2a9n: Difference between revisions

From Proteopedia
Jump to navigation Jump to search
New page: left|200px<br /><applet load="2a9n" size="350" color="white" frame="true" align="right" spinBox="true" caption="2a9n, resolution 3.00Å" /> '''A Mutation Designed ...
 
No edit summary
 
(16 intermediate revisions by the same user not shown)
Line 1: Line 1:
[[Image:2a9n.gif|left|200px]]<br /><applet load="2a9n" size="350" color="white" frame="true" align="right" spinBox="true"
caption="2a9n, resolution 3.00&Aring;" />
'''A Mutation Designed to Alter Crystal Packing Permits Structural Analysis of a Tight-binding Fluorescein-scFv complex'''<br />


==Overview==
==A Mutation Designed to Alter Crystal Packing Permits Structural Analysis of a Tight-binding Fluorescein-scFv complex==
The structure of the scFv fragment FITC-E2, obtained from a naive phage, antibody scFv library derived from human donors, was determined at 2.1 A, resolution in the free form and at 3.0 A in the complexed form. The, wild-type (wt) scFv binds fluorescein with a K(D) of 0.75 nM. The free, scFv readily crystallizes by compacting its 18 amino acid-long CDR-H3, partially occluding the binding site and further blocking access by, binding to the "bottom" of a neighboring scFv molecule with a cluster of, exposed aromatic residues within CDR-H3. Only upon mutating one of the, residues involved in this dominant crystal contact, an exposed tryptophan, in the middle of CDR-H3, crystals of the complex could be obtained. A, series of alanine mutants within the putative antigen binding site, covering a range of binding affinities, were used to relate macroscopic, thermodynamic and kinetic binding parameters to single-molecule disruption, forces measured by AFM. The effects of the mutations on the binding, properties, particularly on the fraction of binding-competent molecules, within the population, cannot be fully explained by changes in the, strength of local interactions. The significant conformational change of, CDR-H3 between the free and the liganded form illustrates the plasticity, of the binding site. An accompanying study in this issue by Curcio and, colleagues presents the molecular dynamics simulation of the forced, unbinding experiments and explores possible effects of the mutations on, the unbinding pathway of the hapten.
<StructureSection load='2a9n' size='340' side='right'caption='[[2a9n]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2a9n]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2A9N OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2A9N 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]] 3&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ORE:4-(2,7-DIFLUORO-6-HYDROXY-3-OXO-3H-XANTHEN-9-YL)ISOPHTHALIC+ACID'>ORE</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=2a9n FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2a9n OCA], [https://pdbe.org/2a9n PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2a9n RCSB], [https://www.ebi.ac.uk/pdbsum/2a9n PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2a9n 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/a9/2a9n_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=2a9n ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The structure of the scFv fragment FITC-E2, obtained from a naive phage antibody scFv library derived from human donors, was determined at 2.1 A resolution in the free form and at 3.0 A in the complexed form. The wild-type (wt) scFv binds fluorescein with a K(D) of 0.75 nM. The free scFv readily crystallizes by compacting its 18 amino acid-long CDR-H3, partially occluding the binding site and further blocking access by binding to the "bottom" of a neighboring scFv molecule with a cluster of exposed aromatic residues within CDR-H3. Only upon mutating one of the residues involved in this dominant crystal contact, an exposed tryptophan in the middle of CDR-H3, crystals of the complex could be obtained. A series of alanine mutants within the putative antigen binding site, covering a range of binding affinities, were used to relate macroscopic thermodynamic and kinetic binding parameters to single-molecule disruption forces measured by AFM. The effects of the mutations on the binding properties, particularly on the fraction of binding-competent molecules within the population, cannot be fully explained by changes in the strength of local interactions. The significant conformational change of CDR-H3 between the free and the liganded form illustrates the plasticity of the binding site. An accompanying study in this issue by Curcio and colleagues presents the molecular dynamics simulation of the forced unbinding experiments and explores possible effects of the mutations on the unbinding pathway of the hapten.


