Functional reconstitution of a prokaryotic K+ channel
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Updated: Oct 29, 2026

Reconstitution of a Kv Channel into Lipid Membranes for Structural and Functional Studies
Published on: July 13, 2013
L Heginbotham1, L Kolmakova-Partensky, C Miller
1Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, Massachusetts 02254, USA.
Abstract:
SliK, a K+ channel encoded by the Streptomyces KcsA gene, was expressed, purified, and reconstituted in liposomes. A concentrative 86Rb+ flux assay was used to assess the ion transport properties of SliK. SliK-mediated ionic flux shows strong selectivity for K+ over Na+ and is inhibited by micromolar concentrations of Ba2+, mirroring the basic permeation characteristic of eukaryotic K+ channels studied by electrophysiological methods. 86Rb+ uptake kinetics and equilibrium measurements also demonstrate that the purified protein is fully active.
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