View source for 5eyp


==TUBULIN-DARPIN COMPLEX==
<StructureSection load='5eyp' size='340' side='right'caption='[[5eyp]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5eyp]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Ovis_aries Ovis aries] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5EYP OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5EYP 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]] 1.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GDP:GUANOSINE-5-DIPHOSPHATE'>GDP</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=GTP:GUANOSINE-5-TRIPHOSPHATE'>GTP</scene>, <scene name='pdbligand=LOC:N-[(7S)-1,2,3,10-TETRAMETHOXY-9-OXO-6,7-DIHYDRO-5H-BENZO[D]HEPTALEN-7-YL]ETHANAMIDE'>LOC</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=5eyp FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5eyp OCA], [https://pdbe.org/5eyp PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5eyp RCSB], [https://www.ebi.ac.uk/pdbsum/5eyp PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5eyp ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/D0VWZ0_SHEEP D0VWZ0_SHEEP] Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain (By similarity).[RuleBase:RU003505][SAAS:SAAS023123_004_019801]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Affinity maturation by random mutagenesis and selection is an established technique to make binding molecules more suitable for applications in biomedical research, diagnostics and therapy. Here we identified an unexpected novel mechanism of affinity increase upon in vitro evolution of a tubulin-specific designed ankyrin repeat protein (DARPin). Structural analysis indicated that in the progenitor DARPin the C-terminal capping repeat (C-cap) undergoes a 25 degrees rotation to avoid a clash with tubulin upon binding. Additionally, the C-cap appears to be involved in electrostatic repulsion with tubulin. Biochemical and structural characterizations demonstrated that the evolved mutants achieved a gain in affinity through destabilization of the C-cap, which relieves the need of a DARPin conformational change upon tubulin binding and removes unfavorable interactions in the complex. Therefore, this specific case of an order-to-disorder transition led to a 100-fold tighter complex with a subnanomolar equilibrium dissociation constant, remarkably associated with a 30% decrease of the binding surface.

Destabilizing an interacting motif strengthens the association of a designed ankyrin repeat protein with tubulin.,Ahmad S, Pecqueur L, Dreier B, Hamdane D, Aumont-Nicaise M, Pluckthun A, Knossow M, Gigant B Sci Rep. 2016 Jul 6;6:28922. doi: 10.1038/srep28922. PMID:27380724<ref>PMID:27380724</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5eyp" style="background-color:#fffaf0;"></div>

==See Also==
*[[Tubulin 3D Structures|Tubulin 3D Structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Ovis aries]]
[[Category: Synthetic construct]]
[[Category: Ahmad S]]
[[Category: Gigant B]]
[[Category: Knossow M]]