scholarly journals Transcriptional Response of Saccharomyces cerevisiae to the Plasma Membrane-Perturbing Compound Chitosan

2005 ◽  
Vol 4 (4) ◽  
pp. 703-715 ◽  
Author(s):  
Anna Zakrzewska ◽  
Andre Boorsma ◽  
Stanley Brul ◽  
Klaas J. Hellingwerf ◽  
Frans M. Klis
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Wall ◽  
Transcription Factor ◽  
Plasma Membrane ◽  
Transcriptional Response ◽  
Wall Stress ◽  
Yeast Cells ◽  
Transcriptional Responses ◽  
Cell Wall Stress ◽  
Spoilage Yeast

ABSTRACT Chitosan is a plasma membrane-perturbing compound consisting of linear chains of β-1,4-linked glucosamine residues, which at acidic pHs become positively charged. It is extensively used as an antimicrobial compound, yet its mode of action is still unresolved. Chitosan strongly affected the growth of the yeast Saccharomyces cerevisiae, the food spoilage yeast Zygosaccharomyces bailii, and two human-pathogenic yeasts, Candida albicans and Candida glabrata. Microarray analysis of yeast cells treated with sublethal concentrations of chitosan revealed induction of the environmental stress response and three more major transcriptional responses. The first was a rapid and stable Cin5p-mediated response. Cin5p/Yap4p is a transcription factor involved in various stress responses. Deletion of CIN5 led to increased chitosan sensitivity. The second was a Crz1p-mediated response, which is delayed compared to the Cin5p response. Crz1p is a transcription factor of the calcineurin pathway. Cells deleted for CRZ1 or treated with the calcineurin inhibitor FK506 became hypersensitive to chitosan, supporting the notion that the Crz1p-controlled response offers protection against chitosan. The third was a strong Rlm1p-mediated response which ran parallel in time with the Crz1p-regulated response. Rlm1p is a transcription factor of the cell wall integrity pathway, which is activated by cell wall stress. Importantly, chitosan-treated cells became more resistant to β-1,3-glucanase, which is a well-known response to cell wall stress. We propose that the transcriptional response to chitosan may be representative of other plasma membrane-perturbing compounds.

scholarly journals Efg1 and Cas5 Orchestrate Cell Wall Damage Response to Caspofungin in Candida albicans

2020 ◽  
Author(s):  
Kang Xiong ◽  
Chang Su ◽  
Qiangqiang Sun ◽  
Yang Lu
Keyword(s):  
Cell Wall ◽  
Transcription Factor ◽  
Candida Albicans ◽  
Transcriptional Response ◽  
Wall Stress ◽  
Growth Defect ◽  
Transcriptional Responses ◽  
Cell Wall Stress ◽  
Cell Wall Damage

Echinocandins are recommended as the first-line drugs for the treatment of systemic candidiasis. Cas5 is a key transcription factor involved in the response to cell wall damage induced by echinocandins. Here, through a genetic screen, we report the identification of a second transcription factor Efg1 that is also crucial for proper transcriptional responses to echinocandins. Like CAS5, deletion of EFG1 confers hypersensitivity to caspofungin. Efg1 is required for the induction of CAS5 in response to caspofungin. However, ectopically expressed CAS5 cannot rescue the growth defect of efg1 mutant in caspofungin-containing medium. Deleting EFG1 in the cas5 mutant exacerbates the cell wall stress upon caspofungin addition and renders caspofungin-resistant Candida albicans responsive to treatment. Genome-wide transcription profiling of efg1/efg1 and cas5/cas5 using a RNA-Seq indicates that Efg1 and Cas5 co-regulate numbers of caspofungin-responsive genes expression, but they also independently control some genes induction. We further show that Efg1 interacts with Cas5 by yeast two-hybrid and in vivo immunoprecipitation in the presence or absence of caspofungin. Importantly, Efg1 and Cas5 bind to some caspofungin-responsive genes promoter to coordinately activate their expression. Thus, we demonstrate that Efg1, together with Cas5, controls the transcriptional response to cell wall stress induced by caspofungin.

scholarly journals Physiological and Transcriptional Responses of Saccharomyces cerevisiae tod-Limonene Show Changes to the Cell Wall but Not to the Plasma Membrane

