In this work, the effect of moderate electromagnetic fields (2.5, 10, and 15 mT) was studied using an immersed coil inserted directly into a bioreactor on batch cultivation of yeast under both aerobic and anaerobic conditions. Throughout the cultivation, parameters, including CO2 levels, O2 saturation, nitrogen consumption, glucose uptake, ethanol production, and yeast growth (using OD 600 measurements at 1-h intervals), were analysed. The results showed that 10 and 15 mT magnetic fields not only statistically significantly boosted and sped up biomass production (by 38-70%), but also accelerated overall metabolism, accelerating glucose, oxygen, and nitrogen consumption, by 1-2 h. The carbon balance analysis revealed an acceleration in ethanol and glycerol production, albeit with final concentrations by 22-28% lower, with a more pronounced effect in aerobic cultivation. These findings suggest that magnetic fields shift the metabolic balance toward biomass formation rather than ethanol production, showcasing their potential to modulate yeast metabolism. Considering coil heating, opting for the 10 mT magnetic field is preferable due to its lower heat generation. In these terms, we propose that magnetic field can be used as novel tool to increase biomass yield and accelerate yeast metabolism.
- Klíčová slova
- Aerobic, Anaerobic, Batch fermentation, Biomass, Magnetic field, Metabolism acceleration, Yeast,
- MeSH
- aerobióza MeSH
- anaerobióza MeSH
- biomasa * MeSH
- bioreaktory mikrobiologie MeSH
- dusík metabolismus MeSH
- ethanol * metabolismus MeSH
- fermentace * MeSH
- glukosa metabolismus MeSH
- glycerol metabolismus MeSH
- kyslík metabolismus MeSH
- magnetické pole * MeSH
- Saccharomyces cerevisiae * metabolismus růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- dusík MeSH
- ethanol * MeSH
- glukosa MeSH
- glycerol MeSH
- kyslík MeSH
The application of pulsed electric fields (PEFs) is becoming a promising tool for application in biotechnology, and the food industry. However, real-time monitoring of the efficiency of PEF treatment conditions is challenging, especially at the industrial scale and in continuous production conditions. To overcome this challenge, we have developed a straightforward setup capable of real-time detection of yeast biological autoluminescence (BAL) during pulsing. Saccharomyces cerevisiae culture was exposed to 8 pulses of 100 µs width with electric field strength magnitude 2-7 kV cm-1. To assess the sensitivity of our method in detecting yeast electroporation, we conducted a comparison with established methods including impedance measurements, propidium iodide uptake, cell growth assay, and fluorescence microscopy. Our results demonstrate that yeast electroporation can be instantaneously monitored during pulsing, making it highly suitable for industrial applications. Furthermore, the simplicity of our setup facilitates its integration into continuous liquid flow systems. Additionally, we have established quantitative indicators based on a thorough statistical analysis of the data that can be implemented through a dedicated machine interface, providing efficiency indicators for analysis.
- Klíčová slova
- autoluminescence, electroporation, pulsed electric fields, yeast in biotechnology,
- MeSH
- elektroporace * metody MeSH
- Saccharomyces cerevisiae * růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
The existence of programmed cell death in Saccharomyces cerevisiae has been reported for many years. Glucose induces the death of S. cerevisiae in the absence of additional nutrients within a few hours, and the absence of active potassium uptake makes cells highly sensitive to this process. S. cerevisiae cells possess two transporters, Trk1 and Trk2, which ensure a high intracellular concentration of potassium, necessary for many physiological processes. Trk1 is the major system responsible for potassium acquisition in growing and dividing cells. The contribution of Trk2 to potassium uptake in growing cells is almost negligible, but Trk2 becomes crucial for stationary cells for their survival of some stresses, e.g. anhydrobiosis. As a new finding, we show that both Trk systems contribute to the relative thermotolerance of S. cerevisiae BY4741. Our results also demonstrate that Trk2 is much more important for the cell survival of glucose-induced cell death than Trk1, and that stationary cells deficient in active potassium uptake lose their ATP stocks more rapidly than cells with functional Trk systems. This is probably due to the upregulated activity of plasma-membrane Pma1 H+-ATPase, and consequently, it is the reason why these cells die earlier than cells with functional active potassium uptake.