==About this Structure==
A mutation designed to alter crystal packing permits structural analysis of a tight-binding fluorescein-scFv complex.,Honegger A, Spinelli S, Cambillau C, Pluckthun A Protein Sci. 2005 Oct;14(10):2537-49. PMID:16195545<ref>PMID:16195545</ref>
2A9N is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=ORE:'>ORE</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2A9N OCA].


==Reference==
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
A mutation designed to alter crystal packing permits structural analysis of a tight-binding fluorescein-scFv complex., Honegger A, Spinelli S, Cambillau C, Pluckthun A, Protein Sci. 2005 Oct;14(10):2537-49. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=16195545 16195545]
</div>
<div class="pdbe-citations 2a9n" style="background-color:#fffaf0;"></div>
 
==See Also==
*[[Antibody 3D structures|Antibody 3D structures]]
*[[Monoclonal Antibodies 3D structures|Monoclonal Antibodies 3D structures]]
*[[3D structures of human antibody|3D structures of human antibody]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Homo sapiens]]
[[Category: Single protein]]
[[Category: Large Structures]]
[[Category: Cambillau, C.]]
[[Category: Cambillau C]]
[[Category: Honegger, A.]]
[[Category: Honegger A]]
[[Category: Pluckthun, A.]]
[[Category: Pluckthun A]]
[[Category: Spinelli, S.]]
[[Category: Spinelli S]]
[[Category: ORE]]
[[Category: fluorescein]]
[[Category: immunoglobulin]]
[[Category: scfv]]
 
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jan 29 17:57:31 2008''

Latest revision as of 10:48, 30 October 2024

A Mutation Designed to Alter Crystal Packing Permits Structural Analysis of a Tight-binding Fluorescein-scFv complexA Mutation Designed to Alter Crystal Packing Permits Structural Analysis of a Tight-binding Fluorescein-scFv complex

Structural highlights

2a9n is a 2 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 3Å
Ligands:
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The structure of the scFv fragment FITC-E2, obtained from a naive phage antibody scFv library derived from human donors, was determined at 2.1 A resolution in the free form and at 3.0 A in the complexed form. The wild-type (wt) scFv binds fluorescein with a K(D) of 0.75 nM. The free scFv readily crystallizes by compacting its 18 amino acid-long CDR-H3, partially occluding the binding site and further blocking access by binding to the "bottom" of a neighboring scFv molecule with a cluster of exposed aromatic residues within CDR-H3. Only upon mutating one of the residues involved in this dominant crystal contact, an exposed tryptophan in the middle of CDR-H3, crystals of the complex could be obtained. A series of alanine mutants within the putative antigen binding site, covering a range of binding affinities, were used to relate macroscopic thermodynamic and kinetic binding parameters to single-molecule disruption forces measured by AFM. The effects of the mutations on the binding properties, particularly on the fraction of binding-competent molecules within the population, cannot be fully explained by changes in the strength of local interactions. The significant conformational change of CDR-H3 between the free and the liganded form illustrates the plasticity of the binding site. An accompanying study in this issue by Curcio and colleagues presents the molecular dynamics simulation of the forced unbinding experiments and explores possible effects of the mutations on the unbinding pathway of the hapten.

A mutation designed to alter crystal packing permits structural analysis of a tight-binding fluorescein-scFv complex.,Honegger A, Spinelli S, Cambillau C, Pluckthun A Protein Sci. 2005 Oct;14(10):2537-49. PMID:16195545[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Honegger A, Spinelli S, Cambillau C, Pluckthun A. A mutation designed to alter crystal packing permits structural analysis of a tight-binding fluorescein-scFv complex. Protein Sci. 2005 Oct;14(10):2537-49. PMID:16195545 doi:14/10/2537

2a9n, resolution 3.00Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA