1OTU

Structure of the Escherichia coli ClC Chloride channel E148Q mutant and Fab Complex

Summary for 1OTU

• Entry DOI: 10.2210/pdb1otu/pdb
• Related: 1OTS 1OTT
• Descriptor: Voltage-gated ClC-type chloride channel eriC, Fab fragment (Heavy chain), Fab fragment (Light chain), ... (4 entities in total)
• Functional Keywords: ion channel, clc chloride channel, fab complex, membrane protein
• Biological source: Escherichia coli; More
• Cellular location: Cell inner membrane; Multi-pass membrane protein (Probable): P37019
• Total number of polymer chains: 6
• Total formula weight: 193351.09

Authors

Dutzler, R.,Campbell, E.B.,MacKinnon, R. (deposition date: 2003-03-23, release date: 2003-04-15, Last modification date: 2023-08-16)

Primary citation

Dutzler, R.,Campbell, E.B.,MacKinnon, R.
Gating the Selectivity Filter in ClC Chloride Channels
Science, 300:108-112, 2003

PubMed Abstract: 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.

PubMed: 12649487
DOI: 10.1126/science.1082708

Experimental method

X-RAY DIFFRACTION (3.3 Å)