Relief from nitrogen starvation entails quick unexpected down-regulation of glycolytic/lipid metabolism genes in enologicalSaccharomyces cerevisiae

AbstractNitrogen composition of the grape must has an impact on yeast growth and fermentation kinetics as well as on the organoleptic properties of the final product. In some technological processes, such as white wine/rosé winemaking, the yeast-assimilable nitrogen content is sometimes insufficient to cover yeast requirements, which can lead to slow or sluggish fermentations. Growth is nevertheless quickly restored upon relief from nutrient starvation, e.g. through the addition of ammonium nitrogen, allowing fermentation completion. The aim of this study was to determine how nitrogen repletion affected the transcriptional response of aSaccharomyces cerevisiaewine yeast strain, in particular within the first hour after nitrogen addition. We found almost 4800 genes induced or repressed, sometimes within minutes after nutrient changes. Some of these responses to nitrogen depended on the TOR pathway, which controls positively ribosomal protein genes, amino acid and purine biosynthesis or amino acid permease genes and negatively stress-response genes, and genes related to the retrograde response (RTG) specific to the tricarboxylic acid (TCA) cycle and nitrogen catabolite repression (NCR). Some unexpected transcriptional responses concerned all the glycolytic genes, carbohydrate metabolism and TCA cycle-related genes that were down-regulated, as well as genes from the lipid metabolism.

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Regulation of the TCA cycle and the general amino acid permease by overflow metabolism in Rhizobium leguminosarum

Microbiology ◽

10.1099/00221287-143-7-2209 ◽

1997 ◽

Vol 143 (7) ◽

pp. 2209-2221 ◽

Cited By ~ 55

Author(s):

D. L. Walshaw ◽

A. Wilkinson ◽

M. Mundy ◽

M. Smith ◽

P. S. Poole

Keyword(s):

Amino Acid ◽

Rhizobium Leguminosarum ◽

Tca Cycle ◽

Overflow Metabolism ◽

Amino Acid Permease ◽

The Tca Cycle ◽

General Amino Acid Permease

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Saccharomyces cerevisiae Cytosolic Thioredoxins Control Glycolysis, Lipid Metabolism, and Protein Biosynthesis under Wine-Making Conditions

Applied and Environmental Microbiology ◽

10.1128/aem.02953-18 ◽

2019 ◽

Vol 85 (7) ◽

Cited By ~ 2

Author(s):

Cecilia Picazo ◽

Brian McDonagh ◽

José Peinado ◽

José A. Bárcena ◽

Emilia Matallana ◽

...

Keyword(s):

Oxidative Stress ◽

Saccharomyces Cerevisiae ◽

Lipid Metabolism ◽

Amino Acid ◽

Oxidative Damage ◽

Mutant Strain ◽

Grape Juice ◽

Wine Yeast ◽

Content Type ◽

Small Proteins

ABSTRACT Thioredoxins are small proteins that regulate the cellular redox state, prevent oxidative damage, and play an active role in cell repair. Oxidative stress has proven to be of much relevance in biotechnological processes when the metabolism of Saccharomyces cerevisiae is mainly respiratory. During wine yeast starter production, active dry yeast cytosolic thioredoxin Trx2p is a key player in protecting metabolic enzymes from being oxidized by carbonylation. Less is known about the role of redox control during grape juice fermentation. A mutant strain that lacked both cytosolic thioredoxins, Trx1p and Trx2p, was tested for grape juice fermentation. Its growth and sugar consumption were greatly impaired, which indicates the system’s relevance under fermentative conditions. A proteomic analysis indicated that deletion of the genes TRX1 and TRX2 caused a reduction in the ribosomal proteins and factors involved in translation elongation in addition to enzymes for glycolysis and amino acid biosynthesis. A metabolomic analysis of the trx1Δ trx2Δ mutant showed an increase in most proteogenic amino acids, phospholipids, and sphingolipids and higher fatty acid desaturase Ole1p content. Low glycolytic activity was behind the reduced growth and fermentative capacity of the thioredoxin deletion strain. All three hexokinases were downregulated in the mutant strain, but total hexokinase activity remained, probably due to posttranslational regulation. Pyruvate kinase Cdc19p presented an early level of aggregation in the trx1Δ trx2Δ mutant, which may contribute to a diminished hexose metabolism and trigger regulatory mechanisms that could influence the level of glycolytic enzymes. IMPORTANCE Oxidative stress is a common hazardous condition that cells have to face in their lifetime. Oxidative damage may diminish cell vitality and viability by reducing metabolism and eventually leading to aging and ultimate death. Wine yeast Saccharomyces cerevisiae also faces oxidative attack during its biotechnological uses. One of the main yeast antioxidant systems involves two small proteins called thioredoxins. When these two proteins are removed, wine yeast shows diminished growth, protein synthesis, and sugar metabolism under wine-making conditions, and amino acid and lipid metabolism are also affected. Altogether, our results indicate that proper redox regulation is a key factor for metabolic adaptations during grape juice fermentation.

