caa a22 4500 397521944 CHVBK 20180308164635.0 cr unu---uuuuu 161202e199509 xx s 000 0 eng 10.1093/jxb/46.9.1169 doi (NATIONALLICENCE)oxford-10.1093/jxb/46.9.1169 Differential stimulation by Cl− of H+ transport and ATPase activity in purified plasma membrane vesicles from maize (Zea mays L.) roots [Elektronische Daten] [Christopher D. Faraday, Roger M. Spanswick] Maize (Zea mays L.) root plasma membranes purified by the aqueous polymer two-phase technique have previously been shown to be very low in tonoplast H+ -ATPase and H+ -PPase activities. Western blots of a similar preparation showed that, compared to a microsomal fraction, there was practically no reaction with antibodies to the tonoplast enzymes, but a strong reaction with an antibody to the plasma membrane H+ -ATPase. Freeze/thaw treatment of the plasma membrane vesicles increased the proportion with an insideout orientation to about 40%. This preparation was used to demonstrate that substitution of KCl for K2S04 resulted in a 14-fold stimulation of H+ transport, but an increase in ATPase activity of less than 10%. In contrast to its effect on tonoplast vesicles, Cl− had only a small effect on the membrane potential of plasma membrane vesicles, assayed by oxonol V fluorescence quench recovery. To account for the apparent variability in the H+/ATP coupling ratio, it may be necessary to devise a model that takes into consideration the possibility of non-linear behaviour with respect to the membrane potential of the proton leak and/or of slip in the ATPase. © Oxford University Press RESEARCH PAPERS nationallicence ATPase nationallicence plasma membrane nationallicence anion stimulation nationallicence proton transport nationallicence Faraday Christopher D. Section of Plant Biology, Division of Biological Sciences, Plant Science Building, Cornell University, Ithaca, NY 14853-5908, USA aut Spanswick Roger M. Section of Plant Biology, Division of Biological Sciences, Plant Science Building, Cornell University, Ithaca, NY 14853-5908, USA aut Journal of Experimental Botany Oxford University Press 46/9(1995-09), 1169-1176 0022-0957 46:9<1169 1995 46 exbotj https://doi.org/10.1093/jxb/46.9.1169 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jxb/46.9.1169 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Faraday Christopher D. Section of Plant Biology, Division of Biological Sciences, Plant Science Building, Cornell University, Ithaca, NY 14853-5908, USA aut NATIONALLICENCE 700 1- Spanswick Roger M. Section of Plant Biology, Division of Biological Sciences, Plant Science Building, Cornell University, Ithaca, NY 14853-5908, USA aut NATIONALLICENCE 773 0- Journal of Experimental Botany Oxford University Press 46/9(1995-09), 1169-1176 0022-0957 46:9<1169 1995 46 exbotj Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford