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Jure Piškur - One of the best experts on this subject based on the ideXlab platform.
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a study on the fundamental mechanism and the evolutionary driving forces behind aerobic fermentation in yeast
PLOS ONE, 2015Co-Authors: Arne Hagman, Jure PiškurAbstract:Baker’s yeast Saccharomyces cerevisiae rapidly converts sugars to ethanol and carbon dioxide at both anaerobic and aerobic conditions. The later phenomenon is called Crabtree Effect and has been described in two forms, long-term and short-term Effect. We have previously studied under fully controlled aerobic conditions forty yeast species for their central carbon metabolism and the presence of long-term Crabtree Effect. We have also studied ten steady-state yeast cultures, pulsed them with glucose, and followed the central carbon metabolism and the appearance of ethanol at dynamic conditions. In this paper we analyzed those wet laboratory data to elucidate possible mechanisms that determine the fate of glucose in different yeast species that cover approximately 250 million years of evolutionary history. We determine overflow metabolism to be the fundamental mechanism behind both long- and short-term Crabtree Effect, which originated approximately 125–150 million years ago in the Saccharomyces lineage. The “invention” of overflow metabolism was the first step in the evolution of aerobic fermentation in yeast. It provides a general strategy to increase energy production rates, which we show is positively correlated to growth. The “invention” of overflow has also simultaneously enabled rapid glucose consumption in yeast, which is a trait that could have been selected for, to “starve” competitors in nature. We also show that glucose repression of respiration is confined mainly among S. cerevisiae and closely related species that diverged after the whole genome duplication event, less than 100 million years ago. Thus, glucose repression of respiration was apparently “invented” as a second step to further increase overflow and ethanol production, to inhibit growth of other microbes. The driving force behind the initial evolutionary steps was most likely competition with other microbes to faster consume and convert sugar into biomass, in niches that were semi-anaerobic.
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Evolutionary scenario for the origin of Crabtree Effect in Saccharomycetales yeast.
2015Co-Authors: Arne Hagman, Jure PiškurAbstract:This figure illustrates the capacity of central carbon metabolic pathways for the metabolic groups of yeast (as designated in Table 1), when grown on C6-sugars such as glucose. Biomass formation rates have been left out, since no significant differences amongst groups could be observed (S2 Table). (A) Purely respiring yeasts, including Pichia, Debaromyces, Eremothecium and a majority of Kluyveromyces exhibited low glycolytic flux (GF), without any overflow metabolism (see also S10B Fig.). (B) Yeast that separated from the Eremothecium lineage, including some Kluyveromyces, and all Lachancea, Torulaspora, Zygotorulaspora and the majority of WGD yeasts possessed a greater glycolytic flux than respiratory flux (RF) capacity, what results in overflow metabolism. The upregulation of the anaerobic glycolysis has provided this group of yeast with a greater energy producing apparatus that can consume glucose more rapidly under aerobic conditions (see also S10C Fig.). (C) Our results can be interpreted as that traits such as overconsumption of glucose, and excess of energy producing capacity has enabled the development of a third metabolic group (including a majority of Kazachstania and Saccharomyces) that exhibit a trade-off between ethanol and energy production efficiency (see also S10D Fig.).
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analysis of the yeast short term Crabtree Effect and its origin
FEBS Journal, 2014Co-Authors: Arne Hagman, Torbjorn Sall, Jure PiškurAbstract:The short-term Crabtree Effect is defined as the immediate occurrence of aerobic alcoholic fermentation in response to provision of a pulse of excess sugar to sugar-limited yeast cultures. Here we have characterized ten yeast species with a clearly defined phylogenetic relationship. Yeast species were cultivated under glucose-limited conditions, and we studied their general carbon metabolism in response to a glucose pulse. We generated an extensive collection of data on glucose and oxygen consumption, and ethanol and carbon dioxide generation. We conclude that the Pichia, Debaryomyces, Eremothecium and Kluyveromyces marxianus yeasts do not exhibit any significant ethanol formation, while Kluyveromyces lactis behaves as an intermediate yeast, and Lachancea, Torulaspora, Vanderwaltozyma and Saccharomyces yeasts exhibit rapid ethanol accumulation. Based on the present data and our previous data relating to the presence of the long-term Crabtree Effect in over 40 yeast species, we speculate that the origin of the short-term Effect may coincide with the origin of the long-term Crabtree Effect in the Saccharomycetales lineage, occurring ~ 150 million years ago.
