Binding kinetics of quaternary ammonium ions in Kcv potassium channels.

ABSTRACT: Kcv channels from plant viruses represent the autonomous pore module of potassium channels, devoid of any regulatory domains. These small proteins show very reproducible single-channel behavior in planar lipid bilayers. Thus, they are an optimum system for the study of the biophysics of ion transport and gating. Structural models based on homology modeling have been used successfully, but experimental structural data are currently not available. Here we determine the size of the cytosolic pore entrance by studying the blocker kinetics. Blocker binding and dissociation rate constants ranging from 0.01 to 1000 ms^-1 were determined for different quaternary ammonium ions. We found that the cytosolic pore entrance of Kcv_NTS must be at least 11 Å wide. The results further i

SUBMITTER: Korn T 

PROVIDER: S-EPMC11575739 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature