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
• adenin metabolismus   MeSH
• aktivní transport účinky léků   MeSH
• cykloheximid farmakologie   MeSH
• fosfáty metabolismus   MeSH
• fungální proteiny biosyntéza   metabolismus   MeSH
• glukosa metabolismus   farmakologie   MeSH
• kinetika MeSH
• kyselina glutamová metabolismus   MeSH
• lysin metabolismus   MeSH
• protonové ATPasy metabolismus   MeSH
• Saccharomyces cerevisiae účinky léků   metabolismus   MeSH
• sírany metabolismus   MeSH
• transportní proteiny biosyntéza   metabolismus   MeSH
• uracil metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adenin MeSH
• cykloheximid MeSH
• fosfáty MeSH
• fungální proteiny MeSH
• glukosa MeSH
• kyselina glutamová MeSH
• lysin MeSH
• protonové ATPasy MeSH
• sírany MeSH
• transportní proteiny MeSH
• uracil MeSH

The degree of ATP depletion caused by glucose in a glucosephosphate isomerase-deficient strain of Saccharomyces cerevisiae was determined. Even in the presence of a sugar normally fermentable by the mutant, the addition of glucose can decrease the intracellular ATP, depending on the competition of the sugars for transport and subsequent phosphorylation. For both parent and mutant cells, a correlation exists between the calculated velocity of ATP formation or ATP consumption during the utilization of different concentrations of sugars and the experimental intracellular ATP level. For initially resting yeast cells, a rate increase of 35 mumol per min per g ATP was calculated to increase the intracellular level of this nucleotide by 1 mumol per g cell mass.

• MeSH
• adenosintrifosfát metabolismus   MeSH
• fosforylace MeSH
• glukosa-6-fosfátisomerasa metabolismus   MeSH
• glukosa metabolismus   MeSH
• metabolismus sacharidů MeSH
• mutace MeSH
• Saccharomyces cerevisiae enzymologie   genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adenosintrifosfát MeSH
• glukosa-6-fosfátisomerasa MeSH
• glukosa MeSH

Protoplasts of Saccharomyces cerevisiae prepared by snail-gut juice treatment were compared in their transport properties with intact cells. 1. Constitutive monosaccharide transport (D-xylose, 6-deoxy-D-glucose), as well as inducible transport of D-galactose, were unaltered. 2. Phosphorylation-associated transport of 2-deoxy-D-glucose was enhanced in protoplasts, possibly as a consequence of removal of the unstirred layer of the cell wall. 3. Proton-driven transports of trehalose, L-leucine, L-proline and monophosphate could not be activated by preincubation with D-glucose, apparently owing to lack of proton-solute coupling in transport. Utilization of glucose was not depressed but respiration was reduced by about 50% while acidification of the external medium after glucose addition was inhibited by more than 90%. This may be related to the inability of protoplast plasma membrane H-ATPase to be activated by glucose and hence to impaired proton-translocating capacity. Uranyl ions inhibited generally much less in protoplasts than in intact cells although their binding to protoplasts was greater (maximum 0.68 fmol per cell but 3.2 fmol per protoplast).

• MeSH
• biologický transport MeSH
• ethanol metabolismus   MeSH
• glukosa metabolismus   MeSH
• monosacharidy metabolismus   MeSH
• proteiny přenášející monosacharidy MeSH
• protonové ATPasy metabolismus   MeSH
• protoplasty metabolismus   MeSH
• Saccharomyces cerevisiae metabolismus   MeSH
• transportní proteiny metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ethanol MeSH
• glukosa MeSH
• monosacharidy MeSH
• proteiny přenášející monosacharidy MeSH
• protonové ATPasy MeSH
• transportní proteiny MeSH

Maltotriose is metabolized by baker's and brewer's yeast only oxidatively, with a respiratory quotient of 1.0, the QCO2Ar being, depending on the strain used, 0-11, as compared with QCO2air of 6-42 microL CO2 per h per mg dry substance. The transport appeared to proceed by facilitated diffusion (no effects of NaF, iodoacetamide and 3-chlorophenylhydrazonomalononitrile) with a KT of more than 50 mM and was inhibited by maltose greater than maltotriose greater than methyl-alpha-D-glucoside greater than maltotetraose greater than D-fructose greater than D-glucose. The transport was present constitutively in both Saccharomyces cerevisiae (baker's yeast) and in S. uvarum (brewer's yeast) and it was not significantly stimulated by preincubation with glucose or maltose. The pH optimum was 4.5-5.5, the temperature dependence yielded an activation energy of 26 kJ/mol.

• MeSH
• biologický transport MeSH
• oligosacharidy metabolismus   MeSH
• Saccharomyces cerevisiae metabolismus   MeSH
• Saccharomyces metabolismus   MeSH
• spotřeba kyslíku MeSH
• trisacharidy metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• maltotriose MeSH Prohlížeč
• oligosacharidy MeSH
• trisacharidy MeSH

The anomeric specificity of monosaccharide uptake was investigated in 42 species of yeasts and related mycelium-forming fungi. Differences in the uptake of anomers were determined by the following methods. (1) Shift of anomeric equilibrium in the outer medium caused by preferential uptake of one of the anomeric forms was monitored polarimetrically as induced mutarotation. (2) The uptake of 14C-D-glucose by cells was examined after addition of freshly prepared solutions of alpha- or beta-D-glucose. Most of the organisms examined display the Saccharomyces-type preference for the alpha-anomers of glucose and xylose which is caused by the higher affinity of the monosaccharide carrier for the alpha-pyranose configuration. The following genera show this type of preference (the number of species is given in parenthesis): Saccharomyces (5), Schizosaccharomyces (1), Endomycopsis (2), Eremascus (1), Endomyces (1), Pichia (1), Hansenula (1), Debaryomyces (2), Lipomyces (1), Willia (1), Nematospora (1), Kluyveromyces (2), Candida (5), Torulopsis (5), Cryptococcus (1). No anomeric specificity was shown by the following genera: Nadsonia (1), Dipodascus (2), Rhodotorula (5), Sporobolomyces (2), Bullera (1), Rhodosporidium (1). A parallel investigation of the concentration dependence of glucose uptake indicates that most yeasts possess a constitutive monosaccharide carrier characterized by the following features: a high maximum rate of uptake, a relatively low affinity, and preference for alpha-anomers. Besides this carrier the majority of these microorganisms possess a glucose-transporting carrier with a higher affinity and a lower capacity.

• MeSH
• aktivní transport MeSH
• druhová specificita MeSH
• glukosa metabolismus   MeSH
• houby metabolismus   MeSH
• kvasinky metabolismus   MeSH
• monosacharidy metabolismus   MeSH
• proteiny přenášející monosacharidy MeSH
• stereoizomerie MeSH
• transportní proteiny metabolismus   MeSH
• xylosa metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• glukosa MeSH
• monosacharidy MeSH
• proteiny přenášející monosacharidy MeSH
• transportní proteiny MeSH
• xylosa MeSH

After growth on sucrose or glucose, Endomyces magnusii possess a monosaccharide uptake which resembles that of Saccharomyces cerevisiae (a high KT of uptake, preference for alpha-anomers of D-xylose and D-glucose, enhanced uptake during anaerobiosis, attainment of a diffusion equilibrium). The uptake is inhibited by other monosaccharides and especially strongly by D-galactose. In the absence of high concentrations of metabolizable sugars. E. magnusii develops a capacity to accumulate 3-O-methyl-D-glucose and D-xylose against a concentration gradient the new system displaying a high affinity for glucose (KT less than 0.1 mM), repression by glucose, mannose or galactose. Cycloheximide (0.2%) blocks the formation of the active system.

• MeSH
• Ascomycota metabolismus   MeSH
• galaktosa farmakologie   MeSH
• glukosa metabolismus   MeSH
• mannosa farmakologie   MeSH
• monosacharidy metabolismus   MeSH
• ribosa farmakologie   MeSH
• Saccharomycetales metabolismus   MeSH
• sorbosa farmakologie   MeSH
• xylosa metabolismus   farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• galaktosa MeSH
• glukosa MeSH
• mannosa MeSH
• monosacharidy MeSH
• ribosa MeSH
• sorbosa MeSH
• xylosa MeSH

Using incubation in the presence of 0.4 mM cycloheximide the half-lives of the principal membrane transport proteins in baker's yeast were found to be: more than 24 h for the constitutive glucose carrier, 2.2 h for the inducible galactose carrier, 1.2 h for the inducible maltose carrier and 0.8 h for the inducible alpha-methyl-D-glucoside carrier. The distinct nature of the two last-named carriers was thus supported. De-induction of the galactose carrier was enhanced in the presence of glucose plus cycloheximide but not of either substance alone. Chloramphenicol suppressed all effects of cycloheximide. In contrast to the enzymes of galactose metabolism, the induction of the glactose carrier was not under the control of a mitochondrial factor and took place in a rho-mutant. The system induced by maltose but not the one induced by alpha-methyl-D-glucoside was de-induced rapidly by the intervention of a cytoplasm-synthesized protein.

• MeSH
• chloramfenikol farmakologie   MeSH
• cykloheximid farmakologie   MeSH
• galaktosa metabolismus   MeSH
• glukosa metabolismus   MeSH
• metabolismus sacharidů * MeSH
• methylglukosidy metabolismus   MeSH
• poločas MeSH
• Saccharomyces cerevisiae metabolismus   MeSH
• transportní proteiny metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chloramfenikol MeSH
• cykloheximid MeSH
• galaktosa MeSH
• glukosa MeSH
• methylglukosidy MeSH
• transportní proteiny MeSH

The ability of Saccharomyces cerevisiae to transport D-galactose and related sugars with an axial hydroxyl group at C-4, acquired by induction with D-galactose, was lost either by exposing early exponential-phase cells to an osmotic shock involving incubation in 0.6M NaC1O4, 0.66M sucrose and 1mM histidine and transfer to 5mM Tris-HC1 with 2mM dithiothreitol, or simply by transferring them to distilled water. The total amount of protein thus released was 0.1--0.35 and 0.1 mg per mg dry wt., respectively. The shock fluid contained at least six proteins, among them a galactose-binding component. L-Arabinose transport could not be restored by adding the concentrated shock fluid to depleted cells but cells remained viable after the shock and resynthesized the transport system if incubated in a galactose-containing growth medium.

• MeSH
• aktivní transport MeSH
• arabinosa metabolismus   MeSH
• fungální proteiny biosyntéza   MeSH
• galaktosa metabolismus   MeSH
• osmóza MeSH
• Saccharomyces cerevisiae metabolismus   MeSH
• stereoizomerie MeSH
• transportní proteiny metabolismus   MeSH
• xylosa metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• arabinosa MeSH
• fungální proteiny MeSH
• galaktosa MeSH
• transportní proteiny MeSH
• xylosa MeSH

Tritium-labelled 4-deoxy-D-glucose (4-dglc) and 6-deoxy-D-glucose (6-dgcl) were prepared by catalytic hydrogenolysis of the corresponding deoxyiodo derivatives with gaseous tritium. The two sugars are transported into Saccharomyces cerevisiae by both the constitutive glucose and the inducible galactose carrier. Uranyl ions are powerful inhibitors. The pH optimum in uninduced cells lies at 5.5 for both sugars, the apparent activation energies (between 15 and 35 degrees C) are 25.1 kJ/mol and 16.5 kJ/mol, respectively. The steady-state intracellular concentration of both sugars is less than the extracellular one (no uphill transport). Neither of them is a substrate of yeast hexokinase. 4-Deoxy-D-glucose undergoes a dinitrophenol-sensitive conversion to an unknown metabolite which is not phosphorylated and may represent one of its oxidation products.

• MeSH
• deoxycukry metabolismus   MeSH
• deoxyglukosa chemická syntéza   metabolismus   MeSH
• dinitrofenoly farmakologie   MeSH
• fruktosa metabolismus   MeSH
• glukosa metabolismus   MeSH
• hexokinasa metabolismus   MeSH
• jodacetamid farmakologie   MeSH
• koncentrace vodíkových iontů MeSH
• Saccharomyces cerevisiae enzymologie   metabolismus   MeSH
• teplota MeSH
• transport elektronů MeSH
• uran farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• deoxycukry MeSH
• deoxyglukosa MeSH
• dinitrofenoly MeSH
• fruktosa MeSH
• glukosa MeSH
• hexokinasa MeSH
• jodacetamid MeSH
• uran MeSH

Acyclic polyols (erythritol, xylitol, ribitol, D-arabinitol, mannitol, sorbitol and galactitol) are not metabolized by Saccharomyces cerevisiae. They are taken up by a fast non-active process, reaching 40-70% distribution referred to total cell water. The uptake is insensitive to temperature, pH (between 4 and 8), 2,4-dinitrophenol and uranyl ions. Its initial rate rises linearly with concentration from 10(-5)M to 1M. The process resembles simple diffusion through large pores or the trapping of the whole solution on the surface. Protoplasts behave like whole cells in this respect. Only erythritol shows a second type of uptake which is inhibitor-insensitive but temperature-dependent.

• MeSH
• aktivní transport MeSH
• buněčná membrána metabolismus   MeSH
• cukerné alkoholy metabolismus   MeSH
• dinitrofenoly farmakologie   MeSH
• kinetika MeSH
• koncentrace vodíkových iontů MeSH
• polysacharidy metabolismus   MeSH
• protoplasty metabolismus   MeSH
• Saccharomyces cerevisiae metabolismus   MeSH
• teplota MeSH
• uran farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cukerné alkoholy MeSH
• dinitrofenoly MeSH
• polysacharidy MeSH
• uran MeSH