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1kpk
From Proteopedia
(New page: 200px<br /><applet load="1kpk" size="450" color="white" frame="true" align="right" spinBox="true" caption="1kpk, resolution 3.50Å" /> '''Crystal Structure of...) |
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| - | [[Image:1kpk.gif|left|200px]]<br /><applet load="1kpk" size=" | + | [[Image:1kpk.gif|left|200px]]<br /><applet load="1kpk" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1kpk, resolution 3.50Å" /> | caption="1kpk, resolution 3.50Å" /> | ||
'''Crystal Structure of the ClC Chloride Channel from E. coli'''<br /> | '''Crystal Structure of the ClC Chloride Channel from E. coli'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The ClC chloride channels catalyse the selective flow of Cl- ions across | + | The ClC chloride channels catalyse the selective flow of Cl- ions across cell membranes, thereby regulating electrical excitation in skeletal muscle and the flow of salt and water across epithelial barriers. Genetic defects in ClC Cl- channels underlie several familial muscle and kidney diseases. Here we present the X-ray structures of two prokaryotic ClC Cl- channels from Salmonella enterica serovar typhimurium and Escherichia coli at 3.0 and 3.5 A, respectively. Both structures reveal two identical pores, each pore being formed by a separate subunit contained within a homodimeric membrane protein. Individual subunits are composed of two roughly repeated halves that span the membrane with opposite orientations. This antiparallel architecture defines a selectivity filter in which a Cl- ion is stabilized by electrostatic interactions with alpha-helix dipoles and by chemical coordination with nitrogen atoms and hydroxyl groups. These findings provide a structural basis for further understanding the function of ClC Cl- channels, and establish the physical and chemical basis of their anion selectivity. |
==About this Structure== | ==About this Structure== | ||
| - | 1KPK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http:// | + | 1KPK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KPK OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Cadene, M.]] | [[Category: Cadene, M.]] | ||
| - | [[Category: Campbell, E | + | [[Category: Campbell, E B.]] |
| - | [[Category: Chait, B | + | [[Category: Chait, B T.]] |
[[Category: Dutzler, R.]] | [[Category: Dutzler, R.]] | ||
[[Category: MacKinnon, R.]] | [[Category: MacKinnon, R.]] | ||
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[[Category: homodimer]] | [[Category: homodimer]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:36:34 2008'' |
Revision as of 11:36, 21 February 2008
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Crystal Structure of the ClC Chloride Channel from E. coli
Overview
The ClC chloride channels catalyse the selective flow of Cl- ions across cell membranes, thereby regulating electrical excitation in skeletal muscle and the flow of salt and water across epithelial barriers. Genetic defects in ClC Cl- channels underlie several familial muscle and kidney diseases. Here we present the X-ray structures of two prokaryotic ClC Cl- channels from Salmonella enterica serovar typhimurium and Escherichia coli at 3.0 and 3.5 A, respectively. Both structures reveal two identical pores, each pore being formed by a separate subunit contained within a homodimeric membrane protein. Individual subunits are composed of two roughly repeated halves that span the membrane with opposite orientations. This antiparallel architecture defines a selectivity filter in which a Cl- ion is stabilized by electrostatic interactions with alpha-helix dipoles and by chemical coordination with nitrogen atoms and hydroxyl groups. These findings provide a structural basis for further understanding the function of ClC Cl- channels, and establish the physical and chemical basis of their anion selectivity.
About this Structure
1KPK is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
X-ray structure of a ClC chloride channel at 3.0 A reveals the molecular basis of anion selectivity., Dutzler R, Campbell EB, Cadene M, Chait BT, MacKinnon R, Nature. 2002 Jan 17;415(6869):287-94. PMID:11796999
Page seeded by OCA on Thu Feb 21 13:36:34 2008