- Klíčová slova
- ATP content, GICD, Saccharomyces cerevisiae, potassium uptake, stationary cells, thermotolerance,
- MeSH
- buněčná smrt MeSH
- draslík metabolismus MeSH
- glukosa metabolismus MeSH
- mikrobiální viabilita MeSH
- proteiny přenášející kationty genetika metabolismus MeSH
- Saccharomyces cerevisiae - proteiny genetika metabolismus MeSH
- Saccharomyces cerevisiae cytologie růst a vývoj metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- draslík MeSH
- glukosa MeSH
- proteiny přenášející kationty MeSH
- Saccharomyces cerevisiae - proteiny MeSH
- TRK1 protein, S cerevisiae MeSH Prohlížeč
- TRK2 protein, S cerevisiae MeSH Prohlížeč
Nowadays, modern medicine is looking for new, more gentle, and more efficient diagnostic methods. A pathological state of an organism is often closely connected with increased amount of reactive oxygen species. They can react with biomolecules and subsequent reactions can lead to very low endogenous light emission (biological autoluminescence-BAL). This phenomenon can be potentially used as a non-invasive and low-operational-cost tool for monitoring oxidative stress during diseases. To contribute to the understanding of the parameters affecting BAL, we analyzed the BAL from yeast Saccharomyces cerevisiae as a representative eukaryotic organism. The relationship between the BAL intensity and the amount of reactive oxygen species that originates as a result of the Fenton reaction as well as correlation between spontaneous BAL and selected physical and chemical parameters (pH, oxygen partial pressure, and cell concentration) during cell growth were established. Our results contribute to real-time non-invasive methodologies for monitoring oxidative processes in biomedicine and biotechnology.
Stress granules (SGs) are membrane-less assemblies arising upon various stresses in eukaryotic cells. They sequester mRNAs and proteins from stressful conditions and modulate gene expression to enable cells to resume translation and growth after stress relief. SGs containing the translation initiation factor eIF3a/Rpg1 arise in yeast cells upon robust heat shock (HS) at 46 °C only. We demonstrate that the destabilization of Rpg1 within the PCI domain in the Rpg1-3 variant leads to SGs assembly already at moderate HS at 42 °C. These are bona fide SGs arising upon translation arrest containing mRNAs, which are components of the translation machinery, and associating with P-bodies. HS SGs associate with endoplasmatic reticulum and mitochondria and their contact sites ERMES. Although Rpg1-3-labeled SGs arise at a lower temperature, their disassembly is delayed after HS at 46 °C. Remarkably, the delayed disassembly of HS SGs after the robust HS is reversed by TDP-43, which is a human protein connected with amyotrophic lateral sclerosis. TDP-43 colocalizes with HS SGs in yeast cells and facilitates cell regrowth after the stress relief. Based on our results, we propose yeast HS SGs labeled by Rpg1 and its variants as a novel model system to study functions of TDP-43 in stress granules disassembly.
- Klíčová slova
- ER, ERMES, Hsp104, Rpg1, TDP-43, eIF3, heat shock, mitochondria, stress granules, yeast,
- MeSH
- cytoplazmatická granula fyziologie MeSH
- DNA vazebné proteiny genetika metabolismus MeSH
- endoplazmatické retikulum metabolismus MeSH
- eukaryotický iniciační faktor 3 chemie genetika metabolismus MeSH
- lidé MeSH
- messenger RNA genetika metabolismus MeSH
- mitochondrie metabolismus MeSH
- reakce na tepelný šok * MeSH
- Saccharomyces cerevisiae - proteiny genetika metabolismus MeSH
- Saccharomyces cerevisiae genetika růst a vývoj metabolismus MeSH
- stabilita proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- DNA vazebné proteiny MeSH
- EIF3A protein, human MeSH Prohlížeč
- eukaryotický iniciační faktor 3 MeSH
- messenger RNA MeSH
- RPG1 protein, S cerevisiae MeSH Prohlížeč
- Saccharomyces cerevisiae - proteiny MeSH
- TARDBP protein, human MeSH Prohlížeč
Superabsorbent polymers (SAPs) are most often used in hygienic goods or in the agricultural sector but the range of their application is much broader, including the utilization in advanced building materials. Although SAPs were studied widely during the last decades, the data related to the interactions between the natural environment and various organisms occurring on their surface are still lacking. In addition, SAPs can create a variable gel-forming matter in the presence of water but standard ecotoxicological bioassays are mostly not suitable for testing such type of materials. In this study, the SAPs potential for reducing/supporting unwanted indoor microorganism settlement was analyzed by biological methods under controlled laboratory conditions. Three commonly used SAPs (Cabloc CT, Creasorb SIS, Hydropam) were exposed to selected organisms representing green algae (Hematococcus pluvialis), cyanobacteria (Nostoc sp.), yeasts (Saccharomyces cerevisiae), wood-destroying fungi (Gleophyllium trabeum), and aerial molds. The obtained results indicated that Hydropam provided favorable conditions for Hematococcus pluvialis, Nostoc sp., and Saccharomyces cerevisiae. All three tested SAPs inhibited, both with and without nutrient addition, the growth of Gleophyllium trabeum and aerial molds.
