View source for 3gvk


==Crystal structure of endo-neuraminidase NF mutant==
<StructureSection load='3gvk' size='340' side='right'caption='[[3gvk]], [[Resolution|resolution]] 1.84&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3gvk]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_phage_K1F Escherichia phage K1F]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3GVK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3GVK 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]] 1.84&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=SIA:O-SIALIC+ACID'>SIA</scene>, <scene name='pdbligand=SLB:5-N-ACETYL-BETA-D-NEURAMINIC+ACID'>SLB</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=3gvk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3gvk OCA], [https://pdbe.org/3gvk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3gvk RCSB], [https://www.ebi.ac.uk/pdbsum/3gvk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3gvk ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/FIBER_BPK1F FIBER_BPK1F] Receptor binding protein, which mediates the attachment to the host capsule (PubMed:20096705, PubMed:3546309). Degrades the alpha-2,8-linked polysialic acid of E.coli K1 capsule by cleaving within the polymer chain of polysialic acid (PubMed:3546309).<ref>PMID:20096705</ref> <ref>PMID:3546309</ref>   The C-terminal chaperone protein mediates homotrimerization and proper folding of the catalytic endo-N trimer.<ref>PMID:12556457</ref> 
== 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/gv/3gvk_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=3gvk ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
An alpha-2,8-linked polysialic acid (polySia) capsule confers immune tolerance to neuroinvasive, pathogenic prokaryotes such as Escherichia coli K1 and Neisseria meningitidis and supports host infection by means of molecular mimicry. Bacteriophages of the K1 family, infecting E. coli K1, specifically recognize and degrade this polySia capsule utilizing tailspike endosialidases. While the crystal structure for the catalytic domain of the endosialidase of bacteriophage K1F (endoNF) has been solved, there is yet no structural information on the mode of polySia binding and cleavage available. The crystal structure of activity deficient active-site mutants of the homotrimeric endoNF cocrystallized with oligomeric sialic acid identified three independent polySia binding sites in each endoNF monomer. The bound oligomeric sialic acid displays distinct conformations at each site. In the active site, a Sia(3) molecule is bound in an extended conformation representing the enzyme-product complex. Structural and biochemical data supported by molecular modeling enable to propose a reaction mechanism for polySia cleavage by endoNF.

Structural basis for the recognition and cleavage of polysialic acid by the bacteriophage K1F tailspike protein EndoNF.,Schulz EC, Schwarzer D, Frank M, Stummeyer K, Muhlenhoff M, Dickmanns A, Gerardy-Schahn R, Ficner R J Mol Biol. 2010 Mar 19;397(1):341-51. Epub 2010 Jan 22. PMID:20096705<ref>PMID:20096705</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3gvk" style="background-color:#fffaf0;"></div>

==See Also==
*[[Neuraminidase 3D structures|Neuraminidase 3D structures]]
*[[Tailspike protein 3D structures|Tailspike protein 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia phage K1F]]
[[Category: Large Structures]]
[[Category: Dickmanns A]]
[[Category: Ficner R]]
[[Category: Schulz EC]]