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Yeast "make-accumulate-consume" life strategy evolved as a multi-step process that predates the whole genome duplication
'Public Library of Science (PLoS)', 2013Co-Authors: Arne Hagman, Concetta Compagno, T. Sä, Jure PiškurAbstract:When fruits ripen, microbial communities start a fierce competition for the freely available fruit sugars. Three yeast lineages, including baker's yeast Saccharomyces cerevisiae, have independently developed the metabolic activity to convert simple sugars into ethanol even under fully aerobic conditions. This fermentation capacity, named Crabtree Effect, reduces the cell-biomass production but provides in nature a tool to out-compete other microorganisms. Here, we analyzed over forty Saccharomycetaceae yeasts, covering over 200 million years of the evolutionary history, for their carbon metabolism. The experiments were done under strictly controlled and uniform conditions, which has not been done before. We show that the origin of Crabtree Effect in Saccharomycetaceae predates the whole genome duplication and became a settled metabolic trait after the split of the S. cerevisiae and Kluyveromyces lineages, and coincided with the origin of modern fruit bearing plants. Our results suggest that ethanol fermentation evolved progressively, involving several successive molecular events that have gradually remodeled the yeast carbon metabolism. While some of the final evolutionary events, like gene duplications of glucose transporters and glycolytic enzymes, have been deduced, the earliest molecular events initiating Crabtree Effect are still to be determined
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Yeast ‘‘Make-Accumulate-Consume’ ’ Life Strategy Evolved as a Multi-Step Process That Predates the Whole Genome Duplication
2013Co-Authors: Arne Hagman, Concetta Compagno, Jure PiškurAbstract:When fruits ripen, microbial communities start a fierce competition for the freely available fruit sugars. Three yeast lineages, including baker’s yeast Saccharomyces cerevisiae, have independently developed the metabolic activity to convert simple sugars into ethanol even under fully aerobic conditions. This fermentation capacity, named Crabtree Effect, reduces the cell-biomass production but provides in nature a tool to out-compete other microorganisms. Here, we analyzed over forty Saccharomycetaceae yeasts, covering over 200 million years of the evolutionary history, for their carbon metabolism. The experiments were done under strictly controlled and uniform conditions, which has not been done before. We show that the origin of Crabtree Effect in Saccharomycetaceae predates the whole genome duplication and became a settled metabolic trait after the split of the S. cerevisiae and Kluyveromyces lineages, and coincided with the origin of modern fruit bearing plants. Our results suggest that ethanol fermentation evolved progressively, involving several successive molecular events that have gradually remodeled the yeast carbon metabolism. While some of the final evolutionary events, like gene duplications of glucose transporters and glycolytic enzymes, have been deduced, the earliest molecular events initiatin
Martin M Knight - One of the best experts on this subject based on the ideXlab platform.
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both superficial and deep zone articular chondrocyte subpopulations exhibit the Crabtree Effect but have different basal oxygen consumption rates
Journal of Cellular Physiology, 2010Co-Authors: Hannah K Heywood, Martin M Knight, David A LeeAbstract:In the absence of in vivo measurements, the oxygen concentration within articular cartilage is calculated from the balance between cellular oxygen consumption and mass transfer. Current estimates of the oxygen tension within articular cartilage are based on oxygen consumption data from full-depth tissue samples. However, superficial and deep cell subpopulations of articular cartilage express intrinsic metabolic differences. We test the hypothesis that the subpopulations differ with respect to their intrinsic oxygen consumption rate. Chondrocytes from the full cartilage thickness demonstrate enhanced oxygen consumption when deprived of glucose, consistent with the Crabtree phenomena. Chondrocyte subpopulations differ in the prevailing availability of oxygen and glucose, which decrease with distance from the cartilage-synovial fluid interface. Thus, we tested the hypothesis that the oxygen consumption of each subpopulation is modulated by nutrient availability, by examining the expression of the Crabtree Effect. The deep cells had a greater oxygen consumption than the superficial cells (V(max) of 6.6 compared to 3.2 fmol/cell/h), consistent with our observations of mitochondrial volume (mean values 52.0 vs. 36.4 microm(3)/cell). Both populations expressed the Crabtree phenomena, with oxygen consumption increasing approximately 2.5-fold in response to glycolytic inhibition by glucose deprivation or 2-deoxyglucose. Over 90% of this increase was oligomycin-sensitive and thus accounted for by oxidative phosphorylation. The data contributes towards our understanding of chondrocyte energy metabolism and provides information valuable for the accurate calculation of the oxygen concentration that the cells experience in vivo. The work has further application to the optimisation of bioreactor design and engineered tissues.
