View source for 4zh7


==Structural basis of Lewisb antigen binding by the Helicobacter pylori adhesin BabA==
<StructureSection load='4zh7' size='340' side='right'caption='[[4zh7]], [[Resolution|resolution]] 2.12&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4zh7]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Helicobacter_pylori Helicobacter pylori]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4ZH7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4ZH7 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]] 2.12&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FUC:ALPHA-L-FUCOSE'>FUC</scene>, <scene name='pdbligand=GAL:BETA-D-GALACTOSE'>GAL</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=4zh7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4zh7 OCA], [https://pdbe.org/4zh7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4zh7 RCSB], [https://www.ebi.ac.uk/pdbsum/4zh7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4zh7 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q9ZKV2_HELPJ Q9ZKV2_HELPJ] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Helicobacter pylori is a leading cause of peptic ulceration and gastric cancer worldwide. To achieve colonization of the stomach, this Gram-negative bacterium adheres to Lewisb (Leb) antigens in the gastric mucosa using its outer membrane protein BabA. Structural information for BabA has been elusive, and thus, its molecular mechanism for recognizing Leb antigens remains unknown. We present the crystal structure of the extracellular domain of BabA, from H. pylori strain J99, in the absence and presence of Leb at 2.0- and 2.1-A resolutions, respectively. BabA is a predominantly alpha-helical molecule with a markedly kinked tertiary structure containing a single, shallow Leb binding site at its tip within a beta-strand motif. No conformational change occurs in BabA upon binding of Leb, which is characterized by low affinity under acidic [K D (dissociation constant) of ~227 muM] and neutral (K D of ~252 muM) conditions. Binding is mediated by a network of hydrogen bonds between Leb Fuc1, GlcNAc3, Fuc4, and Gal5 residues and a total of eight BabA amino acids (C189, G191, N194, N206, D233, S234, S244, and T246) through both carbonyl backbone and side-chain interactions. The structural model was validated through the generation of two BabA variants containing N206A and combined D233A/S244A substitutions, which result in a reduction and complete loss of binding affinity to Leb, respectively. Knowledge of the molecular basis of Leb recognition by BabA provides a platform for the development of therapeutics targeted at inhibiting H. pylori adherence to the gastric mucosa.

Structural basis of Lewis antigen binding by the adhesin BabA.,Hage N, Howard T, Phillips C, Brassington C, Overman R, Debreczeni J, Gellert P, Stolnik S, Winkler GS, Falcone FH Sci Adv. 2015 Aug 14;1(7):e1500315. eCollection 2015 Aug. PMID:26601230<ref>PMID:26601230</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4zh7" style="background-color:#fffaf0;"></div>

==See Also==
*[[Adhesin 3D structures|Adhesin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Helicobacter pylori]]
[[Category: Large Structures]]
[[Category: Brassington CA]]
[[Category: Debreczeni J]]
[[Category: Falcone FH]]
[[Category: Gellert P]]
[[Category: Hage N]]
[[Category: Howard T]]
[[Category: Overman R]]
[[Category: Phillips C]]
[[Category: Stolnik S]]
[[Category: Winkler GS]]