View source for 1ibg


==STRUCTURE AND SPECIFICITY OF THE ANTI-DIGOXIN ANTIBODY 40-50==
<StructureSection load='1ibg' size='340' side='right'caption='[[1ibg]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1ibg]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1IBG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1IBG 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]] 2.7&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CU:COPPER+(II)+ION'>CU</scene>, <scene name='pdbligand=OBN:OUABAIN'>OBN</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=1ibg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ibg OCA], [https://pdbe.org/1ibg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1ibg RCSB], [https://www.ebi.ac.uk/pdbsum/1ibg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1ibg ProSAT]</span></td></tr>
</table>
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ib/1ibg_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1ibg ConSurf].
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== Publication Abstract from PubMed ==
We determined the sequence, specificity for structurally related cardenolides, and three-dimensional structure of the anti-digoxin antibody 40-50 Fab in complex with ouabain. The 40-50 antibody does not share close sequence homology with other high-affinity anti-digoxin antibodies. Measurement of the binding constants of structurally distinct digoxin analogs indicated a well-defined specificity pattern also distinct from other anti-digoxin antibodies. The 40-50-ouabain Fab complex crystallizes in space group C2 with cell dimensions of a = 93.7 A, b = 84.8 A, c = 70.1 A, beta = 128.0 degrees. The structure of the complex was determined by X-ray crystallography and refined at a resolution of 2.7 A. The hapten is bound in a pocket extending as a groove from the center of the combining site across the light chain variable domain, with five of the six complementarity-determining regions involved in interactions with the hapten. Approximately three-quarters of the hapten surface area is buried in the complex; two hydrogen bonds are formed between the antibody and hapten. The surface area of the antibody combining site buried by ouabain is contributed equally by the light and heavy chain variable domains. Over half of the surface area buried on the Fab consists of the aromatic side-chains. The surface complementarity between hapten and antibody is sufficient to make the complex specific for only one lactone ring conformation in the hapten. The crystal structure of the 40-50-ouabain complex allows qualitative explanation of the observed fine specificities of 40-50, including that for the binding of haptens substituted at the 16 and 12 positions. Comparison of the crystal structures of 40-50 complexed with ouabain and the previously determined 26-10 anti-digoxin Fab complexed with digoxin, demonstrates that the antibodies bind these structurally related haptens in different orientations, consistent with their different fine specificities. These results demonstrate that the immune system can generate antibodies that provide diverse structural solutions to the binding of even small molecules.

Structure and specificity of the anti-digoxin antibody 40-50.,Jeffrey PD, Schildbach JF, Chang CY, Kussie PH, Margolies MN, Sheriff S J Mol Biol. 1995 Apr 28;248(2):344-60. PMID:7739045<ref>PMID:7739045</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1ibg" style="background-color:#fffaf0;"></div>

==See Also==
*[[Antibody 3D structures|Antibody 3D structures]]
*[[Sandbox 20009|Sandbox 20009]]
*[[3D structures of non-human antibody|3D structures of non-human antibody]]
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Jeffrey PD]]
[[Category: Sheriff S]]