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both superficial and deep zone articular chondrocyte subpopulations exhibit the Crabtree Effect but have different basal oxygen consumption rates
Journal of Cellular Physiology, 2010Co-Authors: Hannah K Heywood, Martin M KnightAbstract:In the absence of in vivo measurements, the oxygen concentration within articular cartilage is calculated from the balance between cellular oxygen consumption and mass transfer. Current estimates of the oxygen tension within articular cartilage are based on oxygen consumption data from full-depth tissue samples. However, superficial and deep cell subpopulations of articular cartilage express intrinsic metabolic differences. We test the hypothesis that the subpopulations differ with respect to their intrinsic oxygen consumption rate. Chondrocytes from the full cartilage thickness demonstrate enhanced oxygen consumption when deprived of glucose, consistent with the Crabtree phenomena. Chondrocyte subpopulations differ in the prevailing availability of oxygen and glucose, which decrease with distance from the cartilage–synovial fluid interface. Thus, we tested the hypothesis that the oxygen consumption of each subpopulation is modulated by nutrient availability, by examining the expression of the Crabtree Effect. The deep cells had a greater oxygen consumption than the superficial cells (Vmax of 6.6 compared to 3.2 fmol/cell/h), consistent with our observations of mitochondrial volume (mean values 52.0 vs. 36.4 µm3/cell). Both populations expressed the Crabtree phenomena, with oxygen consumption increasing ∼2.5-fold in response to glycolytic inhibition by glucose deprivation or 2-deoxyglucose. Over 90% of this increase was oligomycin-sensitive and thus accounted for by oxidative phosphorylation. The data contributes towards our understanding of chondrocyte energy metabolism and provides information valuable for the accurate calculation of the oxygen concentration that the cells experience in vivo. The work has further application to the optimisation of bioreactor design and engineered tissues. J. Cell. Physiol. 223:630–639, 2010. © 2010 Wiley-Liss, Inc.
Yuri V Evtodienko - One of the best experts on this subject based on the ideXlab platform.
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Effect of glucose and deoxyglucose on the redistribution of calcium in ehrlich ascites tumour and zajdela hepatoma cells and its consequences for mitochondrial energetics further arguments for the role of ca 2 in the mechanism of the Crabtree Effect
FEBS Journal, 1999Co-Authors: Lech Wojtczak, V V Teplova, Krystyna Bogucka, Jerzy Duszynski, Aneta Czyz, Agnieszka Makowska, Mariusz R Wieckowski, Yuri V EvtodienkoAbstract:The distribution of Ca2+ in intact cells was monitored with fluorescent probes: fura-2 for cytosolic [Ca2+] and rhod-2 for mitochondrial [Ca2+]. It was found that in neoplastic cells, such as Ehrlich ascites tumour and Zajdela hepatoma, but not in non-malignant cells, such as fibroblasts, glucose and deoxyglucose elicited release of Ca2+ from endoplasmic reticulum stores and an increase in Ca2+ concentration in the cytosol. Parallel to this, a decrease in the rate of Ca2+ extrusion from the cell and an enhanced uptake of Ca2+ by mitochondria were observed. The increase in mitochondrial [Ca2+] was accompanied by an increase in the mitochondrial membrane potential and the reduction state of nicotinamide nucleotides. F1Fo-ATPase in submitochondrial particles of Zajdela hepatoma was strongly inhibited in the presence of micromolar Ca2+ concentrations, whereas this activity in submitochondrial particles from rat liver appeared to be less sensitive to Ca2+. Indications of glycosylation of Ehrlich ascites tumour cell proteins were also obtained. These data strengthen the proposal [Bogucka, K., Teplova, V.V., Wojtczak, L. and Evtodienko, Y. V. (1995) Biochim. Biophys. Acta1228, 261–266] that the Crabtree Effect is produced by mobilization of cell calcium, which is subsequently taken up by mitochondria and inhibits F1Fo-ATP synthase.
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inhibition by ca2 of the hydrolysis and the synthesis of atp in ehrlich ascites tumour mitochondria relation to the Crabtree Effect
Biochimica et Biophysica Acta, 1995Co-Authors: Krystyna Bogucka, V V Teplova, Lech Wojtczaka, Yuri V EvtodienkoAbstract:Abstract Phosphorylation of ADP and hydrolysis of ATP by isolated mitochondria from Ehrlich ascites tumuor cells is greatly reduced when the mitochondria have been preloaded with Ca2+ (50 nmol/mg protein or more). Translocation of ADP is diminished in Ca2+-loaded mitochondria. However, ATPase in toluene-permeabilized mitochondria and in inside-out submitochondrial particles is also strongly inhibited by micromolar concentrations of Ca2+, indicating that, independently of adenine nucleotide transport, F1F0-ATPase is also affected. ATP hydrolysis by submitochondrial particles depleted of the inhibitory subunit of F1F0-ATPase is also inhibitor) is insensitive to Ca2+; however, this sensitivity is restored when the particles are supplemented with the inhibitory subunit isolated from beef heart mitochondria. In view of the previous observations that glucose elicits in Ehrlich ascites tumour cells an increase of cytoplasmic free Ca2+ (Teplova, V.V., Bogucka, K., Czy/.z, A., Evtodienko, YuV., Duszynski, J. and Wojtczak, L. (1003) Biochem. Biophys. Res. Commun. 196, 1148–1154) and that this calcium is then taken up by mitochondria, resulting in a strong inhibition of coupled respiration (Evtodienko, Yu.V.,Teplova, V.V., Duszynski, J., Bogucka, K. and Wojtczak, L. (1994) Cell Calcium 15, 439–446), the present results are discussed in terms of the mechanism of the Crabtree Effect in tumour cells.
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the role of cytoplasmic ca2 in glucose induced inhibition of respiration and oxidative phosphorylation in ehrlich ascites tumour cells a novel mechanism of the Crabtree Effect
Cell Calcium, 1994Co-Authors: Yuri V Evtodienko, V V Teplova, Krystyna Bogucka, Jerzy Duszynski, Lech WojtczakAbstract:Abstract The Effect of Ca2+ on energy-coupling parameters of Ehrlich ascites carcinoma was studied in digitonin-permeabilized cells. In nominally Ca-free medium the permeabilized cells respond to the addition of ADP by increased oxygen uptake with externally added respiratory substrates (succinate or pyruvate), decrease of the mitochondrial membrane potential (Δψ) and alkalinization of the medium. This typical behaviour is drastically changed if Ca2+ is added. The subsequent addition of ADP induces neither State 3 respiration, nor decrease of Δψ, nor alkalinization of the medium, indicating a complete block of ATP synthesis. These Effects are produced by both a single pulse of 100 μM Ca2+ and a preincubation for 2 min with 0.4–1.0 μM Ca2+. Preincubation of the cells with glucose or deoxyglucose prior to permeabilization makes them sensitive to Ca2+ concentrations as low as 0.3 μM. In view of the previous finding that glucose and deoxyglucose produce an increase of cytoplasmic [Ca2+] in Ehrlich ascites cells [Teplova VV. Bogucka K. Czyz A. Evtodienko YuV. Duszynski J. Wojtczak L. (1993) Biochem. Biophys. Res. Commun., 196, 1148–1154; Czyz A. Teplova VV. Sabala P. Czarny M. Evtodienko YuV. Wojtczak L. (1993) Acta Biochim. Polon., 40, 539–544], the present results suggest that cytoplasmic Ca2+ plays a crucial role in the Crabtree Effect.
Arne Hagman - One of the best experts on this subject based on the ideXlab platform.
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a study on the fundamental mechanism and the evolutionary driving forces behind aerobic fermentation in yeast
PLOS ONE, 2015Co-Authors: Arne Hagman, Jure PiškurAbstract:Baker’s yeast Saccharomyces cerevisiae rapidly converts sugars to ethanol and carbon dioxide at both anaerobic and aerobic conditions. The later phenomenon is called Crabtree Effect and has been described in two forms, long-term and short-term Effect. We have previously studied under fully controlled aerobic conditions forty yeast species for their central carbon metabolism and the presence of long-term Crabtree Effect. We have also studied ten steady-state yeast cultures, pulsed them with glucose, and followed the central carbon metabolism and the appearance of ethanol at dynamic conditions. In this paper we analyzed those wet laboratory data to elucidate possible mechanisms that determine the fate of glucose in different yeast species that cover approximately 250 million years of evolutionary history. We determine overflow metabolism to be the fundamental mechanism behind both long- and short-term Crabtree Effect, which originated approximately 125–150 million years ago in the Saccharomyces lineage. The “invention” of overflow metabolism was the first step in the evolution of aerobic fermentation in yeast. It provides a general strategy to increase energy production rates, which we show is positively correlated to growth. The “invention” of overflow has also simultaneously enabled rapid glucose consumption in yeast, which is a trait that could have been selected for, to “starve” competitors in nature. We also show that glucose repression of respiration is confined mainly among S. cerevisiae and closely related species that diverged after the whole genome duplication event, less than 100 million years ago. Thus, glucose repression of respiration was apparently “invented” as a second step to further increase overflow and ethanol production, to inhibit growth of other microbes. The driving force behind the initial evolutionary steps was most likely competition with other microbes to faster consume and convert sugar into biomass, in niches that were semi-anaerobic.
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Evolutionary scenario for the origin of Crabtree Effect in Saccharomycetales yeast.
2015Co-Authors: Arne Hagman, Jure PiškurAbstract:This figure illustrates the capacity of central carbon metabolic pathways for the metabolic groups of yeast (as designated in Table 1), when grown on C6-sugars such as glucose. Biomass formation rates have been left out, since no significant differences amongst groups could be observed (S2 Table). (A) Purely respiring yeasts, including Pichia, Debaromyces, Eremothecium and a majority of Kluyveromyces exhibited low glycolytic flux (GF), without any overflow metabolism (see also S10B Fig.). (B) Yeast that separated from the Eremothecium lineage, including some Kluyveromyces, and all Lachancea, Torulaspora, Zygotorulaspora and the majority of WGD yeasts possessed a greater glycolytic flux than respiratory flux (RF) capacity, what results in overflow metabolism. The upregulation of the anaerobic glycolysis has provided this group of yeast with a greater energy producing apparatus that can consume glucose more rapidly under aerobic conditions (see also S10C Fig.). (C) Our results can be interpreted as that traits such as overconsumption of glucose, and excess of energy producing capacity has enabled the development of a third metabolic group (including a majority of Kazachstania and Saccharomyces) that exhibit a trade-off between ethanol and energy production efficiency (see also S10D Fig.).
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analysis of the yeast short term Crabtree Effect and its origin
FEBS Journal, 2014Co-Authors: Arne Hagman, Torbjorn Sall, Jure PiškurAbstract:The short-term Crabtree Effect is defined as the immediate occurrence of aerobic alcoholic fermentation in response to provision of a pulse of excess sugar to sugar-limited yeast cultures. Here we have characterized ten yeast species with a clearly defined phylogenetic relationship. Yeast species were cultivated under glucose-limited conditions, and we studied their general carbon metabolism in response to a glucose pulse. We generated an extensive collection of data on glucose and oxygen consumption, and ethanol and carbon dioxide generation. We conclude that the Pichia, Debaryomyces, Eremothecium and Kluyveromyces marxianus yeasts do not exhibit any significant ethanol formation, while Kluyveromyces lactis behaves as an intermediate yeast, and Lachancea, Torulaspora, Vanderwaltozyma and Saccharomyces yeasts exhibit rapid ethanol accumulation. Based on the present data and our previous data relating to the presence of the long-term Crabtree Effect in over 40 yeast species, we speculate that the origin of the short-term Effect may coincide with the origin of the long-term Crabtree Effect in the Saccharomycetales lineage, occurring ~ 150 million years ago.
