7lc3: Difference between revisions
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==== | ==CryoEM Structure of KdpFABC in E1-ATP state== | ||
<StructureSection load='7lc3' size='340' side='right'caption='[[7lc3]]' scene=''> | <StructureSection load='7lc3' size='340' side='right'caption='[[7lc3]], [[Resolution|resolution]] 3.23Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id= OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol= FirstGlance]. <br> | <table><tr><td colspan='2'>[[7lc3]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7LC3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7LC3 FirstGlance]. <br> | ||
</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=7lc3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7lc3 OCA], [https://pdbe.org/7lc3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7lc3 RCSB], [https://www.ebi.ac.uk/pdbsum/7lc3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7lc3 ProSAT]</span></td></tr> | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.23Å</td></tr> | ||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=9Y0:(2R)-3-(((2-aminoethoxy)(hydroxy)phosphoryl)oxy)-2-(palmitoyloxy)propyl+(E)-octadec-9-enoate'>9Y0</scene>, <scene name='pdbligand=ACP:PHOSPHOMETHYLPHOSPHONIC+ACID+ADENYLATE+ESTER'>ACP</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=7lc3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7lc3 OCA], [https://pdbe.org/7lc3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7lc3 RCSB], [https://www.ebi.ac.uk/pdbsum/7lc3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7lc3 ProSAT]</span></td></tr> | |||
</table> | </table> | ||
== Function == | |||
[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;"> | |||
== Publication Abstract from PubMed == | |||
KdpFABC is an oligomeric K(+) transport complex in prokaryotes that maintains ionic homeostasis under stress conditions. The complex comprises a channel-like subunit (KdpA) from the superfamily of K(+) transporters and a pump-like subunit (KdpB) from the superfamily of P-type ATPases. Recent structural work has defined the architecture and generated contradictory hypotheses for the transport mechanism. Here, we use substrate analogs to stabilize four key intermediates in the reaction cycle and determine the corresponding structures by cryogenic electron microscopy. We find that KdpB undergoes conformational changes consistent with other representatives from the P-type superfamily, whereas KdpA, KdpC, and KdpF remain static. We observe a series of spherical densities that we assign as K(+) or water and which define a pathway for K(+) transport. This pathway runs through an intramembrane tunnel in KdpA and delivers ions to sites in the membrane domain of KdpB. Our structures suggest a mechanism where ATP hydrolysis is coupled to K(+) transfer between alternative sites in KdpB, ultimately reaching a low-affinity site where a water-filled pathway allows release of K(+) to the cytoplasm. | |||
Structural basis for potassium transport in prokaryotes by KdpFABC.,Sweet ME, Larsen C, Zhang X, Schlame M, Pedersen BP, Stokes DL Proc Natl Acad Sci U S A. 2021 Jul 20;118(29):e2105195118. doi: , 10.1073/pnas.2105195118. PMID:34272288<ref>PMID:34272288</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 7lc3" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[ATPase 3D structures|ATPase 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
[[Category: Escherichia coli K-12]] | |||
[[Category: Large Structures]] | [[Category: Large Structures]] | ||
[[Category: | [[Category: Larsen C]] | ||
[[Category: Pedersen BP]] | |||
[[Category: Stokes DL]] | |||
[[Category: Sweet ME]] | |||
Latest revision as of 22:37, 29 May 2024
CryoEM Structure of KdpFABC in E1-ATP stateCryoEM Structure of KdpFABC in E1-ATP state
Structural highlights
FunctionKDPA_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 PubMedKdpFABC is an oligomeric K(+) transport complex in prokaryotes that maintains ionic homeostasis under stress conditions. The complex comprises a channel-like subunit (KdpA) from the superfamily of K(+) transporters and a pump-like subunit (KdpB) from the superfamily of P-type ATPases. Recent structural work has defined the architecture and generated contradictory hypotheses for the transport mechanism. Here, we use substrate analogs to stabilize four key intermediates in the reaction cycle and determine the corresponding structures by cryogenic electron microscopy. We find that KdpB undergoes conformational changes consistent with other representatives from the P-type superfamily, whereas KdpA, KdpC, and KdpF remain static. We observe a series of spherical densities that we assign as K(+) or water and which define a pathway for K(+) transport. This pathway runs through an intramembrane tunnel in KdpA and delivers ions to sites in the membrane domain of KdpB. Our structures suggest a mechanism where ATP hydrolysis is coupled to K(+) transfer between alternative sites in KdpB, ultimately reaching a low-affinity site where a water-filled pathway allows release of K(+) to the cytoplasm. Structural basis for potassium transport in prokaryotes by KdpFABC.,Sweet ME, Larsen C, Zhang X, Schlame M, Pedersen BP, Stokes DL Proc Natl Acad Sci U S A. 2021 Jul 20;118(29):e2105195118. doi: , 10.1073/pnas.2105195118. PMID:34272288[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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