View source for 2xiw


==Crystal structure of the Sac7d-derived IgG1-binder C3-C24S==
<StructureSection load='2xiw' size='340' side='right'caption='[[2xiw]], [[Resolution|resolution]] 1.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2xiw]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Sulfolobus_acidocaldarius Sulfolobus acidocaldarius]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2XIW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2XIW 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]] 1.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=2xiw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2xiw OCA], [https://pdbe.org/2xiw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2xiw RCSB], [https://www.ebi.ac.uk/pdbsum/2xiw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2xiw ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DN7D_SULAC DN7D_SULAC] Can constrain negative DNA supercoils. May be involved in maintaining the integrity of the genome at high temperature.[UniProtKB:P61990]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Engineered protein scaffolds have received considerable attention as alternatives to antibodies in both basic and applied research, as they can offer superior biophysical properties often associated with a simpler molecular organization. Sac7d has been demonstrated as an effective scaffold for molecular recognition. Here, we used the initial L1 'flat surface' library constructed by randomization of 14 residues, to identify ligands specific for human immunoglobulin G. To challenge the plasticity of the Sac7d protein scaffold, we designed the alternative L2 'flat surface &amp; loops' library whereof only 10 residues are randomized. Representative binders (Affitins) of the two libraries exhibited affinities in the low nanomolar range and were able to recognize different epitopes within human immunoglobulin G. These Affitins were stable up to pH 12 while largely conserving other favorable properties of Sac7d protein, such as high expression yields in Escherichia coli, solubility, thermal stability up to 80.7 degrees C, and acidic stability (pH 0). In agreement with our library designs, mutagenesis study revealed two distinct binding areas, one including loops. Together, our results indicate that the Sac7d scaffold tolerates alternative library designs, which further expands the diversity of Affitins and may provide a general way to create tailored affinity tools for demanding applications.

Tolerance of the archaeal Sac7d scaffold protein to alternative library designs: characterization of anti-immunoglobulin G Affitins.,Behar G, Bellinzoni M, Maillasson M, Paillard-Laurance L, Alzari PM, He X, Mouratou B, Pecorari F Protein Eng Des Sel. 2013 Jan 11. PMID:23315487<ref>PMID:23315487</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2xiw" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Sulfolobus acidocaldarius]]
[[Category: Alzari PM]]
[[Category: Behar G]]
[[Category: Bellinzoni M]]
[[Category: Colinet S]]
[[Category: Pecorari F]]