View source for 3tsj


==Crystal structure of Phl p 4, a grass pollen allergen with glucose dehydrogenase activity==
<StructureSection load='3tsj' size='340' side='right'caption='[[3tsj]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3tsj]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Phleum_pratense Phleum pratense]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3TSJ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3TSJ 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]] 2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FDA:DIHYDROFLAVINE-ADENINE+DINUCLEOTIDE'>FDA</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=3tsj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3tsj OCA], [https://pdbe.org/3tsj PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3tsj RCSB], [https://www.ebi.ac.uk/pdbsum/3tsj PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3tsj ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q2I6V7_PHLPR Q2I6V7_PHLPR] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
BACKGROUND: Phl p 4 is a major pollen allergen but exhibits lower allergenicity than other major allergens. The natural protein is glycosylated and shows cross-reactivity with related and structurally unrelated allergens. OBJECTIVE: We sought to determine the high-resolution crystal structure of Phl p 4 and to evaluate the immunologic properties of the recombinant allergen in comparison with natural Phl p 4. METHODS: Different isoallergens of Phl p 4 were expressed, and the nonglycosylated mutant was crystallized. The specific role of protein and carbohydrate epitopes for allergenicity was studied by using IgE inhibition and basophil release assays. RESULTS: The 3-dimensional structure was determined by using x-ray crystallography at a resolution of 1.9 A. The allergen is a glucose dehydrogenase with a bicovalently attached flavin adenine dinucleotide. Glycosylated and nonglycosylated recombinant Phl p 4 showed identical inhibition of IgE binding, but compared with natural Phl p 4, all recombinant isoforms displayed a reduced IgE-binding inhibition. However, the recombinant protein exhibited an approximately 10-fold higher potency in basophil release assays than the natural protein. CONCLUSION: The crystal structure reveals the compact globular nature of the protein, and the observed binding pocket implies the size of the natural substrate. Plant-derived cross-reactive carbohydrate determinants (CCDs) appear to reduce the allergenicity of the natural allergen, whereas the Pichia pastoris-derived glycosylation does not. Our results imply yet undescribed mechanism of how CCDs dampen the immune response, leading to a novel understanding of the role of CCDs.

Crystal structure and immunologic characterization of the major grass pollen allergen Phl p 4.,Zafred D, Nandy A, Pump L, Kahlert H, Keller W J Allergy Clin Immunol. 2013 Sep;132(3):696-703.e10. doi:, 10.1016/j.jaci.2013.03.021. Epub 2013 May 14. PMID:23683465<ref>PMID:23683465</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3tsj" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Phleum pratense]]
[[Category: Keller W]]
[[Category: Nandy A]]
[[Category: Zafred D]]