View source for 2lfw


==NMR structure of the PhyRSL-NepR complex from Sphingomonas sp. Fr1==
<StructureSection load='2lfw' size='340' side='right'caption='[[2lfw]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2lfw]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Sphingomonas_sp._Fr1 Sphingomonas sp. Fr1]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LFW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2LFW FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</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=2lfw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2lfw OCA], [https://pdbe.org/2lfw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2lfw RCSB], [https://www.ebi.ac.uk/pdbsum/2lfw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2lfw ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/G8HXE0_9SPHN G8HXE0_9SPHN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Reprogramming gene expression is an essential component of adaptation to changing environmental conditions. In bacteria, a widespread mechanism involves alternative sigma factors that redirect transcription toward specific regulons. The activity of sigma factors is often regulated through sequestration by cognate anti-sigma factors; however, for most systems, it is not known how the activity of the anti-sigma factor is controlled to release the sigma factor. Recently, the general stress response sigma factor in Alphaproteobacteria, sigma(EcfG), was identified. sigma(EcfG) is inactivated by the anti-sigma factor NepR, which is itself regulated by the response regulator PhyR. This key regulator sequesters NepR upon phosphorylation of its PhyR receiver domain via its sigma(EcfG) sigma factor-like output domain (PhyR(SL)). To understand the molecular basis of the PhyR-mediated partner-switching mechanism, we solved the structure of the PhyR(SL)-NepR complex using NMR. The complex reveals an unprecedented anti-sigma factor binding mode: upon PhyR(SL) binding, NepR forms two helices that extend over the surface of the PhyR(SL) subdomains. Homology modeling and comparative analysis of NepR, PhyR(SL), and sigma(EcfG) mutants indicate that NepR contacts both proteins with the same determinants, showing sigma factor mimicry at the atomic level. A lower density of hydrophobic interactions, together with the absence of specific polar contacts in the sigma(EcfG)-NepR complex model, is consistent with the higher affinity of NepR for PhyR compared with sigma(EcfG). Finally, by reconstituting the partner switch in vitro, we demonstrate that the difference in affinity of NepR for its partners is sufficient for the switch to occur.

Structural basis for sigma factor mimicry in the general stress response of Alphaproteobacteria.,Campagne S, Damberger FF, Kaczmarczyk A, Francez-Charlot A, Allain FH, Vorholt JA Proc Natl Acad Sci U S A. 2012 May 1. PMID:22550171<ref>PMID:22550171</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2lfw" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Sphingomonas sp. Fr1]]
[[Category: Allain FH-T]]
[[Category: Campagne S]]
[[Category: Damberger FF]]
[[Category: Vorholt JA]]