6w0f: Difference between revisions
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<StructureSection load='6w0f' size='340' side='right'caption='[[6w0f]], [[Resolution|resolution]] 2.40Å' scene=''> | <StructureSection load='6w0f' size='340' side='right'caption='[[6w0f]], [[Resolution|resolution]] 2.40Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[6w0f]] is a 3 chain structure with sequence from [ | <table><tr><td colspan='2'>[[6w0f]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] and [https://en.wikipedia.org/wiki/Streptomyces_lividans Streptomyces lividans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6W0F OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6W0F FirstGlance]. <br> | ||
</td></tr><tr id=' | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.4Å</td></tr> | ||
<tr id=' | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><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'>[ | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=6w0f FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6w0f OCA], [https://pdbe.org/6w0f PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6w0f RCSB], [https://www.ebi.ac.uk/pdbsum/6w0f PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6w0f ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[ | [https://www.uniprot.org/uniprot/KCSA_STRLI KCSA_STRLI] Acts as a pH-gated potassium ion channel; changing the cytosolic pH from 7 to 4 opens the channel, although it is not clear if this is the physiological stimulus for channel opening. Monovalent cation preference is K(+) > Rb(+) > NH4(+) >> Na(+) > Li(+).<ref>PMID:7489706</ref> | ||
<div style="background-color:#fffaf0;"> | <div style="background-color:#fffaf0;"> | ||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
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</div> | </div> | ||
<div class="pdbe-citations 6w0f" style="background-color:#fffaf0;"></div> | <div class="pdbe-citations 6w0f" style="background-color:#fffaf0;"></div> | ||
==See Also== | |||
*[[Potassium channel 3D structures|Potassium channel 3D structures]] | |||
== References == | == References == | ||
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
[[Category: Large Structures]] | [[Category: Large Structures]] | ||
[[Category: | [[Category: Rattus norvegicus]] | ||
[[Category: | [[Category: Streptomyces lividans]] | ||
[[Category: | [[Category: Gong L]] | ||
[[Category: | [[Category: Li J]] | ||
[[Category: | [[Category: Rohaim A]] | ||
Revision as of 11:24, 11 October 2023
Closed-gate KcsA soaked in 0mM KCl/5mM BaCl2Closed-gate KcsA soaked in 0mM KCl/5mM BaCl2
Structural highlights
FunctionKCSA_STRLI Acts as a pH-gated potassium ion channel; changing the cytosolic pH from 7 to 4 opens the channel, although it is not clear if this is the physiological stimulus for channel opening. Monovalent cation preference is K(+) > Rb(+) > NH4(+) >> Na(+) > Li(+).[1] Publication Abstract from PubMedBarium (Ba(2+)) is a classic permeant blocker of potassium (K(+)) channels. The "external lock-in effect" in barium block experiments, whereby the binding of external K(+) impedes the forward translocation of the blocker, provides a powerful avenue to investigate the selectivity of the binding sites along the pore of potassium channels. Barium block experiments show that the external lock-in site is highly selective for K(+) over Na(+). Wild-type KcsA was crystallized in low K(+) conditions, and the crystals were soaked in solutions containing various concentrations of barium. Structural analysis reveals open and closed gate conformations of the KcsA channel. Anomalous diffraction experiments show that Ba(2+) primarily binds to the innermost site S4 of the selectivity filter of the open-gate conformation and also the site S2, but no binding is detected with the closed-gate conformation. Alchemical free-energy perturbation calculations indicate that the presence of a Ba(2+) ion in the selectivity filter boosts the specificity of K(+) binding relative to Na(+) in the external sites S0-S2. Open and Closed Structures of a Barium-Blocked Potassium Channel.,Rohaim A, Gong L, Li J, Rui H, Blachowicz L, Roux B J Mol Biol. 2020 Aug 7;432(17):4783-4798. doi: 10.1016/j.jmb.2020.06.012. Epub, 2020 Jun 29. PMID:32615129[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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