title: Leucine transport in plasma membrane vesicles of Saccharomyces cerevisiae.
abstract: Yeast plasma membrane vesicles were obtained by the fusion of liposomes with purified yeast membranes by means of the freeze thaw-sonication technique. Beef heart mitochondria cytochrome-c oxidase was incorporated into the vesicles. Addition of substrate (ascorbate/TMPD/cytochrome c) generated a membrane potential negative inside, and an alkaline pH gradient inside the vesicle, that served as the driving force for leucine transport. Both delta pH and delta psi could drive leucine transport. When delta pH was increased in the presence of valinomycin and potassium, at the expense of delta psi, leucine uptake increased by 10%.
authors.affiliation: Department of Microbiology, Universidad Nacional Autónoma de México, Mexico City.
authors.forename: M
authors.initials: M
authors.lastname: Calahorra
authors.forename: M
authors.initials: M
authors.lastname: Opekarová
authors.forename: J
authors.initials: J
authors.lastname: Ramirez
authors.forename: A
authors.initials: A
authors.lastname: Peña
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology; D001692:Biological Transport; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism; D003574:Cytochrome c Group / Q000494:pharmacology; D004563:Electrochemistry; D003576:Electron Transport Complex IV / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007930:Leucine / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects; D008929:Mitochondria, Heart / Q000201:enzymology; D011188:Potassium / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013772:Tetramethylphenylenediamine / Q000494:pharmacology; D014634:Valinomycin / Q000494:pharmacology
chemical_list: D003574:Cytochrome c Group; D008081:Liposomes; D014634:Valinomycin; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; D003576:Electron Transport Complex IV; D007930:Leucine; D013772:Tetramethylphenylenediamine; D001205:Ascorbic Acid; D011188:Potassium