View source for 6g87


==Flavonoid-responsive Regulator FrrA==
<StructureSection load='6g87' size='340' side='right'caption='[[6g87]], [[Resolution|resolution]] 2.92&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6g87]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/3i1b110 3i1b110]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6G87 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6G87 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NHE:2-[N-CYCLOHEXYLAMINO]ETHANE+SULFONIC+ACID'>NHE</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">CO678_15510 ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1355477 3I1B110])</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=6g87 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6g87 OCA], [https://pdbe.org/6g87 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6g87 RCSB], [https://www.ebi.ac.uk/pdbsum/6g87 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6g87 ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Bradyrhizobium diazoefficiens, a bacterial symbiont of soybean and other leguminous plants, enters a nodulation-promoting genetic programme in the presence of host-produced flavonoids and related signalling compounds. Here, we describe the crystal structure of an isoflavonoid-responsive regulator (FrrA) from Bradyrhizobium, as well as cocrystal structures with inducing and noninducing ligands (genistein and naringenin, respectively). The structures reveal a TetR-like fold whose DNA-binding domain is capable of adopting a range of orientations. A single molecule of either genistein or naringenin is asymmetrically bound in a central cavity of the FrrA homodimer, mainly via C-H contacts to the pi-system of the ligands. Strikingly, however, the interaction does not provoke any conformational changes in the repressor. Both the flexible positioning of the DNA-binding domain and the absence of structural change upon ligand binding are corroborated by small-angle X-ray scattering (SAXS) experiments in solution. Together with a model of the promoter-bound state of FrrA our results suggest that inducers act as a wedge, preventing the DNA-binding domains from moving close enough together to interact with successive positions of the major groove of the palindromic operator.

The induction mechanism of the flavonoid-responsive regulator FrrA.,Werner N, Werten S, Hoppen J, Palm GJ, Gottfert M, Hinrichs W FEBS J. 2021 Jul 27. doi: 10.1111/febs.16141. PMID:34314575<ref>PMID:34314575</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6g87" style="background-color:#fffaf0;"></div>

==See Also==
*[[Tetracycline repressor protein 3D structures|Tetracycline repressor protein 3D structures]]
*[[Transcriptional activator 3D structures|Transcriptional activator 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Goettfert, M]]
[[Category: Hinrichs, W]]
[[Category: Hoppen, J]]
[[Category: Palm, G]]
[[Category: Werner, N]]
[[Category: Werten, S]]
[[Category: Flavonoid]]
[[Category: Repressor]]
[[Category: Tetr-family]]
[[Category: Transcription]]