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| | ==Structure of the KdpFABC complex== | | ==Structure of the KdpFABC complex== |
| - | <StructureSection load='5mrw' size='340' side='right' caption='[[5mrw]], [[Resolution|resolution]] 2.90Å' scene=''> | + | <StructureSection load='5mrw' size='340' side='right'caption='[[5mrw]], [[Resolution|resolution]] 2.90Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[5mrw]] is a 12 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5MRW OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5MRW FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[5mrw]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5MRW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5MRW FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=BOG:B-OCTYLGLUCOSIDE'>BOG</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=PX4:1,2-DIMYRISTOYL-SN-GLYCERO-3-PHOSPHOCHOLINE'>PX4</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]] 2.9Å</td></tr> |
| - | <tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=SEP:PHOSPHOSERINE'>SEP</scene></td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BOG:B-OCTYLGLUCOSIDE'>BOG</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=PX4:1,2-DIMYRISTOYL-SN-GLYCERO-3-PHOSPHOCHOLINE'>PX4</scene>, <scene name='pdbligand=SEP:PHOSPHOSERINE'>SEP</scene></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">kdpA, b0698, JW0686 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895]), kdpB, b0697, JW0685 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895]), kdpC, JD73_10370 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895]), kdpF, b4513, JW0687 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895])</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=5mrw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5mrw OCA], [https://pdbe.org/5mrw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5mrw RCSB], [https://www.ebi.ac.uk/pdbsum/5mrw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5mrw ProSAT]</span></td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Potassium-transporting_ATPase Potassium-transporting ATPase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.3.12 3.6.3.12] </span></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=5mrw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5mrw OCA], [http://pdbe.org/5mrw PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5mrw RCSB], [http://www.ebi.ac.uk/pdbsum/5mrw PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5mrw ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/KDPF_ECOLI KDPF_ECOLI]] Part of the high-affinity ATP-driven potassium transport (or Kdp) system, which catalyzes the hydrolysis of ATP coupled with the electrogenic transport of potassium into the cytoplasm (PubMed:23930894). This subunit may be involved in stabilization of the complex (PubMed:10608856).<ref>PMID:10608856</ref> <ref>PMID:23930894</ref> [[http://www.uniprot.org/uniprot/KDPA_ECOLI KDPA_ECOLI]] Part of the high-affinity ATP-driven potassium transport (or Kdp) system, which catalyzes the hydrolysis of ATP coupled with the electrogenic transport of potassium into the cytoplasm (PubMed:2849541, PubMed:8499455, PubMed:23930894). This subunit binds and transports the potassium across the cytoplasmic membrane (PubMed:7896809).<ref>PMID:23930894</ref> <ref>PMID:2849541</ref> <ref>PMID:7896809</ref> <ref>PMID:8499455</ref> [[http://www.uniprot.org/uniprot/A0A085P4P2_ECOLX A0A085P4P2_ECOLX]] Part of the high-affinity ATP-driven potassium transport (or Kdp) system, which catalyzes the hydrolysis of ATP coupled with the electrogenic transport of potassium into the cytoplasm. This subunit acts as a catalytic chaperone that increases the ATP-binding affinity of the ATP-hydrolyzing subunit KdpB by the formation of a transient KdpB/KdpC/ATP ternary complex.[HAMAP-Rule:MF_00276][SAAS:SAAS00702316] [[http://www.uniprot.org/uniprot/KDPB_ECOLI KDPB_ECOLI]] Part of the high-affinity ATP-driven potassium transport (or Kdp) system, which catalyzes the hydrolysis of ATP coupled with the electrogenic transport of potassium into the cytoplasm (PubMed:2849541, PubMed:8499455, PubMed:23930894). This subunit is responsible for energy coupling to the transport system (PubMed:16354672).<ref>PMID:16354672</ref> <ref>PMID:23930894</ref> <ref>PMID:2849541</ref> <ref>PMID:8499455</ref> | + | [https://www.uniprot.org/uniprot/KDPA_ECOLI KDPA_ECOLI] Part of the high-affinity ATP-driven potassium transport (or Kdp) system, which catalyzes the hydrolysis of ATP coupled with the electrogenic transport of potassium into the cytoplasm (PubMed:2849541, PubMed:8499455, PubMed:23930894). This subunit binds and transports the potassium across the cytoplasmic membrane (PubMed:7896809).<ref>PMID:23930894</ref> <ref>PMID:2849541</ref> <ref>PMID:7896809</ref> <ref>PMID:8499455</ref> |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Bacillus coli migula 1895]] | + | [[Category: Escherichia coli]] |
