Nejvíce citovaný článek - PubMed ID 7804158
Both glucose-type monosaccharides and one of their metabolites are required for activation of yeast plasma membrane H(+)-ATPase
Addition of glucose to a resting cell suspension of the yeast Saccharomyces cerevisiae was accompanied by marked shifts of the G alpha-protein subunits from the plasma membrane to the cell interior. This process was rapid with half-times between < 10 and 20 s. The decrease of the plasma membrane pool of the Gi alpha/Go alpha- and Gq alpha/Gl 1 alpha-protein subunits correlated with an increase in acid-sensitive forms of these proteins which was recovered in the mitochondrial and/or lysosomal membrane fraction. In contrast to cells from higher organisms glucose-stimulated yeast exhibits an extremely rapid type of the redistribution (internalization). The question remains open as to the functional significance of the internalized forms of the G-proteins as these remain sequestered from the plasma membrane well after glucose has been consumed.
- MeSH
- glukosa farmakologie MeSH
- imunoblotting MeSH
- proteiny vázající GTP analýza biosyntéza MeSH
- Saccharomyces cerevisiae účinky léků metabolismus MeSH
- subcelulární frakce metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- glukosa MeSH
- proteiny vázající GTP MeSH
In the facultatively anaerobic yeast Saccharomyces cerevisiae the uptake rate and the accumulation ratio of 2-aminoisobutyric acid was decreased by some 30% by Fenton's reagent (FR), a powerful source of OH. radicals. Likewise, the uptake of glutamic acid, leucine and arginine was diminished. The mediated diffusion of 6-deoxy-D-glucose was not affected. The H+ symport of maltose and trehalose was inhibited by some 40% both in the initial rate and in the accumulation ratio. FR had a dramatic inhibitory effect when present during preincubation with 50 mmol/L glucose. In the obligately aerobic Lodderomyces elongisporus the uptake of all amino acids tested was decreased by 15-30%, that of 6-deoxy-D-glucose by about 10%. The initial rates of uptake of maltose and trehalose were depressed by FR by 40% and the acceleration of uptake observed after 8 min of incubation, was abolished by FR completely. Acidification rate of the external medium by S. cerevisiae in the presence of glucose or galactose was enhanced three-fold, that after subsequently added K+ was substantially decreased. FR appears to have a dual effect on sugar and amino acid transport processes in yeast: (1) it blocks carrier protein synthesis; (2) it inhibits the source of energy for transport. It does not appreciably affect the carrier proteins themselves.
- MeSH
- aktivní transport účinky léků MeSH
- aminokyseliny metabolismus MeSH
- fungální proteiny metabolismus MeSH
- kinetika MeSH
- koncentrace vodíkových iontů MeSH
- metabolismus sacharidů MeSH
- peroxid vodíku farmakologie MeSH
- Saccharomyces cerevisiae účinky léků metabolismus MeSH
- Saccharomycetales účinky léků metabolismus MeSH
- transportní proteiny metabolismus MeSH
- železo farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- aminokyseliny MeSH
- Fenton's reagent MeSH Prohlížeč
- fungální proteiny MeSH
- peroxid vodíku MeSH
- transportní proteiny MeSH
- železo MeSH
Classical isolation procedure for plasma membrane H(+)-ATPase of Saccharomyces cerevisiae based on fractional centrifugation yielded always a roughly two-fold greater amount of membranes when starting from glucitol-preincubated than from glucose-preincubated yeast. This difference persisted all the way to the purified plasma membranes and to the purified H(+)-ATPase. The ATP-hydrolyzing activity by plasma membranes was roughly twice greater in glucose-preincubated cells than in the D-glucitol-preincubated ones while the purified enzyme was 7 times more active after glucose than after glucitol. Effects of diethylstilbestrol, suloctidil, erythrosin B, vanadate and dicarbanonaboranuide were very similar on plasma membrane-localized and purified ATPases of both forms, suggesting that both preparations contain the two ATPase forms, the glucose-preincubated one being richer in the activated form while the glucitol-preincubated one contains less of it.
- MeSH
- adenosintrifosfát metabolismus MeSH
- buněčná membrána enzymologie MeSH
- inhibitory enzymů farmakologie MeSH
- kultivační média MeSH
- protonové ATPasy antagonisté a inhibitory izolace a purifikace metabolismus MeSH
- Saccharomyces cerevisiae enzymologie růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- adenosintrifosfát MeSH
- inhibitory enzymů MeSH
- kultivační média MeSH
- protonové ATPasy MeSH
