The transport rates of amino acids, ranging from L-Glu to L-Lys, uracil, adenine and sulfate and phosphate anions by Saccharomyces cerevisiae are greatly increased by preincubation with D-glucose in a nongrowth medium when a de novo synthesis of proteins takes place. In addition, some substrates, especially the inorganic anions, require the presence of glucose during their transport. This requirement has to do both with ongoing protein synthesis and degradation, as well as with providing energy and/or activating the plasma membrane H(+)-ATPase which supplies the protons to the H+ symports studied here.

• MeSH
• Adenine metabolism   MeSH
• Biological Transport, Active drug effects   MeSH
• Cycloheximide pharmacology   MeSH
• Phosphates metabolism   MeSH
• Fungal Proteins biosynthesis   metabolism   MeSH
• Glucose metabolism   pharmacology   MeSH
• Kinetics MeSH
• Glutamic Acid metabolism   MeSH
• Lysine metabolism   MeSH
• Proton-Translocating ATPases metabolism   MeSH
• Saccharomyces cerevisiae drug effects   metabolism   MeSH
• Sulfates metabolism   MeSH
• Carrier Proteins biosynthesis   metabolism   MeSH
• Uracil metabolism   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Adenine MeSH
• Cycloheximide MeSH
• Phosphates MeSH
• Fungal Proteins MeSH
• Glucose MeSH
• Glutamic Acid MeSH
• Lysine MeSH
• Proton-Translocating ATPases MeSH
• Sulfates MeSH
• Carrier Proteins MeSH
• Uracil MeSH

Effects of starvation and glucose preincubation on membrane potential, ATPase-mediated acidification and glutamic acid transport were studied in yeast species Saccharomyces cerevisiae, Schizosaccharomyces pombe, Dipodascus magnusii, Lodderomyces elongisporus and Rhodotorula gracilis. The membrane potential was highest after preincubation with glucose in all species but L. elongisporus and R. gracilis. In all cases the membranes were depolarized in the presence of 20 mmol/L KCl and hyperpolarized with 50 mumol/L diethylstilbestrol (DES). The extracellular acidification caused by addition of glucose was highest after preincubation with glucose in all cases except in R. gracilis where there was none. In all cases except in R. gracilis addition of KCl caused a marked increase in the acidification rate. Addition of DES with glucose caused a large decrease in rate in S. cerevisiae but had much less effect on the other species. Transport of glutamic acid was clearly increased after pretreatment with glucose in S. cerevisiae, S. pombe and D. magnusii (mainly due to enhanced synthesis of the carrier) but actually decreased in R. gracilis and L. elongisporus. Addition of DES had an inhibitory effect in all species but much more pronounced in S. cerevisiae and S. pombe than in others. In general, both the acidification and the transport of glutamate were enhanced after preincubation with glucose but much more so in the semianaerobic species, such as S. cerevisiae, than in the strict aerobes (R. gracilis) where the effect was occasionally negative. There was no relationship between the ATPase-mediated acidification and the membrane potential.

• MeSH
• Biological Transport, Active MeSH
• Diethylstilbestrol pharmacology   MeSH
• Species Specificity MeSH
• Glucose pharmacology   MeSH
• Glutamates pharmacokinetics   MeSH
• Kinetics MeSH
• Hydrogen-Ion Concentration MeSH
• Yeasts drug effects   metabolism   MeSH
• Glutamic Acid MeSH
• Membrane Potentials drug effects   MeSH
• Proton-Translocating ATPases metabolism   MeSH
• Rhodotorula drug effects   metabolism   MeSH
• Saccharomyces cerevisiae drug effects   metabolism   MeSH
• Saccharomycetales drug effects   metabolism   MeSH
• Schizosaccharomyces drug effects   metabolism   MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH
• Names of Substances
• Diethylstilbestrol MeSH
• Glucose MeSH
• Glutamates MeSH
• Glutamic Acid MeSH
• Proton-Translocating ATPases MeSH

The transport of inorganic phosphate anions into yeast cells (after preincubation with glucose, fructose or another metabolizable sugar, and in the presence of glucose) shows two kinetic components with half-saturation constants of 40 mumol/L and 2.4 mmol/L. The uptake was strikingly stimulated by 2-deoxy-D-glucose (2-dGlc) at lower concentrations but inhibited above 100 mmol/L. A similar stimulation was caused by adenine (0.01-1 mmol/L) and a very small one by uracil and inorganic sulfate. It is suggested that either a phosphorylation reaction accompanies the transport (2-dGlc) or that some compounds stimulate the H(+)-ATPase more than inorganic phosphate itself and thus increase its rate of transport.

• MeSH
• Adenine pharmacology   MeSH
• Adenosine Triphosphate metabolism   MeSH
• Deoxyglucose pharmacology   MeSH
• Phosphates metabolism   MeSH
• Phosphorylation MeSH
• Ion Transport drug effects   MeSH
• Kinetics MeSH
• Proton-Translocating ATPases metabolism   MeSH
• Saccharomyces cerevisiae drug effects   metabolism   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Adenine MeSH
• Adenosine Triphosphate MeSH
• Deoxyglucose MeSH
• Phosphates MeSH
• Proton-Translocating ATPases MeSH