Evaluating the genetic basis of anti-cancer property of Taxol in Saccharomyces cerevisiae model
Taxol has been regarded as one of the most successful anti-cancer drugs identified from natural sources to date. Although taxol is known to sensitize cells by stabilizing microtubules, its ability to cause DNA damage in peripheral blood lymphocytes, and to induce oxidative stress and apoptosis indicates that taxol may have other modes of cytotoxic action. This study focuses on identifying the additional targets of taxol that may contribute to its multifaceted cell killing property, using Saccharomyces cerevisiae.
We show that yeast oxidative stress response mutants (sod1Δ, tsa1Δ and cta1Δ) and DNA damage response mutants (mre11∆, sgs1∆ and sub1∆) are highly sensitive to Taxol. Our results also show that taxol increases the level of reactive oxygen species (ROS) in yeast oxidative stress response mutant strains. Further, 4′,6-Diamidino-2′-phenylindole (DAPI) and acridine orange/ethidium bromide (AO/EB) staining show that taxol induces apoptotic features such as nuclear fragmentation and chromatin condensation in DNA repair mutants. On the whole, our results suggest that taxol’s cytotoxic property is attributed to its multifaceted mechanism of action.
Saccharomyces cerevisiae Synthetic Transcriptional Networks Harnessing dCas12a and Type V-A anti-CRISPR Proteins.
Type V-A anti-CRISPR proteins (AcrVAs) represent the response from phages to the CRISPR-Cas12a prokaryotic immune system. CRISPR-Cas12a was repurposed, in high eukaryotes, to carry out gene editing and transcription regulation, the latter via a nuclease-dead Cas12a (dCas12a). Consequently, AcrVAs were adopted to regulate (d)Cas12a activity. However, the usage of both dCas12a-based transcription factors and AcrVAs in the yeast Saccharomyces cerevisiae has not been explored. In this work, we show that, in the baker’s yeast, two dCas12a proteins (denAsCas12a and dLbCas12a) work both as activators (upon fusion to a strong activation domain) and repressors, whereas dMbCa12a is nonfunctional.
The activation efficiency of dCas12a-ADs manifests a dependence on the number of crRNA binding sites, whereas it is not directly correlated to the amount of crRNA in the cells. Moreover, AcrVA1, AcrVA4, and AcrVA5 are able to inhibit dLbCa12a in yeast, and denAsCas12a is only inhibited by AcrVA1. However, AcrVA1 performs well at high concentration only. Coexpression of two or three AcrVAs does not enhance inhibition of dCas12a(-AD), suggesting a competition between different AcrVAs. Further, AcrVA4 significantly limits gene editing by LbCas12a. Overall, our results indicate that dCas12a:crRNA and AcrVA proteins are highly performant components in S. cerevisiae synthetic transcriptional networks.
Influence of technological procedures on viability, probiotic and anti-mycotoxin properties of Saccharomyces boulardii RC009, and biological safety studies
The objective was to evaluate the technological processing (protection strategies and storage conditions) influence on viability, on probiotic properties and adsorbent aflatoxin B1 capacity of S. boulardii RC009. Also, the yeast biological safety was evaluated. Lyophilisation (DL) and encapsulation + lyophilisation (EL) were conducted. Yeast protected with maltodextrin (M) or WPC stored at 4 °C reduced 1 and 2 log the viability, respectively. Yeast protected with M stored at 25 °C reduced 1 log after 70 d; with WPC the viability significantly reduced 3 log after 30 d. Technological processing improved the coaggregation’s capacity with pathogens and DL process allowed the greatest AFB1 adsorption. S. boulardii 106 cells/mL were no toxic to Vero cells (p˂0.05). Saccharomyces boulardii RC009 protected with M or WPC maintained viability after technological processing. It possesses a great capacity for AFB1 adsorption and probiotic properties and could be considered a candidate with proven safety for functional food products development.
Proteasome control of [URE3] prion propagation by degradation of anti-prion proteins Cur1 and Btn2 in Saccharomyces cerevisiae
[URE3] is a prion of the nitrogen catabolism controller, Ure2p, and [PSI+] is a prion of the translation termination factor Sup35p in S. cerevisiae. Btn2p cures [URE3] by sequestration of Ure2p amyloid filaments. Cur1p, paralogous to Btn2p, also cures [URE3], but by a different (unknown) mechanism. We find that an array of mutations impairing proteasome assembly or MG132 inhibition of proteasome activity result in loss of [URE3]. In proportion to their prion-curing effects, each mutation affecting proteasomes elevates the cellular concentration of the antiprion proteins Btn2 and Cur1. Of > 4600 proteins detected by SILAC, Btn2p was easily the most overexpressed in a pre9Δ (α3 core subunit) strain. Indeed, deletion of BTN2 and CUR1 prevents the prion-curing effects of proteasome impairment.
Surprisingly, the 15 most unstable yeast proteins are not increased in pre9Δ cells suggesting altered proteasome specificity rather than simple inactivation. Hsp42, a chaperone that cooperates with Btn2 and Cur1 in curing [URE3], is also necessary for the curing produced by proteasome defects, although Hsp42p levels are not substantially altered by a proteasome defect. We find that pre9Δ and proteasome chaperone mutants that most efficiently lose [URE3], do not destabilize [PSI+] or alter cellular levels of Sup35p. A tof2 mutation or deletion likewise destabilizes [URE3], and elevates Btn2p, suggesting that Tof2p deficiency inactivates proteasomes. We suggest that when proteasomes are saturated with denatured/misfolded proteins, their reduced degradation of Btn2p and Cur1p automatically upregulates these aggregate-handling systems to assist in the clean-up.
A novel aqueous extract from rice fermented with Aspergillus oryzae and Saccharomyces cerevisiae possesses an anti-influenza A virus activity
Human influenza virus infections occur annually worldwide and are associated with high morbidity and mortality. Hence, development of novel anti-influenza drugs is urgently required. Rice Power extract developed by the Yushin Brewer Co. Ltd. is a novel aqueous extract of rice obtained via saccharization and fermentation with various microorganisms, such as Aspergillus oryzae, yeast [such as Saccharomyces cerevisiae], and lactic acid bacteria, possessing various biological and pharmacological properties. In our previous experimental screening with thirty types of Rice Power extracts, we observed that the 30th Rice Power (Y30) extract promoted the survival of influenza A virus-infected Madin-Darby canine kidney (MDCK) cells. Therefore, to identify compounds for the development of novel anti-influenza drugs, we aimed to investigate whether the Y30 extract exhibits anti-influenza A virus activity. In the present study, we demonstrated that the Y30 extract strongly promoted the survival of influenza A H1N1 Puerto Rico 8/34 (A/PR/8/34), California 7/09, or H3N2 Aichi 2/68 (A/Aichi/2/68) viruses-infected MDCK cells and inhibited A/PR/8/34 or A/Aichi/2/68 viruses infection and growth in the co-treatment and pre-infection experiments.
Saccharomyces cerevisiae (S. cerevisiae) Antibody |
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| abx411590-1ml | Abbexa | 1 ml | 610.8 EUR |
Human Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E01A0876-192T | BlueGene | 192 tests | 1524 EUR |
Human Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E01A0876-48 | BlueGene | 1 plate of 48 wells | 624 EUR |
Human Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E01A0876-96 | BlueGene | 1 plate of 96 wells | 822 EUR |
Dog Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E08A0876-192T | BlueGene | 192 tests | 1524 EUR |
Dog Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E08A0876-48 | BlueGene | 1 plate of 48 wells | 624 EUR |
Dog Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E08A0876-96 | BlueGene | 1 plate of 96 wells | 822 EUR |
Pig Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E07A0876-192T | BlueGene | 192 tests | 1524 EUR |
Pig Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E07A0876-48 | BlueGene | 1 plate of 48 wells | 624 EUR |
Pig Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E07A0876-96 | BlueGene | 1 plate of 96 wells | 822 EUR |
Rat Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E02A0876-192T | BlueGene | 192 tests | 1524 EUR |
Rat Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E02A0876-48 | BlueGene | 1 plate of 48 wells | 624 EUR |
Rat Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E02A0876-96 | BlueGene | 1 plate of 96 wells | 822 EUR |
Goat Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E06A0876-192T | BlueGene | 192 tests | 1524 EUR |
Goat Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E06A0876-48 | BlueGene | 1 plate of 48 wells | 624 EUR |
Goat Anti Saccharomyces cerevisiae antibody ELISA kit |
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| E06A0876-96 | BlueGene | 1 plate of 96 wells | 822 EUR |
The pre-treatment of Y30 extract on MDCK cells did not induce anti-influenza activity in the cell. The Y30 extract did not significantly affect influenza A virus hemagglutination, and neuraminidase and RNA-dependent RNA polymerase activities. Interestingly, the electron microscopy experiment revealed that the Y30 extract disrupts the integrity of influenza A virus particles by permeabilizing the viral membrane envelope, suggesting that Y30 extract has a direct virucidal effect against influenza A virus. Furthermore, we observed that compared to the ethyl acetate (EtOAc) extract, the water extract of Y30 extract considerably promoted the survival of cells infected with A/PR/8/34 virus. These results indicated that more anti-influenza components were present in the water extract of Y30 extract than in the EtOAc extract. Our results highlight the potential of a rice extract fermented with A. oryzae and S. cerevisiae as an anti-influenza medicine and a drug source for the development of anti-influenza compounds.