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Genome-wide identification of the amino acid permease genes and molecular characterization of their transcriptional responses to various nutrient stresses in allotetraploid rapeseed

BMC Plant Biology ◽

10.1186/s12870-020-02367-7 ◽

2020 ◽

Vol 20 (1) ◽

Cited By ~ 1

Author(s):

Ting Zhou ◽

Cai-peng Yue ◽

Jin-yong Huang ◽

Jia-qian Cui ◽

Ying Liu ◽

...

Keyword(s):

Amino Acid ◽

Molecular Characterization ◽

Amino Acid Permease ◽

Transcriptional Responses ◽

Genome Wide

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Faculty Opinions recommendation of A conserved GTPase-containing complex is required for intracellular sorting of the general amino-acid permease in yeast.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1040377.489550 ◽

2006 ◽

Author(s):

Ruth Collins

Keyword(s):

Amino Acid ◽

Amino Acid Permease ◽

General Amino Acid Permease ◽

Intracellular Sorting

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Effect of Huangqin Tang on Urine Metabolic Profile in Rats with Ulcerative Colitis Based on UPLC-Q-Exactive Orbitrap MS

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2020/1874065 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Dunfang Wang ◽

Xuran Ma ◽

Shanshan Guo ◽

Yanli Wang ◽

Tao Li ◽

...

Keyword(s):

Ulcerative Colitis ◽

Fatty Acids ◽

Amino Acid ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Unsaturated Fatty Acids ◽

Tricarboxylic Acid Cycle ◽

Tca Cycle ◽

Q Exactive ◽

Therapeutic Mechanisms

As a classic prescription, Huangqin Tang (HQT) has been widely applied to treat ulcerative colitis (UC), although its pharmacological mechanisms are not clear. In this study, urine metabolomics was first analysed to explore the therapeutic mechanisms of HQT in UC rats induced by TNBS. We identified 28 potential biomarkers affected by HQT that might cause changes in urine metabolism in UC rats, mapped the network of metabolic pathways, and revealed how HQT affects metabolism of UC rats. The results showed that UC affects amino acid metabolism and biosynthesis of unsaturated fatty acids and impairs the tricarboxylic acid cycle (TCA cycle). UC induced inflammatory and gastrointestinal reactions by inhibiting the transport of fatty acids and disrupting amino acid metabolism. HQT plays key roles via regulating the level of biomarkers in the metabolism of amino acids, lipids, and so on, normalizing metabolic disorders. In addition, histopathology and other bioinformatics analysis further confirm that HQT altered UC rat physiology and pathology, ultimately affecting metabolic function of UC rats.

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Itaconate Alters Succinate and Coenzyme A Metabolism via Inhibition of Mitochondrial Complex II and Methylmalonyl-CoA Mutase

Metabolites ◽

10.3390/metabo11020117 ◽

2021 ◽

Vol 11 (2) ◽

pp. 117

Author(s):

Thekla Cordes ◽

Christian M. Metallo

Keyword(s):

Amino Acid ◽

Metabolic Pathways ◽

Mammalian Cells ◽

Coenzyme A ◽

Cultured Cells ◽

Tca Cycle ◽

Regulatory Function ◽

Reversible Inhibitor ◽

Complex Ii ◽

Branched Chain

Itaconate is a small molecule metabolite that is endogenously produced by cis-aconitate decarboxylase-1 (ACOD1) in mammalian cells and influences numerous cellular processes. The metabolic consequences of itaconate in cells are diverse and contribute to its regulatory function. Here, we have applied isotope tracing and mass spectrometry approaches to explore how itaconate impacts various metabolic pathways in cultured cells. Itaconate is a competitive and reversible inhibitor of Complex II/succinate dehydrogenase (SDH) that alters tricarboxylic acid (TCA) cycle metabolism leading to succinate accumulation. Upon activation with coenzyme A (CoA), itaconyl-CoA inhibits adenosylcobalamin-mediated methylmalonyl-CoA (MUT) activity and, thus, indirectly impacts branched-chain amino acid (BCAA) metabolism and fatty acid diversity. Itaconate, therefore, alters the balance of CoA species in mitochondria through its impacts on TCA, amino acid, vitamin B12, and CoA metabolism. Our results highlight the diverse metabolic pathways regulated by itaconate and provide a roadmap to link these metabolites to potential downstream biological functions.

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