View source for 2sim

==THE STRUCTURES OF SALMONELLA TYPHIMURIUM LT2 NEURAMINIDASE AND ITS COMPLEX WITH A TRANSITION STATE ANALOGUE AT 1.6 ANGSTROMS RESOLUTION==
<StructureSection load='2sim' size='340' side='right' caption='[[2sim]], [[Resolution|resolution]] 1.60&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2sim]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Salmonella_enterica_subsp._enterica_serovar_typhimurium Salmonella enterica subsp. enterica serovar typhimurium]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1sim 1sim]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2SIM OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2SIM FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=DAN:2-DEOXY-2,3-DEHYDRO-N-ACETYL-NEURAMINIC+ACID'>DAN</scene></td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">PSX62 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=90371 Salmonella enterica subsp. enterica serovar Typhimurium])</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=2sim FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2sim OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2sim RCSB], [http://www.ebi.ac.uk/pdbsum/2sim PDBsum]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/NANH_SALTY NANH_SALTY]] Cleaves the terminal sialic acid (N-acetyl neuraminic acid) from carbohydrate chains in glycoproteins providing free sialic acid which can be used as carbon and energy sources. Sialidases have been suggested to be pathogenic factors in microbial infections. 
== 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/si/2sim_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/chain_selection.php?pdb_ID=2ata ConSurf].
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== Publication Abstract from PubMed ==
The structure of Salmonella typhimurium LT2 neuraminidase (STNA) is reported here to a resolution of 1.6 angstroms together with the structures of three complexes of STNA with different inhibitors. The first is 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid (Neu5Ac2en or DANA), the second and third are phosphonate derivatives of N-acetyl-neuraminic acid (NANA) which have phosphonate groups at the C2 position equatorial (ePANA) and axial (aPANA) to the plane of the sugar ring. The complex structures are at resolutions of 1.6 angstroms, 1.6 angstroms and 1.9 angstroms, respectively. These analyses show the STNA active site to be topologically inflexible and the interactions to be dominated by the arginine triad, with the pyranose rings of the inhibitors undergoing distortion to occupy the space available. Solvent structure differs only around the third phosphonate oxygen, which attracts a potassium ion. The STNA structure is topologically identical to the previously reported influenza virus neuraminidase structures, although very different in detail; the root-mean-square (r.m.s) deviation for 210 C alpha positions considered equivalent is 2.28 angstroms (out of a total of 390 residues in influenza and 381 in STNA). The active site residues are more highly conserved, in that both the viral and bacterial structures contain an arginine triad, a hydrophobic pocket, a tyrosine and glutamic acid residue at the base of the site and a potential proton-donating aspartic acid. However, differences in binding to O4 and to the glycerol side-chain may reflect the different kinetics employed by the two enzymes.

The structures of Salmonella typhimurium LT2 neuraminidase and its complexes with three inhibitors at high resolution.,Crennell SJ, Garman EF, Philippon C, Vasella A, Laver WG, Vimr ER, Taylor GL J Mol Biol. 1996 Jun 7;259(2):264-80. PMID:8656428<ref>PMID:8656428</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Neuraminidase|Neuraminidase]]
== References ==
<references/>
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</StructureSection>
[[Category: Exo-alpha-sialidase]]
[[Category: Salmonella enterica subsp. enterica serovar typhimurium]]
[[Category: Crennell, S J]]
[[Category: Garman, E F]]
[[Category: Laver, W G]]
[[Category: Taylor, G L]]
[[Category: Vimr, E R]]
[[Category: Hydrolase]]