1ots
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Structure of the Escherichia coli ClC Chloride channel and Fab Complex
OverviewOverview
ClC channels conduct chloride (Cl-) ions across cell membranes and thereby govern the electrical activity of muscle cells and certain neurons, the transport of fluid and electrolytes across epithelia, and the acidification of intracellular vesicles. The structural basis of ClC channel gating was studied. Crystal structures of wild-type and mutant Escherichia coli ClC channels bound to a monoclonal Fab fragment reveal three Cl- binding sites within the 15-angstrom neck of an hourglass-shaped pore. The Cl- binding site nearest the extracellular solution can be occupied either by a Cl- ion or by a glutamate carboxyl group. Mutations of this glutamate residue in Torpedo ray ClC channels alter gating in electrophysiological assays. These findings reveal a form of gating in which the glutamate carboxyl group closes the pore by mimicking a Cl- ion.
About this StructureAbout this Structure
1OTS is a Single protein structure of sequence from Escherichia coli and Mus musculus with as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Gating the selectivity filter in ClC chloride channels., Dutzler R, Campbell EB, MacKinnon R, Science. 2003 Apr 4;300(5616):108-12. Epub 2003 Mar 20. PMID:12649487
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