title: Deuterons cannot replace protons in active transport processes in yeast.
abstract: Replacement of ordinary water with heavy water causes a sharp reduction of the rates of both primary hydrogen ion transport (at the plasma membrane ATPase) and secondary symports (H(+)-associated transports of sugars and amino acids) in several species of yeast. At the same time, the hydrolytic activity of the ATPase is affected only very little. Likewise, the membrane potential, the delta pH and, correspondingly, the accumulation ratios of the various symported solutes are altered much less. This serves as evidence that H+ or H3O+ ions are direct participants in the various active transports of nutrients in yeast.
authors.affiliation: Department of Membrane Transport, Czechoslovak Academy of Sciences, Prague.
authors.forename: A
authors.initials: A
authors.lastname: Kotyk
authors.forename: M
authors.initials: M
authors.lastname: Dvoráková
authors.forename: J
authors.initials: J
authors.lastname: Koryta
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D001693:Biological Transport, Active; D003903:Deuterium / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008564:Membrane Potentials; D003904:Mitosporic Fungi / Q000378:metabolism*; D011522:Protons; D012248:Rhodotorula / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D004718:Saccharomycetales / Q000378:metabolism*
chemical_list: D011522:Protons; D003903:Deuterium; D000251:Adenosine Triphosphatases