Acetic acid inhibits nutrient uptake in Saccharomyces cerevisiae: auxotrophy confounds the use of yeast deletion libraries for strain improvement

As barley and oat production have recently increased in Canada, it has become prudent to investigate these cereal crops as potential feedstocks for alcoholic fermentation. Ethanol and other coproduct yields can vary substantially among fermented feedstocks, which currently consist primarily of wheat and corn. In this study, the liquified mash of milled grains from 28 barley (hulled and hull-less) and 12 oat cultivars were fermented with Saccharomyces cerevisiae to determine concentrations of fermentation products (ethanol, isopropanol, acetic acid, lactic acid, succinic acid, α-glycerylphosphorylcholine (α-GPC), and glycerol). On average, the fermentation of barley produced significantly higher amounts of ethanol, isopropanol, acetic acid, succinic acid, α-GPC, and glycerol than that of oats. The best performing barley cultivars were able to produce up to 78.48 g/L (CDC Clear) ethanol and 1.81 g/L α-GPC (CDC Cowboy). Furthermore, the presence of milled hulls did not impact ethanol yield amongst barley cultivars. Due to its superior ethanol yield compared to oats, barley is a suitable feedstock for ethanol production. In addition, the accumulation of α-GPC could add considerable value to the fermentation of these cereal crops.

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Translation machinery reprogramming in programmed cell death in Saccharomyces cerevisiae

Cell Death Discovery ◽

10.1038/s41420-020-00392-x ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Francesco Monticolo ◽

Emanuela Palomba ◽

Maria Luisa Chiusano

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Death ◽

Acetic Acid ◽

Programmed Cell Death ◽

Differential Expression ◽

Ribosomal Proteins ◽

Relative Proportion ◽

Duplication Event ◽

Genome Duplication Event ◽

Cell Death Pathway

AbstractProgrammed cell death involves complex molecular pathways in both eukaryotes and prokaryotes. In Escherichia coli, the toxin–antitoxin system (TA-system) has been described as a programmed cell death pathway in which mRNA and ribosome organizations are modified, favoring the production of specific death-related proteins, but also of a minor portion of survival proteins, determining the destiny of the cell population. In the eukaryote Saccharomyces cerevisiae, the ribosome was shown to change its stoichiometry in terms of ribosomal protein content during stress response, affecting the relative proportion between ohnologs, i.e., the couple of paralogs derived by a whole genome duplication event. Here, we confirm the differential expression of ribosomal proteins in yeast also during programmed cell death induced by acetic acid, and we highlight that also in this case pairs of ohnologs are involved. We also show that there are different trends in cytosolic and mitochondrial ribosomal proteins gene expression during the process. Moreover, we show that the exposure to acetic acid induces the differential expression of further genes coding for products related to translation processes and to rRNA post-transcriptional maturation, involving mRNA decapping, affecting translation accuracy, and snoRNA synthesis. Our results suggest that the reprogramming of the overall translation apparatus, including the cytosolic ribosome reorganization, are relevant events in yeast programmed cell death induced by acetic acid.

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Eukaryotic translation factor eIF5A contributes to acetic acid tolerance in Saccharomyces cerevisiae via transcriptional factor Ume6p

Biotechnology for Biofuels ◽

10.1186/s13068-021-01885-2 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Yanfei Cheng ◽

Hui Zhu ◽

Zhengda Du ◽

Xuena Guo ◽

Chenyao Zhou ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Acetic Acid ◽

Adaptive Response ◽

Acid Tolerance ◽

Peptide Bond ◽

Transcriptional Factor ◽

Yeast Cells ◽

Acetic Acid Tolerance ◽

Translation Factor ◽

Industrial Strains

Abstract Background Saccharomyces cerevisiae is well-known as an ideal model system for basic research and important industrial microorganism for biotechnological applications. Acetic acid is an important growth inhibitor that has deleterious effects on both the growth and fermentation performance of yeast cells. Comprehensive understanding of the mechanisms underlying S. cerevisiae adaptive response to acetic acid is always a focus and indispensable for development of robust industrial strains. eIF5A is a specific translation factor that is especially required for the formation of peptide bond between certain residues including proline regarded as poor substrates for slow peptide bond formation. Decrease of eIF5A activity resulted in temperature-sensitive phenotype of yeast, while up-regulation of eIF5A protected transgenic Arabidopsis against high temperature, oxidative or osmotic stress. However, the exact roles and functional mechanisms of eIF5A in stress response are as yet largely unknown. Results In this research, we compared cell growth between the eIF5A overexpressing and the control S. cerevisiae strains under various stressed conditions. Improvement of acetic acid tolerance by enhanced eIF5A activity was observed all in spot assay, growth profiles and survival assay. eIF5A prompts the synthesis of Ume6p, a pleiotropic transcriptional factor containing polyproline motifs, mainly in a translational related way. As a consequence, BEM4, BUD21 and IME4, the direct targets of Ume6p, were up-regulated in eIF5A overexpressing strain, especially under acetic acid stress. Overexpression of UME6 results in similar profiles of cell growth and target genes transcription to eIF5A overexpression, confirming the role of Ume6p and its association between eIF5A and acetic acid tolerance. Conclusion Translation factor eIF5A protects yeast cells against acetic acid challenge by the eIF5A-Ume6p-Bud21p/Ime4p/Bem4p axles, which provides new insights into the molecular mechanisms underlying the adaptive response and tolerance to acetic acid in S. cerevisiae and novel targets for construction of robust industrial strains.

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Publisher Correction: Strain Improvement of Native Saccharomyces cerevisiae LN ITCC 8246 Strain Through Protoplast Fusion to Enhance Its Xylose Uptake

Applied Biochemistry and Biotechnology ◽

10.1007/s12010-021-03575-z ◽

2021 ◽

Author(s):

Shalley Sharma ◽

Chandrika Ghoshal ◽

Anju Arora ◽

Wara Samar ◽

Lata Nain ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Protoplast Fusion ◽

Strain Improvement ◽

Xylose Uptake

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Cytochrome c Trp65Ser substitution results in inhibition of acetic acid-induced programmed cell death in Saccharomyces cerevisiae

Mitochondrion ◽

10.1016/j.mito.2011.08.007 ◽

2011 ◽

Vol 11 (6) ◽

pp. 987-991 ◽

Cited By ~ 5

Author(s):

Nicoletta Guaragnella ◽

Salvatore Passarella ◽

Ersilia Marra ◽

Sergio Giannattasio

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Death ◽

Acetic Acid ◽

Cytochrome C ◽

Programmed Cell Death

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Functional Genomics Using the Saccharomyces cerevisiae Yeast Deletion Collections

Cold Spring Harbor Protocols ◽

10.1101/pdb.top080945 ◽

2016 ◽

Vol 2016 (9) ◽

pp. pdb.top080945

Author(s):

Corey Nislow ◽

Lai Hong Wong ◽

Amy Huei-Yi Lee ◽

Guri Giaever

Keyword(s):

Saccharomyces Cerevisiae ◽

Functional Genomics ◽

Yeast Deletion

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Endogenous lycopene improves ethanol production under acetic acid stress in Saccharomyces cerevisiae

Biotechnology for Biofuels ◽

10.1186/s13068-018-1107-y ◽

2018 ◽

Vol 11 (1) ◽

Cited By ~ 7

Author(s):

Shuo Pan ◽

Bin Jia ◽

Hong Liu ◽

Zhen Wang ◽

Meng-Zhe Chai ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Acetic Acid ◽

Ethanol Production ◽

Acid Stress

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Evolutionary and reverse engineering to increase Saccharomyces cerevisiae tolerance to acetic acid, acidic pH, and high temperature

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11730-z ◽

2021 ◽

Author(s):

Prisciluis Caheri Salas-Navarrete ◽

Arturo Iván Montes de Oca Miranda ◽

Alfredo Martínez ◽

Luis Caspeta

Keyword(s):

Saccharomyces Cerevisiae ◽

Acetic Acid ◽

High Temperature ◽

Reverse Engineering ◽

Acidic Ph

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Selection of Saccharomyces cerevisiae Starter Strain for Merwah Wine

Fermentation ◽

10.3390/fermentation6020043 ◽

2020 ◽

Vol 6 (2) ◽

pp. 43

Author(s):

Nadine Feghali ◽

Angela Bianco ◽

Giacomo Zara ◽

Edouard Tabet ◽

Chantal Ghanem ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Acetic Acid ◽

Pilot Scale ◽

Molecular Monitoring ◽

Technological Parameters ◽

Sensorial Analysis ◽

Spontaneous Fermentation ◽

Wine Production ◽

Wild Yeasts ◽

Selection Of

In order to select Saccharomyces cerevisiae starter strains for ‘‘Merwah’’ wine production, three strains (M.6.16, M.10.16, and M.4.17) previously isolated from ‘‘Merwah’’ must and characterized at the lab scale were tested in pilot-scale fermentation in a Lebanese winery during the 2019 vintage. The three inoculated musts were compared to that obtained with a spontaneous fermentation. During the fermentations, must samples were taken to evaluate the dominance of the inoculated strains, and at the end of fermentation, the obtained wines were subjected to chemical and sensorial characterization. Molecular monitoring by interdelta analysis revealed that only M.4.17 was able to complete the fermentation and dominate over the wild yeasts. Based on the analysis of principal technological parameters (i.e., residual sugar, fermentative vigor, sulfur production, and acetic acid) and sensorial analysis of the wines obtained, M.4.17 was selected as an adequate starter for the production of typical ‘‘Merwah’’ wine.

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