|
|
| Line 3: |
Line 3: |
| | <StructureSection load='6i8v' size='340' side='right'caption='[[6i8v]], [[Resolution|resolution]] 1.99Å' scene=''> | | <StructureSection load='6i8v' size='340' side='right'caption='[[6i8v]], [[Resolution|resolution]] 1.99Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[6i8v]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6I8V OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6I8V FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[6i8v]] is a 1 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=6I8V OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6I8V FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=BU1:1,4-BUTANEDIOL'>BU1</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.991Å</td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6i8v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6i8v OCA], [http://pdbe.org/6i8v PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6i8v RCSB], [http://www.ebi.ac.uk/pdbsum/6i8v PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6i8v ProSAT]</span></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=BU1:1,4-BUTANEDIOL'>BU1</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</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=6i8v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6i8v OCA], [https://pdbe.org/6i8v PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6i8v RCSB], [https://www.ebi.ac.uk/pdbsum/6i8v PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6i8v ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/KTRC_BACSU KTRC_BACSU]] Catalytic subunit of the KtrCD 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> | + | [https://www.uniprot.org/uniprot/KTRC_BACSU KTRC_BACSU] Catalytic subunit of the KtrCD 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;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
| Line 22: |
Line 23: |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| | + | [[Category: Bacillus subtilis subsp. subtilis str. 168]] |
| | [[Category: Large Structures]] | | [[Category: Large Structures]] |
| - | [[Category: Morais-Cabral, J H]] | + | [[Category: Morais-Cabral JH]] |
| - | [[Category: Rocha, R]] | + | [[Category: Rocha R]] |
| - | [[Category: Ion transport]]
| + | |
| - | [[Category: Metal transport]]
| + | |
| Structural highlights
Function
KTRC_BACSU Catalytic subunit of the KtrCD potassium uptake transporter. The 2 major potassium transporter complexes KtrAB and KtrCD confer resistance to both suddenly imposed and prolonged osmotic stress.[1]
Publication Abstract from PubMed
RCK (regulating conductance of K(+)) domains are common regulatory domains that control the activity of eukaryotic and prokaryotic K(+) channels and transporters. In bacteria these domains play roles in osmoregulation, regulation of turgor and membrane potential and in pH homeostasis. Whole-genome sequencing unveiled RCK gene redundancy, however the biological role of this redundancy is not well understood. In Bacillus subtilis, there are two closely related RCK domain proteins (KtrA and KtrC) that regulate the activity of the Ktr cation channels. KtrA has been well characterized but little is known about KtrC. We have characterized the structural and biochemical proprieties of KtrC and conclude that KtrC binds ATP and ADP, just like KtrA. However, in solution KtrC exist in a dynamic equilibrium between octamers and non-octameric species that is dependent on the bound ligand, with ATP destabilizing the octameric ring relative to ADP. Accordingly, KtrC-ADP crystal structures reveal closed octameric rings similar to those in KtrA, while KtrC-ATP adopts an open assembly with RCK domains forming a super-helix. In addition, both KtrC-ATP and -ADP octamers are stabilized by the signaling molecule cyclic-di-AMP, which binds to KtrC with high affinity. In contrast, c-di-AMP binds with 100-fold lower affinity to KtrA. Despite these differences we show with an E. coli complementation assay that KtrC and KtrA are interchangeable and able to form functional transporters with both KtrB and KtrD. The distinctive properties of KtrC, in particular ligand-dependent assembly/disassembly, suggest that this protein has a specific physiological role that is distinct from KtrA.
Characterization of the molecular properties of KtrC, a second RCK domain that regulates a Ktr channel in Bacillus subtilis.,Rocha R, Teixeira-Duarte CM, Jorge JMP, Morais-Cabral JH J Struct Biol. 2019 Mar 1;205(3):34-43. doi: 10.1016/j.jsb.2019.02.002. Epub 2019, Feb 10. PMID:30753894[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Holtmann G, Bakker EP, Uozumi N, Bremer E. KtrAB and KtrCD: two K+ uptake systems in Bacillus subtilis and their role in adaptation to hypertonicity. J Bacteriol. 2003 Feb;185(4):1289-98. PMID:12562800
- ↑ Rocha R, Teixeira-Duarte CM, Jorge JMP, Morais-Cabral JH. Characterization of the molecular properties of KtrC, a second RCK domain that regulates a Ktr channel in Bacillus subtilis. J Struct Biol. 2019 Mar 1;205(3):34-43. doi: 10.1016/j.jsb.2019.02.002. Epub 2019, Feb 10. PMID:30753894 doi:http://dx.doi.org/10.1016/j.jsb.2019.02.002
|
