4bx7: Difference between revisions
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== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[4bx7]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_avidinii Streptomyces avidinii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4BX7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4BX7 FirstGlance]. <br> | <table><tr><td colspan='2'>[[4bx7]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_avidinii Streptomyces avidinii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4BX7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4BX7 FirstGlance]. <br> | ||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=B4F:BIOTIN-4-FLUORESCEIN'>B4F</scene>, <scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</scene></td></tr> | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.26Å</td></tr> | ||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=B4F:BIOTIN-4-FLUORESCEIN'>B4F</scene>, <scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</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=4bx7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4bx7 OCA], [https://pdbe.org/4bx7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4bx7 RCSB], [https://www.ebi.ac.uk/pdbsum/4bx7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4bx7 ProSAT]</span></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=4bx7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4bx7 OCA], [https://pdbe.org/4bx7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4bx7 RCSB], [https://www.ebi.ac.uk/pdbsum/4bx7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4bx7 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[https://www.uniprot.org/uniprot/SAV_STRAV SAV_STRAV] The biological function of streptavidin is not known. Forms a strong non-covalent specific complex with biotin (one molecule of biotin per subunit of streptavidin). | |||
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== Publication Abstract from PubMed == | |||
Streptavidin is one of the most important hubs for molecular biology, either multimerizing biomolecules, bridging one molecule to another, or anchoring to a biotinylated surface/nanoparticle. Streptavidin has the advantage of rapid ultra-stable binding to biotin. However, the ability of streptavidin to bind four biotinylated molecules in a heterogeneous manner is often limiting. Here, we present an efficient approach to isolate streptavidin tetramers with two biotin-binding sites in a precise arrangement, cis or trans. We genetically modified specific subunits with negatively charged tags, refolded a mixture of monomers, and used ion-exchange chromatography to resolve tetramers according to the number and orientation of tags. We solved the crystal structures of cis-divalent streptavidin to 1.4A resolution and trans-divalent streptavidin to 1.6A resolution, validating the isolation strategy and explaining the behavior of the Dead streptavidin variant. cis- and trans-divalent streptavidins retained tetravalent streptavidin's high thermostability and low off-rate. These defined divalent streptavidins enabled us to uncover how streptavidin binding depends on the nature of the biotin ligand. Biotinylated DNA showed strong negative cooperativity of binding to cis-divalent but not trans-divalent streptavidin. A small biotinylated protein bound readily to cis and trans binding sites. We also solved the structure of trans-divalent streptavidin bound to biotin-4-fluorescein, showing how one ligand obstructs binding to an adjacent biotin-binding site. Using a hexaglutamate tag proved a more powerful way to isolate monovalent streptavidin, for ultra-stable labeling without undesired clustering. These forms of streptavidin allow this key hub to be used with a new level of precision, for homogeneous molecular assembly. | |||
Plug-and-Play Pairing via Defined Divalent Streptavidins.,Fairhead M, Krndija D, Lowe ED, Howarth M J Mol Biol. 2013 Sep 19. pii: S0022-2836(13)00600-1. doi:, 10.1016/j.jmb.2013.09.016. PMID:24056174<ref>PMID:24056174</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 4bx7" style="background-color:#fffaf0;"></div> | |||
==See Also== | ==See Also== | ||
*[[Avidin 3D structures|Avidin 3D structures]] | *[[Avidin 3D structures|Avidin 3D structures]] | ||
== References == | |||
<references/> | |||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||