A voltage-dependent porin-like channel in the inner envelope membrane of plant chloroplasts.
Abstract
The electrical activity of a single channel of 525 +/- 12 picosiemens in 150 mM KCl was measured after fusion of the inner envelope membrane of the chloroplast with planar lipid bilayers. The reversal potentials measured in KCl gradients indicate that this channel is weakly anion selective (PCl/PK = 1.6 +/- 0.2). The gating mechanism of the pore is voltage dependent. The channel shifts from a fully open state to a substrate at positive electrical potentials and remains closed at negative electrical potentials. Succinylation of the protein increases the open probability of the fully open state and reverses the channel selectivity. Analysis of the single-channel conductance as a function of the salt concentration and of the open probability at various voltages suggests that this channel is a new membrane porin not previously identified.
References
Citations
Related Concepts
Related Feeds
ASBMB Publications
The American Society for Biochemistry and Molecular Biology (ASBMB) includes the Journal of Biological Chemistry, Molecular & Cellular Proteomics, and the Journal of Lipid Research. Discover the latest research from ASBMB here.