1k4c
From Proteopedia
(New page: 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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| - | [[Image:1k4c.gif|left|200px]]<br /> | + | [[Image:1k4c.gif|left|200px]]<br /><applet load="1k4c" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1k4c" size=" | + | |
caption="1k4c, resolution 2.00Å" /> | caption="1k4c, resolution 2.00Å" /> | ||
'''Potassium Channel KcsA-Fab complex in high concentration of K+'''<br /> | '''Potassium Channel KcsA-Fab complex in high concentration of K+'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Ion transport proteins must remove an ion's hydration shell to coordinate | + | 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. |
==About this Structure== | ==About this Structure== | ||
| - | 1K4C is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] and [http://en.wikipedia.org/wiki/Streptomyces_lividans Streptomyces lividans] with K, DGA and F09 as [http://en.wikipedia.org/wiki/ligands ligands]. The following page contains interesting information on the relation of 1K4C with [[http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb38_1.html Potassium Channels]]. Full crystallographic information is available from [http:// | + | 1K4C is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] and [http://en.wikipedia.org/wiki/Streptomyces_lividans Streptomyces lividans] with <scene name='pdbligand=K:'>K</scene>, <scene name='pdbligand=DGA:'>DGA</scene> and <scene name='pdbligand=F09:'>F09</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. The following page contains interesting information on the relation of 1K4C with [[http://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/pdb38_1.html Potassium Channels]]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1K4C OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Kaufman, A.]] | [[Category: Kaufman, A.]] | ||
[[Category: MacKinnon, R.]] | [[Category: MacKinnon, R.]] | ||
| - | [[Category: Morais-Cabral, J | + | [[Category: Morais-Cabral, J H.]] |
[[Category: Zhou, Y.]] | [[Category: Zhou, Y.]] | ||
[[Category: DGA]] | [[Category: DGA]] | ||
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[[Category: protein-antibody fab complex]] | [[Category: protein-antibody fab complex]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:30:01 2008'' |
Revision as of 11:30, 21 February 2008
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Potassium Channel KcsA-Fab complex in high concentration of K+
Overview
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.
About this Structure
1K4C is a Single protein structure of sequence from Mus musculus and Streptomyces lividans with , and as ligands. The following page contains interesting information on the relation of 1K4C with [Potassium Channels]. Full crystallographic information is available from OCA.
Reference
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
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