View source for 3qhf

==Crystal Structure of Fab del2D1, a deletion variant of anti-influenza antibody 2D1==
<StructureSection load='3qhf' size='340' side='right' caption='[[3qhf]], [[Resolution|resolution]] 1.66&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3qhf]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3QHF OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3QHF FirstGlance]. <br>
</td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3qhz|3qhz]]</td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">Immunoglobulin gamma ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]), Immunoglobulin lambda ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens])</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3qhf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3qhf OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3qhf RCSB], [http://www.ebi.ac.uk/pdbsum/3qhf PDBsum]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The structural and functional significance of somatic insertions and deletions in antibody chains is unclear. Here, we demonstrate that a naturally occurring three-amino-acid insertion within the influenza virus-specific human monoclonal antibody 2D1 heavy-chain variable region reconfigures the antibody-combining site and contributes to its high potency against the 1918 and 2009 pandemic H1N1 influenza viruses. The insertion arose through a series of events, including a somatic point mutation in a predicted hot-spot motif, introduction of a new hot-spot motif, a molecular duplication due to polymerase slippage, a deletion due to misalignment, and additional somatic point mutations. Atomic resolution structures of the wild-type antibody and a variant in which the insertion was removed revealed that the three-amino-acid insertion near the base of heavy-chain complementarity-determining region (CDR) H2 resulted in a bulge in that loop. This enlarged CDR H2 loop impinges on adjacent regions, causing distortion of the CDR H1 architecture and its displacement away from the antigen-combining site. Removal of the insertion restores the canonical structure of CDR H1 and CDR H2, but binding, neutralization activity, and in vivo activity were reduced markedly because of steric conflict of CDR H1 with the hemagglutinin antigen.

An insertion mutation that distorts antibody binding site architecture enhances function of a human antibody.,Krause JC, Ekiert DC, Tumpey TM, Smith PB, Wilson IA, Crowe JE Jr MBio. 2011 Feb 8;2(1):e00345-10. doi: 10.1128/mBio.00345-10. Print 2011. PMID:21304166<ref>PMID:21304166</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>

==See Also==
*[[Monoclonal Antibody|Monoclonal Antibody]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Ekiert, D C]]
[[Category: Wilson, I A]]
[[Category: Immune recognition]]
[[Category: Immune system]]
[[Category: Immunoglobulin]]
[[Category: Influenza a virus hemagglutinin]]