ||
[[Category: Ruigrok, R W.H | [[Category: Ruigrok, R W.H]] | ||
[[Category: Hydrolase-hydrolase inhibitor complex]] | [[Category: Hydrolase-hydrolase inhibitor complex]] | ||
[[Category: O-glycosyl]] | [[Category: O-glycosyl]] | ||
Revision as of 23:27, 25 December 2014
INFLUENZA B VIRUS NEURAMINIDASE CAN SYNTHESIZE ITS OWN INHIBITORINFLUENZA B VIRUS NEURAMINIDASE CAN SYNTHESIZE ITS OWN INHIBITOR
Structural highlights
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 PubMedBACKGROUND: 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. See AlsoReferences |
| ||||||||||||||||||