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4bx6
From Proteopedia
(Difference between revisions)
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| - | + | ==trans-divalent streptavidin== | |
| - | === | + | <StructureSection load='4bx6' size='340' side='right' caption='[[4bx6]], [[Resolution|resolution]] 1.59Å' scene=''> |
| - | + | == Structural highlights == | |
| - | + | <table><tr><td colspan='2'>[[4bx6]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/As_4.1583 As 4.1583]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4BX6 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4BX6 FirstGlance]. <br> | |
| - | ==Function== | + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</scene></td></tr> |
| + | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4bx5|4bx5]], [[4bx7|4bx7]]</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=4bx6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4bx6 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4bx6 RCSB], [http://www.ebi.ac.uk/pdbsum/4bx6 PDBsum]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
[[http://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). | [[http://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). | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == 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> | |
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
[[Category: As 4 1583]] | [[Category: As 4 1583]] | ||
| - | [[Category: Fairhead, M | + | [[Category: Fairhead, M]] |
| - | [[Category: Howarth, M | + | [[Category: Howarth, M]] |
| - | [[Category: Krndija, D | + | [[Category: Krndija, D]] |
| - | [[Category: Lowe, E D | + | [[Category: Lowe, E D]] |
[[Category: Avidin]] | [[Category: Avidin]] | ||
[[Category: Biotin-binding protein]] | [[Category: Biotin-binding protein]] | ||
Revision as of 21:40, 25 December 2014
trans-divalent streptavidin
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