View source for 4bmw


==Crystal structure of the Streptomyces reticuli HbpS E78D, E81D double mutant==
<StructureSection load='4bmw' size='340' side='right'caption='[[4bmw]], [[Resolution|resolution]] 1.99&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4bmw]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_reticuli Streptomyces reticuli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4BMW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4BMW 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]] 1.99&#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=4bmw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4bmw OCA], [https://pdbe.org/4bmw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4bmw RCSB], [https://www.ebi.ac.uk/pdbsum/4bmw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4bmw ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q9RIM2_STRRE Q9RIM2_STRRE] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The soil bacterium Streptomyces reticuli secretes the octameric protein HbpS that acts as a sensory component of the redox-signalling pathway HbpS-SenS-SenR. This system modulates a genetic response on iron- and haem-mediated oxidative stress. Moreover, HbpS alone provides this bacterium with a defence mechanism to the presence of high concentrations of iron ions and haem. While the protection against haem has been related to its haem-binding and haem-degrading activity, the interaction with iron has not been studied in detail. In this work, we biochemically analyzed the iron-binding activity of a set of generated HbpS mutant proteins and present evidence showing the involvement of one internal and two exposed D/EXXE motifs in binding of high quantities of ferrous iron, with the internal E78XXE81 displaying the tightest binding. We additionally show that HbpS is able to oxidize ferrous to ferric iron ions. Based on the crystal structure of both the wild-type and the mutant HbpS-D78XXD81, we conclude that the local arrangement of the side chains from the glutamates in E78XXE81 within the octameric assembly is a pre-requisite for interaction with iron. The data obtained led us to propose that the exposed and the internal motif build a highly specific route that is involved in the transport of high quantities of iron ions into the core of the HbpS octamer. Furthermore, physiological studies using Streptomyces transformants secreting either wild-type or HbpS mutant proteins and different redox-cycling compounds led us to conclude that the iron-sequestering activity of HbpS protects these soil bacteria from the hazardous side effects of peroxide- and iron-based oxidative stress.

Iron Binding at Specific Sites within the Octameric HbpS Protects Streptomycetes from Iron-Mediated Oxidative Stress.,Wedderhoff I, Kursula I, Groves MR, Ortiz de Orue Lucana D PLoS One. 2013 Aug 27;8(8):e71579. doi: 10.1371/journal.pone.0071579. PMID:24013686<ref>PMID:24013686</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4bmw" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptomyces reticuli]]
[[Category: Groves MR]]
[[Category: Kursula I]]
[[Category: Ortiz de Orue Lucana D]]
[[Category: Wagener S]]
[[Category: Wedderhoff I]]