[Active electrogenic transport H+ in plasma membrane vesicles of cow parsnip phloem cells].
Generation of electric (delta psi) and chemical (delta pH) components of electrochemical proton gradient delta muH+, in plasma membrane vesicles of Heracleum sosnovskyi phloem cells was investigated. ATP-dependent generation of delta psi at pH 6.0 in the presence of Mg2+ and K+ was established with the help of fluorescent probes AU+ and ANS-. Protonophore CCCP and proton ATPase inhibitor DCCD suppressed generation, whereas oligomycin, the inhibitor of mitochondrial ATPases did not affect it. Measurings of delta psi value indicated its oscillations within the limits from 10 to 60 mV. ATP-dependent generation of delta pH was established by means of fluorescent probe 9-AA. The effect was eliminated by CCCP and stimulated by K+, that may testify to the transformation of a part of delta psi into delta pH at antiport H+/K+. Existence of H+-ATPase in the plasma membranes of higher plant cells insuring generation of delta muH+ is supposed.
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D001693:Biological Transport, Active / Q000187:drug effects; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D004579:Electron Transport; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010944:Plants / Q000378:metabolism*; D006180:Proton-Translocating ATPases
D004024:Dicyclohexylcarbodiimide; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; D000251:Adenosine Triphosphatases; D006180:Proton-Translocating ATPases
Aktivnyĭ élektrogennyĭ transport H+ v vezikulakh plazmaticheckikh membran kletok floémy borshchevika.