View source for 6jqf


==Crystallization analysis of a beta-N-acetylhexosaminidase (Am2136) from Akkermansia muciniphila==
<StructureSection load='6jqf' size='340' side='right'caption='[[6jqf]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6jqf]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Akkermansia_muciniphila_ATCC_BAA-835 Akkermansia muciniphila ATCC BAA-835]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6JQF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6JQF 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]] 1.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</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=6jqf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6jqf OCA], [https://pdbe.org/6jqf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6jqf RCSB], [https://www.ebi.ac.uk/pdbsum/6jqf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6jqf ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/H2136_AKKM8 H2136_AKKM8] Potentially capable of cleaving the specific glycoside linkages in the process of mucin degradation in human intestinal tract (Probable). Hydrolyzes synthetic substrate pNP-beta-GlcNAc with high activity and pNP-beta-GalNAc to a lot lesser extent. Does not hydrolyze pNP-alpha-GalNAc.<ref>PMID:31345574</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
In this paper, we characterized Am2136 as a beta-N-acetylhexosaminidase from Akkermansia muciniphila to perform the biochemical characteristics and the crystal structure of selenomethionine-labeled Am2136 with GlcNAc complex. Crystallographic evidence suggests that an oxazolinium ion was formed intermediately by the 2-acetamido group during the substrate-assisted catalytic procedure. Structural and kinetic analysis of native Am2136 and D412A, E413A mutants were investigated and the results revealed substantial difference. The Kcat/Km value of D412A was decreased 4297-fold compared to native Am2136 revealed that mutation of Asp-412 results in preventing the 2-acetamido substituent from providing anchimeric assistance and thus reducing the catalytic efficiency. Moreover, Am2136 has a wide dependence on pH and temperature, while sensitive to divalent metal ions such as Ca(2+) and Mn(2+). These biochemical and crystallographic results provide evidences that Asp-412 residue assists to orient the 2-acetamido group for catalysis. Based on crystallographic evidence and sequence alignment with other GH family 20 enzymes, Asp-412 residue is possibly fundamental for Am2136 during substrate-assisted catalysis.

Biochemical characteristics and crystallographic evidence for substrate-assisted catalysis of a beta-N-acetylhexosaminidase in Akkermansia muciniphila.,Chen X, Li M, Wang Y, Tang R, Zhang M Biochem Biophys Res Commun. 2019 Sep 10;517(1):29-35. doi:, 10.1016/j.bbrc.2019.06.150. Epub 2019 Jul 23. PMID:31345574<ref>PMID:31345574</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6jqf" style="background-color:#fffaf0;"></div>

==See Also==
*[[Beta-N-acetylhexosaminidase 3D structures|Beta-N-acetylhexosaminidase 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Akkermansia muciniphila ATCC BAA-835]]
[[Category: Large Structures]]
[[Category: Chen X]]
[[Category: Zhang M]]