|
|
| (2 intermediate revisions not shown.) |
| Line 1: |
Line 1: |
| | | | |
| | ==KCSA POTASSIUM CHANNEL WITH TBA (TETRABUTYLAMMONIUM) AND RUBIDIUM== | | ==KCSA POTASSIUM CHANNEL WITH TBA (TETRABUTYLAMMONIUM) AND RUBIDIUM== |
| - | <StructureSection load='1jvm' size='340' side='right' caption='[[1jvm]], [[Resolution|resolution]] 2.80Å' scene=''> | + | <StructureSection load='1jvm' size='340' side='right'caption='[[1jvm]], [[Resolution|resolution]] 2.80Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[1jvm]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/"actinomyces_lividans"_krasil'nikov_et_al._1965 "actinomyces lividans" krasil'nikov et al. 1965]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JVM OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1JVM FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[1jvm]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_lividans Streptomyces lividans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JVM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1JVM FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=RB:RUBIDIUM+ION'>RB</scene>, <scene name='pdbligand=TBA:TETRABUTYLAMMONIUM+ION'>TBA</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]] 2.8Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1j95|1j95]], [[1bl8|1bl8]]</td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=RB:RUBIDIUM+ION'>RB</scene>, <scene name='pdbligand=TBA:TETRABUTYLAMMONIUM+ION'>TBA</scene></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=1jvm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jvm OCA], [http://pdbe.org/1jvm PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1jvm RCSB], [http://www.ebi.ac.uk/pdbsum/1jvm PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1jvm ProSAT]</span></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=1jvm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jvm OCA], [https://pdbe.org/1jvm PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1jvm RCSB], [https://www.ebi.ac.uk/pdbsum/1jvm PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1jvm ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://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> | + | [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 == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
| Line 29: |
Line 29: |
| | </div> | | </div> |
| | <div class="pdbe-citations 1jvm" style="background-color:#fffaf0;"></div> | | <div class="pdbe-citations 1jvm" style="background-color:#fffaf0;"></div> |
| | + | |
| | + | ==See Also== |
| | + | *[[Potassium channel 3D structures|Potassium channel 3D structures]] |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Actinomyces lividans krasil'nikov et al. 1965]] | + | [[Category: Large Structures]] |
| - | [[Category: MacKinnon, R]] | + | [[Category: Streptomyces lividans]] |
| - | [[Category: Morais-Cabral, J H]] | + | [[Category: MacKinnon R]] |
| - | [[Category: Zhou, Y]] | + | [[Category: Morais-Cabral JH]] |
| - | [[Category: Membrane protein]]
| + | [[Category: Zhou Y]] |
| - | [[Category: Metal transport]]
| + | |
| - | [[Category: Potassium channel]]
| + | |
| Structural highlights
Function
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(+).[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The K+ selectivity filter catalyses the dehydration, transfer and rehydration of a K+ ion in about ten nanoseconds. This physical process is central to the production of electrical signals in biology. Here we show how nearly diffusion-limited rates are achieved, by analysing ion conduction and the corresponding crystallographic ion distribution in the selectivity filter of the KcsA K+ channel. Measurements with K+ and its slightly larger analogue, Rb+, lead us to conclude that the selectivity filter usually contains two K+ ions separated by one water molecule. The two ions move in a concerted fashion between two configurations, K+-water-K+-water (1,3 configuration) and water-K+-water-K+ (2,4 configuration), until a third ion enters, displacing the ion on the opposite side of the queue. For K+, the energy difference between the 1,3 and 2,4 configurations is close to zero, the condition of maximum conduction rate. The energetic balance between these configurations is a clear example of evolutionary optimization of protein function.
Energetic optimization of ion conduction rate by the K+ selectivity filter.,Morais-Cabral JH, Zhou Y, MacKinnon R Nature. 2001 Nov 1;414(6859):37-42. PMID:11689935[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Schrempf H, Schmidt O, Kummerlen R, Hinnah S, Muller D, Betzler M, Steinkamp T, Wagner R. A prokaryotic potassium ion channel with two predicted transmembrane segments from Streptomyces lividans. EMBO J. 1995 Nov 1;14(21):5170-8. PMID:7489706
- ↑ Morais-Cabral JH, Zhou Y, MacKinnon R. Energetic optimization of ion conduction rate by the K+ selectivity filter. Nature. 2001 Nov 1;414(6859):37-42. PMID:11689935 doi:http://dx.doi.org/10.1038/35102000
|
