View source for 4j7c


==KtrAB potassium transporter from Bacillus subtilis==
<StructureSection load='4j7c' size='340' side='right'caption='[[4j7c]], [[Resolution|resolution]] 3.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4j7c]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Bacillus_subtilis_subsp._subtilis_str._168 Bacillus subtilis subsp. subtilis str. 168]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4J7C OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4J7C 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]] 3.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</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=4j7c FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4j7c OCA], [https://pdbe.org/4j7c PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4j7c RCSB], [https://www.ebi.ac.uk/pdbsum/4j7c PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4j7c ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/KTRA_BACSU KTRA_BACSU] Catalytic subunit of the KtrAB potassium uptake transporter. The 2 major potassium transporter complexes KtrAB and KtrCD confer resistance to both suddenly imposed and prolonged osmotic stress.<ref>PMID:12562800</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
In bacteria, archaea, fungi and plants the Trk, Ktr and HKT ion transporters are key components of osmotic regulation, pH homeostasis and resistance to drought and high salinity. These ion transporters are functionally diverse: they can function as Na(+) or K(+) channels and possibly as cation/K(+) symporters. They are closely related to potassium channels both at the level of the membrane protein and at the level of the cytosolic regulatory domains. Here we describe the crystal structure of a Ktr K(+) transporter, the KtrAB complex from Bacillus subtilis. The structure shows the dimeric membrane protein KtrB assembled with a cytosolic octameric KtrA ring bound to ATP, an activating ligand. A comparison between the structure of KtrAB-ATP and the structures of the isolated full-length KtrA protein with ATP or ADP reveals a ligand-dependent conformational change in the octameric ring, raising new ideas about the mechanism of activation in these transporters.

The structure of the KtrAB potassium transporter.,Vieira-Pires RS, Szollosi A, Morais-Cabral JH Nature. 2013 Apr 18;496(7445):323-8. doi: 10.1038/nature12055. PMID:23598340<ref>PMID:23598340</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4j7c" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Bacillus subtilis subsp. subtilis str. 168]]
[[Category: Large Structures]]
[[Category: Morais-Cabral JH]]
[[Category: Vieira-Pires RS]]