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Updated: Jul 10, 2026

Measuring the Osmotic Water Permeability Coefficient (Pf) of Spherical Cells: Isolated Plant Protoplasts as an Example
Published on: October 8, 2014
Function of a separate NH3-pore in Aquaporin TIP2;2 from wheat
1Institute of Botany, Applied Plant Science, Darmstadt University of Technology, Schnittspahnstrasse 10, D-64287 Darmstadt, Germany.
Abstract:
Functional analysis of heterologously expressed TaTIP2;2 by means of stopped-flow spectrometric studies provide evidence for water and ammonia conductivity. A series of experiments under increasing pH indicate that the gaseous NH(3), rather than the ammonium ion NH(4)(+) was transported. Results from inhibitor studies strongly suggest that NH(3) is not transported in file with water, but through a separate pathway, which could be supplied by the 5th central pore in a tetramer conformation.
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