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| | <StructureSection load='4gd9' size='340' side='right'caption='[[4gd9]], [[Resolution|resolution]] 1.50Å' scene=''> | | <StructureSection load='4gd9' size='340' side='right'caption='[[4gd9]], [[Resolution|resolution]] 1.50Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[4gd9]] 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=4GD9 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4GD9 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[4gd9]] is a 4 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=4GD9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4GD9 FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=BTN:BIOTIN'>BTN</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> | + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BTN:BIOTIN'>BTN</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1swf|1swf]]</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=4gd9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gd9 OCA], [https://pdbe.org/4gd9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4gd9 RCSB], [https://www.ebi.ac.uk/pdbsum/4gd9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4gd9 ProSAT]</span></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=4gd9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4gd9 OCA], [http://pdbe.org/4gd9 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4gd9 RCSB], [http://www.ebi.ac.uk/pdbsum/4gd9 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4gd9 ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == 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). | + | [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). |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: As 4 1583]] | |
| | [[Category: Large Structures]] | | [[Category: Large Structures]] |
| - | [[Category: Chu, V]] | + | [[Category: Streptomyces avidinii]] |
| - | [[Category: Lybrand, T P]] | + | [[Category: Chu V]] |
| - | [[Category: Stayton, P S]]
| + | [[Category: Le Trong I]] |
| - | [[Category: Stenkamp, R E]]
| + | [[Category: Lybrand TP]] |
| - | [[Category: Trong, I Le]] | + | [[Category: Stayton PS]] |
| - | [[Category: Xing, Y]] | + | [[Category: Stenkamp RE]] |
| - | [[Category: Biotin]] | + | [[Category: Xing Y]] |
| - | [[Category: Biotin-binding protein]] | + | |
| - | [[Category: Circular permutation]] | + | |
| Structural highlights
Function
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).
Publication Abstract from PubMed
Circular permutation of streptavidin was carried out in order to investigate the role of a main-chain amide in stabilizing the high-affinity complex of the protein and biotin. Mutant proteins CP49/48 and CP50/49 were constructed to place new N-termini at residues 49 and 50 in a flexible loop involved in stabilizing the biotin complex. Crystal structures of the two mutants show that half of each loop closes over the binding site, as observed in wild-type streptavidin, while the other half adopts the open conformation found in the unliganded state. The structures are consistent with kinetic and thermodynamic data and indicate that the loop plays a role in enthalpic stabilization of the bound state via the Asn49 amide-biotin hydrogen bond. In wild-type streptavidin, the entropic penalties of immobilizing a flexible portion of the protein to enhance binding are kept to a manageable level by using a contiguous loop of medium length (six residues) which is already constrained by its anchorage to strands of the beta-barrel protein. A molecular-dynamics simulation for CP50/49 shows that cleavage of the binding loop results in increased structural fluctuations for Ser45 and that these fluctuations destabilize the streptavidin-biotin complex.
Structural consequences of cutting a binding loop: two circularly permuted variants of streptavidin.,Le Trong I, Chu V, Xing Y, Lybrand TP, Stayton PS, Stenkamp RE Acta Crystallogr D Biol Crystallogr. 2013 Jun;69(Pt 6):968-77. doi:, 10.1107/S0907444913003855. Epub 2013 May 11. PMID:23695241[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Le Trong I, Chu V, Xing Y, Lybrand TP, Stayton PS, Stenkamp RE. Structural consequences of cutting a binding loop: two circularly permuted variants of streptavidin. Acta Crystallogr D Biol Crystallogr. 2013 Jun;69(Pt 6):968-77. doi:, 10.1107/S0907444913003855. Epub 2013 May 11. PMID:23695241 doi:10.1107/S0907444913003855
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