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Yeast "make-accumulate-consume" life strategy evolved as a multi-step process that predates the whole genome duplication
'Public Library of Science (PLoS)', 2013Co-Authors: Arne Hagman, Concetta Compagno, T. Sä, Jure PiškurAbstract:When fruits ripen, microbial communities start a fierce competition for the freely available fruit sugars. Three yeast lineages, including baker's yeast Saccharomyces cerevisiae, have independently developed the metabolic activity to convert simple sugars into ethanol even under fully aerobic conditions. This fermentation capacity, named Crabtree Effect, reduces the cell-biomass production but provides in nature a tool to out-compete other microorganisms. Here, we analyzed over forty Saccharomycetaceae yeasts, covering over 200 million years of the evolutionary history, for their carbon metabolism. The experiments were done under strictly controlled and uniform conditions, which has not been done before. We show that the origin of Crabtree Effect in Saccharomycetaceae predates the whole genome duplication and became a settled metabolic trait after the split of the S. cerevisiae and Kluyveromyces lineages, and coincided with the origin of modern fruit bearing plants. Our results suggest that ethanol fermentation evolved progressively, involving several successive molecular events that have gradually remodeled the yeast carbon metabolism. While some of the final evolutionary events, like gene duplications of glucose transporters and glycolytic enzymes, have been deduced, the earliest molecular events initiating Crabtree Effect are still to be determined
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Yeast ‘‘Make-Accumulate-Consume’ ’ Life Strategy Evolved as a Multi-Step Process That Predates the Whole Genome Duplication
2013Co-Authors: Arne Hagman, Concetta Compagno, Jure PiškurAbstract:When fruits ripen, microbial communities start a fierce competition for the freely available fruit sugars. Three yeast lineages, including baker’s yeast Saccharomyces cerevisiae, have independently developed the metabolic activity to convert simple sugars into ethanol even under fully aerobic conditions. This fermentation capacity, named Crabtree Effect, reduces the cell-biomass production but provides in nature a tool to out-compete other microorganisms. Here, we analyzed over forty Saccharomycetaceae yeasts, covering over 200 million years of the evolutionary history, for their carbon metabolism. The experiments were done under strictly controlled and uniform conditions, which has not been done before. We show that the origin of Crabtree Effect in Saccharomycetaceae predates the whole genome duplication and became a settled metabolic trait after the split of the S. cerevisiae and Kluyveromyces lineages, and coincided with the origin of modern fruit bearing plants. Our results suggest that ethanol fermentation evolved progressively, involving several successive molecular events that have gradually remodeled the yeast carbon metabolism. While some of the final evolutionary events, like gene duplications of glucose transporters and glycolytic enzymes, have been deduced, the earliest molecular events initiatin
V V Teplova - One of the best experts on this subject based on the ideXlab platform.
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Effect of glucose and deoxyglucose on the redistribution of calcium in ehrlich ascites tumour and zajdela hepatoma cells and its consequences for mitochondrial energetics further arguments for the role of ca 2 in the mechanism of the Crabtree Effect
FEBS Journal, 1999Co-Authors: Lech Wojtczak, V V Teplova, Krystyna Bogucka, Jerzy Duszynski, Aneta Czyz, Agnieszka Makowska, Mariusz R Wieckowski, Yuri V EvtodienkoAbstract:The distribution of Ca2+ in intact cells was monitored with fluorescent probes: fura-2 for cytosolic [Ca2+] and rhod-2 for mitochondrial [Ca2+]. It was found that in neoplastic cells, such as Ehrlich ascites tumour and Zajdela hepatoma, but not in non-malignant cells, such as fibroblasts, glucose and deoxyglucose elicited release of Ca2+ from endoplasmic reticulum stores and an increase in Ca2+ concentration in the cytosol. Parallel to this, a decrease in the rate of Ca2+ extrusion from the cell and an enhanced uptake of Ca2+ by mitochondria were observed. The increase in mitochondrial [Ca2+] was accompanied by an increase in the mitochondrial membrane potential and the reduction state of nicotinamide nucleotides. F1Fo-ATPase in submitochondrial particles of Zajdela hepatoma was strongly inhibited in the presence of micromolar Ca2+ concentrations, whereas this activity in submitochondrial particles from rat liver appeared to be less sensitive to Ca2+. Indications of glycosylation of Ehrlich ascites tumour cell proteins were also obtained. These data strengthen the proposal [Bogucka, K., Teplova, V.V., Wojtczak, L. and Evtodienko, Y. V. (1995) Biochim. Biophys. Acta1228, 261–266] that the Crabtree Effect is produced by mobilization of cell calcium, which is subsequently taken up by mitochondria and inhibits F1Fo-ATP synthase.
