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3rpm
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| - | [[Image:3rpm.png|left|200px]] | ||
| - | < | + | ==Crystal structure of the first GH20 domain of a novel Beta-N-acetyl-hexosaminidase StrH from Streptococcus pneumoniae R6== |
| - | + | <StructureSection load='3rpm' size='340' side='right'caption='[[3rpm]], [[Resolution|resolution]] 2.10Å' scene=''> | |
| - | + | == Structural highlights == | |
| - | + | <table><tr><td colspan='2'>[[3rpm]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Strr6 Strr6]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3RPM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3RPM FirstGlance]. <br> | |
| - | + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1PE:PENTAETHYLENE+GLYCOL'>1PE</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene></td></tr> | |
| - | -- | + | <tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></td></tr> |
| - | + | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">strH ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=171101 STRR6])</td></tr> | |
| + | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Beta-N-acetylhexosaminidase Beta-N-acetylhexosaminidase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.52 3.2.1.52] </span></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=3rpm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3rpm OCA], [https://pdbe.org/3rpm PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3rpm RCSB], [https://www.ebi.ac.uk/pdbsum/3rpm PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3rpm ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | The beta-N-acetylhexosaminidase (EC 3.2.1.52) from glycoside hydrolase family 20 (GH20) catalyzes the hydrolysis of the beta-N-acetylglucosamine (NAG) group from the nonreducing end of various glycoconjugates. The putative surface-exposed N-acetylhexosaminidase StrH/Spr0057 from Streptococcus pneumoniae R6 was proved to contribute to the virulence by removal of beta(1,2)-linked NAG on host defense molecules following the cleavage of sialic acid and galactose by neuraminidase and beta-galactosidase, respectively. StrH is the only reported GH20 enzyme that contains a tandem repeat of two 53% sequence-identical catalytic domains (designated as GH20-1 and GH20-2, respectively). Here, we present the 2.1 A crystal structure of the N-terminal domain of StrH (residues Glu-175 to Lys-642) complexed with NAG. It adopts an overall structure similar to other GH20 enzymes: a (beta/alpha)(8) TIM barrel with the active site residing at the center of the beta-barrel convex side. The kinetic investigation using 4-nitrophenyl N-acetyl-beta-d-glucosaminide as the substrate demonstrated that GH20-1 had an enzymatic activity (k(cat)/K(m)) of one-fourth compared with GH20-2. The lower activity of GH20-1 could be attributed to the substitution of active site Cys-469 of GH20-1 to the counterpart Tyr-903 of GH20-2. A complex model of NAGbeta(1,2)Man at the active site of GH20-1 combined with activity assays of the corresponding site-directed mutants characterized two key residues Trp-443 and Tyr-482 at subsite +1 of GH20-1 (Trp-876 and Tyr-914 of GH20-2) that might determine the beta(1,2) substrate specificity. Taken together, these findings shed light on the mechanism of catalytic specificity toward the beta(1,2)-linked beta-N-acetylglucosides. | ||
| - | + | Structural basis for the substrate specificity of a novel beta-N-acetylhexosaminidase StrH protein from Streptococcus pneumoniae R6.,Jiang YL, Yu WL, Zhang JW, Frolet C, Di Guilmi AM, Zhou CZ, Vernet T, Chen Y J Biol Chem. 2011 Dec 16;286(50):43004-12. doi: 10.1074/jbc.M111.256578. Epub, 2011 Oct 19. PMID:22013074<ref>PMID:22013074</ref> | |
| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| + | </div> | ||
| + | <div class="pdbe-citations 3rpm" style="background-color:#fffaf0;"></div> | ||
| - | == | + | ==See Also== |
| - | [[ | + | *[[Beta-Hexosaminidase|Beta-Hexosaminidase]] |
| + | *[[Beta-Hexosaminidase 3D structures|Beta-Hexosaminidase 3D structures]] | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
[[Category: Beta-N-acetylhexosaminidase]] | [[Category: Beta-N-acetylhexosaminidase]] | ||
| - | [[Category: | + | [[Category: Large Structures]] |
| - | [[Category: Jiang, Y L | + | [[Category: Strr6]] |
| - | [[Category: Yu, W L | + | [[Category: Jiang, Y L]] |
| - | [[Category: Zhang, J W | + | [[Category: Yu, W L]] |
| + | [[Category: Zhang, J W]] | ||
[[Category: Beta-n-acetyl-hexosaminidase]] | [[Category: Beta-n-acetyl-hexosaminidase]] | ||
[[Category: Hydrolase]] | [[Category: Hydrolase]] | ||
[[Category: Tim barrel]] | [[Category: Tim barrel]] | ||
Current revision
Crystal structure of the first GH20 domain of a novel Beta-N-acetyl-hexosaminidase StrH from Streptococcus pneumoniae R6
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