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Updated: Jul 14, 2026

Measuring the Osmotic Water Permeability Coefficient (Pf) of Spherical Cells: Isolated Plant Protoplasts as an Example
Published on: October 8, 2014
Aquaporins with selectivity for unconventional permeants
1Department of Pharmaceutical Chemistry, University of Kiel, Gutenbergstrasse 76, 24118, Kiel, Germany.
Abstract:
The aquaporin protein family generally seems to be designed for the selective passage of water or glycerol. Charged molecules, metal ions and even protons are strictly excluded. Recently, particular aquaporin isoforms were reported to conduct unconventional permeants, i.e., the unpolar gases carbon dioxide and nitric oxide, the polar gas ammonia, the oxidative oxygen species hydrogen peroxide, and the metalloids antimonite, arsenite and silicic acid. Here, we summarize the available data on permeability properties and physiological settings of these aquaporins and we analyze which structural features might be connected to permeability for non-water, non-glycerol solutes.
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