1k4c: Difference between revisions
New page: left|200px<br /> <applet load="1k4c" size="450" color="white" frame="true" align="right" spinBox="true" caption="1k4c, resolution 2.00Å" /> '''Potassium Channel K... |
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== | ==Potassium Channel KcsA-Fab complex in high concentration of K+== | ||
Ion transport proteins must remove an ion's hydration shell to coordinate | <StructureSection load='1k4c' size='340' side='right'caption='[[1k4c]], [[Resolution|resolution]] 2.00Å' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1k4c]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus] and [https://en.wikipedia.org/wiki/Streptomyces_lividans Streptomyces lividans]. The February 2003 RCSB PDB [https://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Potassium Channels'' by Shuchismita Dutta and David S. Goodsell is [https://dx.doi.org/10.2210/rcsb_pdb/mom_2003_2 10.2210/rcsb_pdb/mom_2003_2]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1K4C OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1K4C 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]] 2Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=DGA:DIACYL+GLYCEROL'>DGA</scene>, <scene name='pdbligand=F09:NONAN-1-OL'>F09</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=1k4c FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1k4c OCA], [https://pdbe.org/1k4c PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1k4c RCSB], [https://www.ebi.ac.uk/pdbsum/1k4c PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1k4c ProSAT]</span></td></tr> | |||
</table> | |||
== 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> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/k4/1k4c_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1k4c ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Ion transport proteins must remove an ion's hydration shell to coordinate the ion selectively on the basis of its size and charge. To discover how the K+ channel solves this fundamental aspect of ion conduction, we solved the structure of the KcsA K+ channel in complex with a monoclonal Fab antibody fragment at 2.0 A resolution. Here we show how the K+ channel displaces water molecules around an ion at its extracellular entryway, and how it holds a K+ ion in a square antiprism of water molecules in a cavity near its intracellular entryway. Carbonyl oxygen atoms within the selectivity filter form a very similar square antiprism around each K+ binding site, as if to mimic the waters of hydration. The selectivity filter changes its ion coordination structure in low K+ solutions. This structural change is crucial to the operation of the selectivity filter in the cellular context, where the K+ ion concentration near the selectivity filter varies in response to channel gating. | |||
Chemistry of ion coordination and hydration revealed by a K+ channel-Fab complex at 2.0 A resolution.,Zhou Y, Morais-Cabral JH, Kaufman A, MacKinnon R Nature. 2001 Nov 1;414(6859):43-8. PMID:11689936<ref>PMID:11689936</ref> | |||
== | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
</div> | |||
<div class="pdbe-citations 1k4c" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Antibody 3D structures|Antibody 3D structures]] | |||
*[[Potassium Channel|Potassium Channel]] | |||
*[[Potassium channel 3D structures|Potassium channel 3D structures]] | |||
*[[3D structures of non-human antibody|3D structures of non-human antibody]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Large Structures]] | |||
[[Category: Mus musculus]] | [[Category: Mus musculus]] | ||
[[Category: Potassium Channels]] | [[Category: Potassium Channels]] | ||
[[Category: | [[Category: RCSB PDB Molecule of the Month]] | ||
[[Category: Streptomyces lividans]] | [[Category: Streptomyces lividans]] | ||
[[Category: Kaufman | [[Category: Kaufman A]] | ||
[[Category: MacKinnon | [[Category: MacKinnon R]] | ||
[[Category: Morais-Cabral | [[Category: Morais-Cabral JH]] | ||
[[Category: Zhou | [[Category: Zhou Y]] | ||
