View source for 5swa


==Crystal structure of N-glycan transport solute binding protein (NgtS) from Streptococcus pneumoniae in complex with Man1GlcNAc==
<StructureSection load='5swa' size='340' side='right'caption='[[5swa]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5swa]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptococcus_pneumoniae Streptococcus pneumoniae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5SWA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5SWA 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]] 3&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=BR:BROMIDE+ION'>BR</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=5swa FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5swa OCA], [https://pdbe.org/5swa PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5swa RCSB], [https://www.ebi.ac.uk/pdbsum/5swa PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5swa ProSAT]</span></td></tr>
</table>
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== Publication Abstract from PubMed ==
The carbohydrate-rich coating of human tissues and cells provide a first point of contact for colonizing and invading bacteria. Commensurate with N-glycosylation being an abundant form of protein glycosylation that has critical functional roles in the host, some host-adapted bacteria possess the machinery to process N-linked glycans. The human pathogen Streptococcus pneumoniae depolymerizes complex N-glycans with enzymes that sequentially trim a complex N-glycan down to the Man3GlcNAc2 core prior to the release of the glycan from the protein by endo-beta-N-acetylglucosaminidase (EndoD), which cleaves between the two GlcNAc residues. Here we examine the capacity of S. pneumoniae to process high-mannose N-glycans and transport the products. Through biochemical and structural analyses we demonstrate that S. pneumoniae also possesses an alpha-(1,2)-mannosidase (SpGH92). This enzyme has the ability to trim the terminal alpha-(1,2)-linked mannose residues of high-mannose N-glycans to generate Man5GlcNAc2. Through this activity SpGH92 is able to produce a substrate for EndoD, which is not active on high-mannose glycans with alpha-(1,2)-linked mannose residues. Binding studies and X-ray crystallography show that NgtS, the solute binding protein of an ABC transporter (ABCNG), is able to bind Man5GlcNAc, a product of EndoD activity, with high affinity. Finally, we evaluated the contribution of EndoD and ABCNG to growth of S. pneumoniae on a model N-glycosylated glycoprotein, and the contribution of these enzymes and SpGH92 to virulence in a mouse model. We found that both EndoD and ABCNG contribute to growth of S. pneumoniae, but that only SpGH92 and EndoD contribute to virulence. Therefore, N-glycan processing, but not transport of the released glycan, is required for full virulence in S. pneumoniae. To conclude, we synthesize our findings into a model of N-glycan processing by S. pneumoniae in which both complex and high-mannose N-glycans are targeted, and in which the two arms of this degradation pathway converge at ABCNG.

Molecular Characterization of N-glycan Degradation and Transport in Streptococcus pneumoniae and Its Contribution to Virulence.,Robb M, Hobbs JK, Woodiga SA, Shapiro-Ward S, Suits MD, McGregor N, Brumer H, Yesilkaya H, King SJ, Boraston AB PLoS Pathog. 2017 Jan 5;13(1):e1006090. doi: 10.1371/journal.ppat.1006090., eCollection 2017 Jan. PMID:28056108<ref>PMID:28056108</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Streptococcus pneumoniae]]
[[Category: Boraston AB]]
[[Category: Robb M]]