View source for 6qer


==Apo Form Of ComR From S. Thermophilus in space group C2==
<StructureSection load='6qer' size='340' side='right'caption='[[6qer]], [[Resolution|resolution]] 2.46&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6qer]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptococcus_thermophilus_LMD-9 Streptococcus thermophilus LMD-9]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6QER OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6QER 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]] 2.465&#8491;</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=6qer FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6qer OCA], [https://pdbe.org/6qer PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6qer RCSB], [https://www.ebi.ac.uk/pdbsum/6qer PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6qer ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A1L1QK15_STRTD A0A1L1QK15_STRTD] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Competence allows bacteria to internalize exogenous DNA fragments for the acquisition of new phenotypes such as antibiotic resistance or virulence traits. In most streptococci, competence is regulated by ComRS signaling, a system based on the mature ComS pheromone (XIP), which is internalized to activate the (R)RNPP-type ComR sensor by triggering dimerization and DNA binding. Cross-talk analyses demonstrated major differences of selectivity between ComRS systems and raised questions concerning the mechanism of pheromone-sensor recognition and coevolution. Here, we decipher the molecular determinants of selectivity of the closely related ComRS systems from Streptococcus thermophilus and Streptococcus vestibularis Despite high similarity, we show that the divergence in ComR-XIP interaction does not allow reciprocal activation. We perform the structural analysis of the ComRS system from S. vestibularis. Comparison with its ortholog from S. thermophilus reveals an activation mechanism based on a toggle switch involving the recruitment of a key loop by the XIP C terminus. Together with a broad mutational analysis, we identify essential residues directly involved in peptide binding. Notably, we generate a ComR mutant that displays a fully reversed selectivity toward the heterologous pheromone with only five point mutations, as well as other ComR variants featuring XIP bispecificity and/or neofunctionalization for hybrid XIP peptides. We also reveal that a single XIP mutation relaxes the strictness of ComR activation, suggesting fast adaptability of molecular communication phenotypes. Overall, this study is paving the way toward the rational design or directed evolution of artificial ComRS systems for a range of biotechnological and biomedical applications.

Molecular dissection of pheromone selectivity in the competence signaling system ComRS of streptococci.,Ledesma-Garcia L, Thuillier J, Guzman-Espinola A, Ensinck I, Li de la Sierra-Gallay I, Lazar N, Aumont-Nicaise M, Mignolet J, Soumillion P, Nessler S, Hols P Proc Natl Acad Sci U S A. 2020 Mar 20. pii: 1916085117. doi:, 10.1073/pnas.1916085117. PMID:32198205<ref>PMID:32198205</ref>

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

==See Also==
*[[Transcriptional activator 3D structures|Transcriptional activator 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptococcus thermophilus LMD-9]]
[[Category: Nessler S]]
[[Category: Thuillier J]]