1frg

<StructureSection load='1frg' size='340' side='right' caption='[[1frg]], [[Resolution|resolution]] 2.80&Aring;' scene=''>

<table><tr><td colspan='2'>[[1frg]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Lk3_transgenic_mice Lk3 transgenic mice]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1FRG OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1FRG FirstGlance]. <br>

</td></tr><tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=ACE:ACETYL+GROUP'>ACE</scene>, <scene name='pdbligand=NH2:AMINO+GROUP'>NH2</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1him|1him]], [[1hin|1hin]], [[1ifh|1ifh]]</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=1frg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1frg OCA], [http://pdbe.org/1frg PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1frg RCSB], [http://www.ebi.ac.uk/pdbsum/1frg PDBsum]</span></td></tr>

<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fr/1frg_consurf.spt"</scriptWhenChecked>

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== Publication Abstract from PubMed ==

The three-dimensional structure of the complex of a second anti-peptide antibody (Fab 26/9) that recognizes the same six-residue epitope of an immunogenic peptide from influenza virus hemagglutinin (HA1; 75-110) as Fab 17/9 with the peptide has been determined at 2.8 A resolution. The amino acid sequence of the variable region of the 26/9 antibody differs in 24 positions from that of 17/9, the first antibody in this series for which several ligand-bound and free structures have been determined and refined. Comparison of the 26/9-peptide with the 17/9-peptide complex structures shows that the two Fabs are very similar (r.m.s.d. 0.5 to 0.8 A) and that the peptide antigen (101-107) has virtually the same conformation (r.m.s.d. 0.3 to 0.8 A) when bound to both antibodies. A sequence difference in the 26/9 binding pocket (L94; His in 26/9, Asn in 17/9) results in an interaction with a bound water molecule that is not seen in the 17/9 structures. Epitope mapping shows that the relative specificity of 26/9 and 17/9 antibodies for individual positions of the peptide antigen are slightly different. Amino acid substitutions in the peptide, particularly at position SerP107, are tolerated to different extents by 17/9 and 26/9. Structural and sequence analysis suggests that amino acid differences near the peptide-binding site are responsible for altering slightly the specificity of 26/9 for three peptide residues and illustrates how amino acid substitutions can modify antibody-antigen interactions and thereby modulate antibody specificity.

Crystal structure of a peptide complex of anti-influenza peptide antibody Fab 26/9. Comparison of two different antibodies bound to the same peptide antigen.,Churchill ME, Stura EA, Pinilla C, Appel JR, Houghten RA, Kono DH, Balderas RS, Fieser GG, Schulze-Gahmen U, Wilson IA J Mol Biol. 1994 Aug 26;241(4):534-56. PMID:7520084<ref>PMID:7520084</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 1frg" style="background-color:#fffaf0;"></div>

*[[Antibody|Antibody]]

[[Category: Lk3 transgenic mice]]

[[Category: Churchill, M E.A]]

[[Category: Wilson, I A]]

[[Category: Immunoglobulin/virus hemagglutinin]]

[[Category: Viral protein-immune system complex]]