View source for 7os9


==Crystal Structure of Domain Swapped Trp Repressor V58I Variant with purification tag==
<StructureSection load='7os9' size='340' side='right'caption='[[7os9]], [[Resolution|resolution]] 2.45&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7os9]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7OS9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7OS9 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]] 2.45&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=IMD:IMIDAZOLE'>IMD</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=7os9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7os9 OCA], [https://pdbe.org/7os9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7os9 RCSB], [https://www.ebi.ac.uk/pdbsum/7os9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7os9 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/C3SE17_ECOLX C3SE17_ECOLX] This protein is an aporepressor. When complexed with L-tryptophan it binds the operator region of the trp operon (5'-ACTAGT-'3') and prevents the initiation of transcription. The complex also regulates trp repressor biosynthesis by binding to its regulatory region.[ARBA:ARBA00025375][HAMAP-Rule:MF_00475]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The crystal structures of domain-swapped tryptophan repressor (TrpR) variant Val58Ile before and after soaking with the physiological ligand L-tryptophan (L-Trp) indicate that L-Trp occupies the same location in the domain-swapped form as in native dimeric TrpR and makes equivalent residue contacts. This result is unexpected because the ligand binding-site residues arise from three separate polypeptide chains in the domain-swapped form. This work represents the first published structure of a domain-swapped form of TrpR with L-Trp bound. The presented structures also show that the protein amino-terminus, whether or not it bears a disordered extension of about 20 residues, is accessible in the large solvent channels of the domain-swapped crystal form, as in the structures reported previously in this form for TrpR without N-terminal extensions. These findings inspire the exploration of L-Trp analogs and N-terminal modifications as labels to orient guest proteins that cannot otherwise be crystallized in the solvent channels of crystalline domain-swapped TrpR hosts for potential diffraction analysis.

Crystal structures of Val58Ile tryptophan repressor in a domain-swapped array in the presence and absence of L-tryptophan.,Sprenger J, Lawson CL, von Wachenfeldt C, Lo Leggio L, Carey J Acta Crystallogr F Struct Biol Commun. 2021 Jul 1;77(Pt 7):215-225. doi:, 10.1107/S2053230X21006142. Epub 2021 Jul 30. PMID:34196612<ref>PMID:34196612</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7os9" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Carey J]]
[[Category: Lawson CL]]
[[Category: Lo Leggio L]]
[[Category: Sprenger J]]
[[Category: Von Wachenfeldt C]]