- Klíčová slova
- Algae, Cyanobacteria, Fungi, Molds, Superabsorbent polymers, Yeasts,
- MeSH
- akrylamid chemie MeSH
- Chlorophyta růst a vývoj MeSH
- konstrukční materiály mikrobiologie MeSH
- lidé MeSH
- Nostoc růst a vývoj izolace a purifikace MeSH
- polymery chemie MeSH
- Saccharomyces cerevisiae růst a vývoj izolace a purifikace MeSH
- voda chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- akrylamid MeSH
- polymery MeSH
- voda MeSH
Yeast cells must grow to a critical size before committing to division. It is unknown how size is measured. We find that as cells grow, mRNAs for some cell-cycle activators scale faster than size, increasing in concentration, while mRNAs for some inhibitors scale slower than size, decreasing in concentration. Size-scaled gene expression could cause an increasing ratio of activators to inhibitors with size, triggering cell-cycle entry. Consistent with this, expression of the CLN2 activator from the promoter of the WHI5 inhibitor, or vice versa, interfered with cell size homeostasis, yielding a broader distribution of cell sizes. We suggest that size homeostasis comes from differential scaling of gene expression with size. Differential regulation of gene expression as a function of cell size could affect many cellular processes.
- Klíčová slova
- Cln3, cell cycle, cell cycle control, cell cycle regulation, cell size control, growth Whi5, growth control of division, size homeostasis, start, yeast cell cycle,
- MeSH
- buněčné dělení genetika MeSH
- buněčný cyklus genetika MeSH
- cykliny genetika MeSH
- G1 fáze genetika MeSH
- regulace genové exprese u hub genetika MeSH
- Saccharomyces cerevisiae - proteiny genetika MeSH
- Saccharomyces cerevisiae genetika růst a vývoj MeSH
- velikost buňky * MeSH
- vývojová regulace genové exprese genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- CLN2 protein, S cerevisiae MeSH Prohlížeč
- cykliny MeSH
- Saccharomyces cerevisiae - proteiny MeSH
Baker's yeast is a valuable model system for the study of biological aging as it can be utilized for the measurement of replicative and chronological life spans in response to interventions. Whereas replicative aging in Saccharomyces cerevisiae mirrors dividing mammalian cells, chronological aging is seen in non-dividing cells. Aging is strongly influenced by the cellular organelles, especially by mitochondria which house essential functions like oxidative phosphorylation. Additionally, peroxisomes were shown to modulate the aging process, mainly by their turnover of reactive oxygen species. There is a fundamental interest in understanding how mitochondria and peroxisomes contribute to cellular aging. This work analyzes chronological aging in yeast mutants that are affected in peroxisomal proliferation and inheritance. Deletion of INP1 (retention of peroxisomes in the mother cell) or PEX11 (division of peroxisomes) leads to clearly reduced life spans compared to the wild-type control under conditions which depend on peroxisomal metabolism. Δinp1 cells are long-lived in contrast to the wild type and Δpex11 when assayed under conditions that not necessitate peroxisome function. Neither treatment affects the index of respiratory capacity, indicating fully functional mitochondria. Evaluation of stress resistances reveals that Δinp1 has significantly higher resistance to the apoptosis elicitor acetic acid. Old Δpex11 cells from an oleate culture are more susceptible to hydrogen peroxide treatment compared to Δinp1 and the wild type. Finally, aged cells are hyper-sensitive to heat shock treatment in contrast to young cells.