| - | [[Category: Potassium-transporting ATPase]] | + | [[Category: Large Structures]] |
| - | [[Category: Huang, C]] | + | [[Category: Huang C]] |
| - | [[Category: Pedersen, B P]] | + | [[Category: Pedersen BP]] |
| - | [[Category: Stokes, D L]] | + | [[Category: Stokes DL]] |
| - | [[Category: Hydrolase]]
| + | |
| - | [[Category: Membrane protein complex potassium transport p-type atpase skt channel]]
| + | |
| Structural highlights
Function
KDPA_ECOLI Part of the high-affinity ATP-driven potassium transport (or Kdp) system, which catalyzes the hydrolysis of ATP coupled with the electrogenic transport of potassium into the cytoplasm (PubMed:2849541, PubMed:8499455, PubMed:23930894). This subunit binds and transports the potassium across the cytoplasmic membrane (PubMed:7896809).[1] [2] [3] [4]
Publication Abstract from PubMed
Cellular potassium import systems play a fundamental role in osmoregulation, pH homeostasis and membrane potential in all domains of life. In bacteria, the kdp operon encodes a four-subunit potassium pump that maintains intracellular homeostasis, cell shape and turgor under conditions in which potassium is limiting. This membrane complex, called KdpFABC, has one channel-like subunit (KdpA) belonging to the superfamily of potassium transporters and another pump-like subunit (KdpB) belonging to the superfamily of P-type ATPases. Although there is considerable structural and functional information about members of both superfamilies, the mechanism by which uphill potassium transport through KdpA is coupled with ATP hydrolysis by KdpB remains poorly understood. Here we report the 2.9 A X-ray structure of the complete Escherichia coli KdpFABC complex with a potassium ion within the selectivity filter of KdpA and a water molecule at a canonical cation site in the transmembrane domain of KdpB. The structure also reveals two structural elements that appear to mediate the coupling between these two subunits. Specifically, a protein-embedded tunnel runs between these potassium and water sites and a helix controlling the cytoplasmic gate of KdpA is linked to the phosphorylation domain of KdpB. On the basis of these observations, we propose a mechanism that repurposes protein channel architecture for active transport across biomembranes.
Crystal structure of the potassium-importing KdpFABC membrane complex.,Huang CS, Pedersen BP, Stokes DL Nature. 2017 Jun 29;546(7660):681-685. doi: 10.1038/nature22970. Epub 2017 Jun, 21. PMID:28636601[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Damnjanovic B, Weber A, Potschies M, Greie JC, Apell HJ. Mechanistic analysis of the pump cycle of the KdpFABC P-type ATPase. Biochemistry. 2013 Aug 20;52(33):5563-76. doi: 10.1021/bi400729e. Epub 2013 Aug, 9. PMID:23930894 doi:http://dx.doi.org/10.1021/bi400729e
- ↑ Siebers A, Altendorf K. The K+-translocating Kdp-ATPase from Escherichia coli. Purification, enzymatic properties and production of complex- and subunit-specific antisera. Eur J Biochem. 1988 Dec 1;178(1):131-40. PMID:2849541
- ↑ Buurman ET, Kim KT, Epstein W. Genetic evidence for two sequentially occupied K+ binding sites in the Kdp transport ATPase. J Biol Chem. 1995 Mar 24;270(12):6678-85. PMID:7896809
- ↑ Kollmann R, Altendorf K. ATP-driven potassium transport in right-side-out membrane vesicles via the Kdp system of Escherichia coli. Biochim Biophys Acta. 1993 Jun 10;1143(1):62-6. PMID:8499455
- ↑ Huang CS, Pedersen BP, Stokes DL. Crystal structure of the potassium-importing KdpFABC membrane complex. Nature. 2017 Jun 29;546(7660):681-685. doi: 10.1038/nature22970. Epub 2017 Jun, 21. PMID:28636601 doi:http://dx.doi.org/10.1038/nature22970
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