Mechanism of hydrogen ion transport in the diluting segment of frog kidney

1984 ◽  
Vol 402 (3) ◽  
pp. 272-280 ◽  
Author(s):  
Hans Oberleithner ◽  
Florian Lang ◽  
Georg Messner ◽  
Wenhui Wang
Keyword(s):  
Ion Transport ◽  
Hydrogen Ion ◽  
Frog Kidney ◽  
Diluting Segment ◽  
Hydrogen Ion Transport

scholarly journals ACTION OF TRITON X-100 ON CHLOROPLAST MEMBRANES

1967 ◽  
Vol 33 (2) ◽  
pp. 395-410 ◽  
Author(s):  
David W. Deamer ◽  
Antony Crofts
Keyword(s):  
Ion Transport ◽  
Conformational Changes ◽  
Active Material ◽  
Active Species ◽  
Hydrogen Ion ◽  
Electron Microscopic ◽  
Chloroplast Membranes ◽  
Ionic Equilibrium ◽  
Hydrogen Ion Transport ◽  
Triton X

Addition of Triton X-100 to chloroplast suspensions to a final concentration of 100–200 µM causes an approximate tripling of chloroplast volume and complete inhibition of light-induced conformational changes, light-dependent hydrogen ion transport, and photophosphorylation. Electron microscopic studies show that chloroplasts treated in this manner manifest extensive swelling in the form of vesicles within their inner membrane structure. Triton was adsorbed to chloroplast membranes in a manner suggesting a partition between the membrane phase and the suspending medium, rather than a strong, irreversible binding. This adsorption results in the production of pores through which ions may freely pass, and it is suggested that the inhibition of conformational changes, hydrogen ion transport, and photophosphorylation by Triton is due to an inability of treated chloroplast membranes to maintain a light-dependent pH gradient. The observed swelling is due to water influx in response to a fixed, osmotically active species within the chloroplasts, after ionic equilibrium has occurred. This is supported by the fact that chloroplasts will shrink upon Triton addition if a nonpenetrating, osmotically active material such as dextran or polyvinylpyrrolidone is present externally in sufficient concentration (>0.1 mM) to offset the osmotic activity of the internal species.

Electro-osmosis and hydrogen-ion transport in cation-exchange membranes

1967 ◽  
Vol 20 (12) ◽  
pp. 2575 ◽  
Author(s):  
R Arnold ◽  
DA Swift
Keyword(s):  
Ion Transport ◽  
Cation Exchange ◽  
Acid Concentration ◽  
Water Flux ◽  
Transference Number ◽  
Hydrogen Ion ◽  
Transference Numbers ◽  
Transport Numbers ◽  
Electro Osmosis ◽  
Hydrogen Ion Transport

Hydrogen-ion transport numbers, water transference numbers, and acid absorption are reported for some cation-exchange membranes in presence of 0.1N, 1.0N, and 5.0N sulphuric acid. The transport numbers of hydrogen ion remain fairly close to unity even at the highest acid concentration; this is largely due to the retardation of the anions by the electro-osmotic water flux. With increasing acid concentration the water transference number falls to a lower limit of 1.0 mole per faraday; with the driest membrane used this value is obtained at all acid concentrations used. This behaviour suggests that when there are less than about 11 moles of water available per hydrogen ion in the membrane, association occurs between sulphonate groups and hydrogen ions, with consequent immobilization of the latter.

Hydrogen ion transport in Epithelia

FEBS Letters ◽  
1982 ◽  
Vol 140 (1) ◽  
pp. 145-146
Author(s):  
R.J. Naftalin
Keyword(s):  
Ion Transport ◽  
Hydrogen Ion ◽  
Hydrogen Ion Transport
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