![]()
|
|
||||||||
J. Biol. Chem., Vol. 266, Issue 19, 12146-12151, 07, 1991
CC Van Leeuwen, E Postma, PJ Van den Broek and J Van Steveninck
Galactose transport was studied in membrane vesicles, prepared by fusion of
plasma membranes from the yeast Kluyveromyces marxianus with
proteoliposomes containing beef heart cytochrome c oxidase as a proton-
motive force-generating system. Sugar transport studies performed under
nonenergized conditions revealed that, even at high protein to phospholipid
ratios, not all vesicles contained a D-galactose-specific transporter. The
amount of vesicles containing an active carrier proved to be proportional
to the amount of plasma membrane protein present in the fusion mixture. By
addition of a suitable electron donor system a proton-motive force of -160
mV could be generated, inside alkaline and negative. Moreover, D-galactose
accumulation was observed. It was found that D-galactose accumulation was
highly dependent on the phospholipid composition of the vesicles, whereas
generation of a proton-motive force was not. Best results were obtained
with vesicles prepared with Escherichia coli phospholipid, giving a
galactose accumulation of 14 times. Uphill transport could be established
under conditions where only the pH gradient or the electrical gradient was
present. Moreover, kinetic analysis of the galactose transport activity in
energized vesicles revealed influx with a Km value of 540 microM, which is
in good agreement with the apparent affinity constant obtained with whole
cells. These results establish that galactose transport of K. marxianus is
a proton-motive force-driven process. Moreover it demonstrates that plasma
membrane vesicles co-reconstituted with cytochrome c oxidase are a valuable
resource for the analysis of proton-motive force-driven sugar transport
systems of yeast.
Proton-motive force-driven D-galactose transport in plasma membrane vesicles from the yeast Kluyveromyces marxianus
Department of Medical Biochemistry, Sylvius Laboratory, Leiden, The Netherlands.
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
H. Gerós, F. Baltazar, F. Cássio, and C. Leão L-[U-14C]Lactate binding to a 43 kDa protein in plasma membranes of Candida utilis Microbiology, March 1, 2000; 146(3): 695 - 699. [Abstract] [Full Text] |
||||
![]() |
B. Pinson, C. Napias, J. Chevallier, P. J. A. Van den Broek, and D. Brethes Characterization of the Saccharomyces cerevisiae Cytosine Transporter Using Energizable Plasma Membrane Vesicles J. Biol. Chem., November 14, 1997; 272(46): 28918 - 28924. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |