View source for 4u46


==Crystal structure of an avidin mutant==
<StructureSection load='4u46' size='340' side='right'caption='[[4u46]], [[Resolution|resolution]] 1.95&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4u46]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4U46 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4U46 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]] 1.95&#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></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=4u46 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4u46 OCA], [https://pdbe.org/4u46 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4u46 RCSB], [https://www.ebi.ac.uk/pdbsum/4u46 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4u46 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/AVID_CHICK AVID_CHICK] The biological function of avidin is not known. Forms a strong non-covalent specific complex with biotin (one molecule of biotin per subunit of avidin).
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Proteins with high specificity, affinity, and stability are needed for biomolecular recognition in a plethora of applications. Antibodies are powerful affinity tools, but they may also suffer from limitations such as low stability and high production costs. Avidin and streptavidin provide a promising scaffold for protein engineering, and due to their ultratight binding to D-biotin they are widely used in various biotechnological and biomedical applications. In this study, we demonstrate that the avidin scaffold is suitable for use as a novel receptor for several biologically active small molecules: Artificial, chicken avidin-based proteins, antidins, were generated using a directed evolution method for progesterone, hydrocortisone, testosterone, cholic acid, ketoprofen, and folic acid, all with micromolar to nanomolar affinity and significantly reduced biotin-binding affinity. We also describe the crystal structure of an antidin, sbAvd-2(I117Y), a steroid-binding avidin, which proves that the avidin scaffold can tolerate significant modifications without losing its characteristic tetrameric beta-barrel structure, helping us to further design avidin-based small molecule receptors.

Artificial Avidin-Based Receptors for a Panel of Small Molecules.,Lehtonen SI, Tullila A, Agrawal N, Kukkurainen S, Kahkonen N, Koskinen M, Nevanen TK, Johnson MS, Airenne TT, Kulomaa MS, Riihimaki TA, Hytonen VP ACS Chem Biol. 2016 Jan 15;11(1):211-21. doi: 10.1021/acschembio.5b00906. Epub, 2015 Nov 23. PMID:26550684<ref>PMID:26550684</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4u46" style="background-color:#fffaf0;"></div>

==See Also==
*[[Avidin 3D structures|Avidin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Gallus gallus]]
[[Category: Large Structures]]
[[Category: Agrawal N]]
[[Category: Airenne TT]]
[[Category: Hytonen VP]]
[[Category: Johnson MS]]
[[Category: Kahkonen N]]
[[Category: Kulomaa MS]]
[[Category: Lehtonen S]]
[[Category: Riihimaki T]]