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biological role and mechanisms of realization of the Crabtree Effect in rapidly proliferating cells the role of ca2 ions
Biochemistry, 1996Co-Authors: Evtodienko Iuv, V V TeplovaAbstract:Characteristic differences in energy supply systems in normal differentiated cells versus rapidly proliferating cells including tumor cells are summarized. Previously suggested mechanisms of the Crabtree Effect (inhibition of respiration by glycolysis metabolites) are specifically evaluated. The Effect cannot be explained by the competition of glycolysis systems with oxidative phosphorylation for ADP and Pi. A novel mechanism of the Crabtree Effect is suggested based on regulatory (inhibitory) Effect of Ca2+ as the second messenger on oxidative phosphorylation in tumor cells and other rapidly proliferating cells. The Crabtree Effect can be one of the main mechanisms which switch cellular energy metabolism form oxidation to anaerobic glycolysis, the latter being more beneficial for reductive biosynthetic reactions and rapid growth of the cells.
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inhibition by ca2 of the hydrolysis and the synthesis of atp in ehrlich ascites tumour mitochondria relation to the Crabtree Effect
Biochimica et Biophysica Acta, 1995Co-Authors: Krystyna Bogucka, V V Teplova, Lech Wojtczaka, Yuri V EvtodienkoAbstract:Abstract Phosphorylation of ADP and hydrolysis of ATP by isolated mitochondria from Ehrlich ascites tumuor cells is greatly reduced when the mitochondria have been preloaded with Ca2+ (50 nmol/mg protein or more). Translocation of ADP is diminished in Ca2+-loaded mitochondria. However, ATPase in toluene-permeabilized mitochondria and in inside-out submitochondrial particles is also strongly inhibited by micromolar concentrations of Ca2+, indicating that, independently of adenine nucleotide transport, F1F0-ATPase is also affected. ATP hydrolysis by submitochondrial particles depleted of the inhibitory subunit of F1F0-ATPase is also inhibitor) is insensitive to Ca2+; however, this sensitivity is restored when the particles are supplemented with the inhibitory subunit isolated from beef heart mitochondria. In view of the previous observations that glucose elicits in Ehrlich ascites tumour cells an increase of cytoplasmic free Ca2+ (Teplova, V.V., Bogucka, K., Czy/.z, A., Evtodienko, YuV., Duszynski, J. and Wojtczak, L. (1003) Biochem. Biophys. Res. Commun. 196, 1148–1154) and that this calcium is then taken up by mitochondria, resulting in a strong inhibition of coupled respiration (Evtodienko, Yu.V.,Teplova, V.V., Duszynski, J., Bogucka, K. and Wojtczak, L. (1994) Cell Calcium 15, 439–446), the present results are discussed in terms of the mechanism of the Crabtree Effect in tumour cells.
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the role of cytoplasmic ca2 in glucose induced inhibition of respiration and oxidative phosphorylation in ehrlich ascites tumour cells a novel mechanism of the Crabtree Effect
Cell Calcium, 1994Co-Authors: Yuri V Evtodienko, V V Teplova, Krystyna Bogucka, Jerzy Duszynski, Lech WojtczakAbstract:Abstract The Effect of Ca2+ on energy-coupling parameters of Ehrlich ascites carcinoma was studied in digitonin-permeabilized cells. In nominally Ca-free medium the permeabilized cells respond to the addition of ADP by increased oxygen uptake with externally added respiratory substrates (succinate or pyruvate), decrease of the mitochondrial membrane potential (Δψ) and alkalinization of the medium. This typical behaviour is drastically changed if Ca2+ is added. The subsequent addition of ADP induces neither State 3 respiration, nor decrease of Δψ, nor alkalinization of the medium, indicating a complete block of ATP synthesis. These Effects are produced by both a single pulse of 100 μM Ca2+ and a preincubation for 2 min with 0.4–1.0 μM Ca2+. Preincubation of the cells with glucose or deoxyglucose prior to permeabilization makes them sensitive to Ca2+ concentrations as low as 0.3 μM. In view of the previous finding that glucose and deoxyglucose produce an increase of cytoplasmic [Ca2+] in Ehrlich ascites cells [Teplova VV. Bogucka K. Czyz A. Evtodienko YuV. Duszynski J. Wojtczak L. (1993) Biochem. Biophys. Res. Commun., 196, 1148–1154; Czyz A. Teplova VV. Sabala P. Czarny M. Evtodienko YuV. Wojtczak L. (1993) Acta Biochim. Polon., 40, 539–544], the present results suggest that cytoplasmic Ca2+ plays a crucial role in the Crabtree Effect.
