Ion permeation through a Cl--selective channel designed from a CLC Cl-/H+ exchanger
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چکیده
منابع مشابه
Ion permeation through a Cl--selective channel designed from a CLC Cl-/H+ exchanger.
The CLC family of Cl(-)-transporting proteins includes both Cl(-) channels and Cl(-)/H(+) exchange transporters. CLC-ec1, a structurally known bacterial homolog of the transporter subclass, exchanges two Cl(-) ions per proton with strict, obligatory stoichiometry. Point mutations at two residues, Glu(148) and Tyr(445), are known to impair H(+) movement while preserving Cl(-) transport. In the x...
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CLC-ec1, a bacterial homologue of the CLC family's transporter subclass, catalyzes transmembrane exchange of Cl(-) and H(+). Mutational analysis based on the known structure reveals several key residues required for coupling H(+) to the stoichiometric countermovement of Cl(-). E148 (Glu(ex)) transfers protons between extracellular water and the protein interior, and E203 (Glu(in)) is thought to...
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CLC-5 is a H(+)/Cl(-) exchanger that is expressed primarily in endosomes but can traffic to the plasma membrane in overexpression systems. Mutations altering the expression or function of CLC-5 lead to Dent's disease. Currents mediated by this transporter show extreme outward rectification and are inhibited by acidic extracellular pH. The mechanistic origins of both phenomena are currently not ...
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CLC-ec1 is a prokaryotic CLC-type Cl(-)/H+ exchange transporter. Little is known about the mechanism of H+ coupling to Cl-. A critical glutamate residue, E148, was previously shown to be required for Cl(-)/H+ exchange by mediating proton transfer between the protein and the extracellular solution. To test whether an analogous H+ acceptor exists near the intracellular side of the protein, we per...
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The CLC proteins form a broad family of anion-selective transport proteins that includes both channels and exchangers. Despite extensive structural, functional, and computational studies, the transport mechanism of the CLC exchangers remains poorly understood. Several transport models have been proposed but have failed to capture all the key features of these transporters. Multiple CLC crystal ...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2008
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.0804503105