- MeSH
- delece genu MeSH
- membránové proteiny genetika metabolismus MeSH
- mikrobiální viabilita MeSH
- peroxiny genetika metabolismus MeSH
- peroxizomy genetika metabolismus MeSH
- proliferace buněk MeSH
- reaktivní formy kyslíku metabolismus MeSH
- Saccharomyces cerevisiae - proteiny genetika metabolismus MeSH
- Saccharomyces cerevisiae genetika růst a vývoj metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- INP1 protein, S cerevisiae MeSH Prohlížeč
- membránové proteiny MeSH
- peroxiny MeSH
- PEX11 protein, S cerevisiae MeSH Prohlížeč
- reaktivní formy kyslíku MeSH
- Saccharomyces cerevisiae - proteiny MeSH
Translationally controlled tumor protein (TCTP) is a multifunctional and highly conserved protein from yeast to humans. Recently, its role in non-selective autophagy has been reported with controversial results in mammalian and human cells. Herein we examine the effect of Mmi1, the yeast ortholog of TCTP, on non-selective autophagy in budding yeast Saccharomyces cerevisiae, a well-established model system to monitor autophagy. We induced autophagy by nitrogen starvation or rapamycin addition and measured autophagy by using the Pho8Δ60 and GFP-Atg8 processing assays in WT, mmi1Δ, and in autophagy-deficient strains atg8Δ or atg1Δ. Our results demonstrate that Mmi1 does not affect basal or nitrogen starvation-induced autophagy. However, an increased rapamycin-induced autophagy is detected in mmi1Δ strain when the cells enter the post-diauxic growth phase, and this phenotype can be rescued by inserted wild-type MMI1 gene. Further, the mmi1Δ cells exhibit significantly lower amounts of reactive oxygen species (ROS) in the post-diauxic growth phase compared to WT cells. In summary, our study suggests that Mmi1 negatively affects rapamycin-induced autophagy in the post-diauxic growth phase and supports the role of Mmi1/TCTP as a negative autophagy regulator in eukaryotic cells.
- Klíčová slova
- Mmi1, TCTP, autophagy, nitrogen starvation, rapamycin, reactive oxygen species, translationally controlled tumor protein,
- MeSH
- autofagie * účinky léků MeSH
- dusík nedostatek MeSH
- glukosa farmakologie MeSH
- mutace genetika MeSH
- nádorové biomarkery chemie MeSH
- proteiny vázající vápník metabolismus MeSH
- Saccharomyces cerevisiae - proteiny metabolismus MeSH
- Saccharomyces cerevisiae cytologie účinky léků růst a vývoj MeSH
- sirolimus farmakologie MeSH
- superoxidy metabolismus MeSH
- translačně kontrolovaný nádorový protein 1 MeSH
- zelené fluorescenční proteiny metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- dusík MeSH
- glukosa MeSH
- nádorové biomarkery MeSH
- proteiny vázající vápník MeSH
- Saccharomyces cerevisiae - proteiny MeSH
- sirolimus MeSH
- superoxidy MeSH
- TMA19 protein, S cerevisiae MeSH Prohlížeč
- TPT1 protein, human MeSH Prohlížeč
- translačně kontrolovaný nádorový protein 1 MeSH
- zelené fluorescenční proteiny MeSH
Cells have elaborated a complex strategy to maintain protein homeostasis under physiological as well as stress conditions with the aim to ensure the smooth functioning of vital processes and producing healthy offspring. Impairment of one of the most important processes in living cells, translation, might have serious consequences including various brain disorders in humans. Here, we describe a variant of the translation initiation factor eIF3a, Rpg1-3, mutated in its PCI domain that displays an attenuated translation efficiency and formation of reversible assemblies at physiological growth conditions. Rpg1-3-GFP assemblies are not sequestered within mother cells only as usual for misfolded-protein aggregates and are freely transmitted from the mother cell into the bud although they are of non-amyloid nature. Their bud-directed transmission and the active movement within the cell area depend on the intact actin cytoskeleton and the related molecular motor Myo2. Mutations in the Rpg1-3 protein render not only eIF3a but, more importantly, also the eIF3 core complex prone to aggregation that is potentiated by the limited availability of Hsp70 and Hsp40 chaperones. Our results open the way to understand mechanisms yeast cells employ to cope with malfunction and aggregation of essential proteins and their complexes.
- Klíčová slova
- Actin, Aggregation, Asymmetric segregation, Hsp40, Hsp70, Myo2, Rpg1/eIF3a, Yeast,
- MeSH
- eukaryotický iniciační faktor 3 genetika MeSH
- lidé MeSH
- mikrofilamenta genetika MeSH
- mitochondrie MeSH
- mutace MeSH
- myosin typu V genetika MeSH
- proteinové agregáty genetika MeSH
- proteiny tepelného šoku HSP40 genetika MeSH
- proteiny tepelného šoku HSP70 genetika MeSH
- Saccharomyces cerevisiae - proteiny genetika MeSH
- Saccharomyces cerevisiae genetika růst a vývoj MeSH
- těžké řetězce myosinu genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- eukaryotický iniciační faktor 3 MeSH
- MYO2 protein, S cerevisiae MeSH Prohlížeč
- myosin typu V MeSH
- proteinové agregáty MeSH
- proteiny tepelného šoku HSP40 MeSH
- proteiny tepelného šoku HSP70 MeSH
- RPG1 protein, S cerevisiae MeSH Prohlížeč
- Saccharomyces cerevisiae - proteiny MeSH
- těžké řetězce myosinu MeSH