2013 ◽  
Vol 79 (12) ◽  
pp. 3590-3600 ◽  
Author(s):  
Timothy C. R. Brennan ◽  
Jens O. Krömer ◽  
Lars K. Nielsen
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Wall ◽  
Plasma Membrane ◽  
Fatty Acid ◽  
Structural Integrity ◽  
Fatty Acid Biosynthesis ◽  
Membrane Integrity ◽  
Ethanol Exposure ◽  
Yeast Cells ◽  
Transcriptional Responses

ABSTRACTMonoterpenes can, upon hydrogenation, be used as light-fraction components of sustainable aviation fuels. Fermentative production of monoterpenes in engineered microorganisms, such asSaccharomyces cerevisiae, has gained attention as a potential route to deliver these next-generation fuels from renewable biomass. However, end product toxicity presents a formidable problem for microbial synthesis. Due to their hydrophobicity, monoterpene inhibition has long been attributed to membrane interference, but the molecular mechanism remains largely unsolved. In order to gain a better understanding of the mode of action, we analyzed the composition and structural integrity of the cell envelope as well as the transcriptional response of yeast cells treated with an inhibitory amount ofd-limonene (107 mg/liter). We found no alterations in membrane fluidity, structural membrane integrity, or fatty acid composition after the solvent challenge. A 4-fold increase in the mean fluorescence intensity per cell (using calcofluor white stain) and increased sensitivity to cell wall-degrading enzymes demonstrated that limonene disrupts cell wall properties. Global transcript measurements confirmed the membrane integrity observations by showing no upregulation of ergosterol or fatty acid biosynthesis pathways, which are commonly overexpressed in yeast to reinforce membrane rigidity during ethanol exposure. Limonene shock did cause a compensatory response to cell wall damage through overexpression of several genes (ROM1,RLM1,PIR3,CTT1,YGP1,MLP1,PST1, andCWP1) involved with the cell wall integrity signaling pathway. This is the first report demonstrating that cell wall, rather than plasma membrane, deterioration is the main source of monoterpene inhibition. We show that limonene can alter the structure and function of the cell wall, which has a clear effect on cytokinesis.

scholarly journals Chitin Synthesis in Saccharomyces cerevisiae in Response to Supplementation of Growth Medium with Glucosamine and Cell Wall Stress

2003 ◽  
Vol 2 (5) ◽  
pp. 886-900 ◽  
Author(s):  
Dorota A. Bulik ◽  
Mariusz Olczak ◽  
Hector A. Lucero ◽  
Barbara C. Osmond ◽  
Phillips W. Robbins ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Wall ◽  
Plasma Membrane ◽  
Growth Medium ◽  
Specific Activity ◽  
Neck Region ◽  
Wall Stress ◽  
Chitin Synthesis ◽  
Fourfold Increase ◽  
Cell Wall Stress

ABSTRACT In Saccharomyces cerevisiae most chitin is synthesized by Chs3p, which deposits chitin in the lateral cell wall and in the bud-neck region during cell division. We have recently found that addition of glucosamine (GlcN) to the growth medium leads to a three- to fourfold increase in cell wall chitin levels. We compared this result to the increases in cellular chitin levels associated with cell wall stress and with treatment of yeast with mating pheromone. Since all three phenomena lead to increases in precursors of chitin, we hypothesized that chitin synthesis is at least in part directly regulated by the size of this pool. This hypothesis was strengthened by our finding that addition of GlcN to the growth medium causes a rapid increase in chitin synthesis without any pronounced change in the expression of more than 6,000 genes monitored with Affymetrix gene expression chips. In other studies we found that the specific activity of Chs3p is higher in the total membrane fractions from cells grown in GlcN and from mutants with weakened cell walls. Sucrose gradient analysis shows that Chs3p is present in an inactive form in what may be Golgi compartments but as an active enzyme in other intracellular membrane-bound vesicles, as well as in the plasma membrane. We conclude that Chs3p-dependent chitin synthesis in S. cerevisiae is regulated both by the levels of intermediates of the UDP-GlcNAc biosynthetic pathway and by an increase in the activity of the enzyme in the plasma membrane.

scholarly journals The Aspergillus niger MADS-box transcription factor RlmA is required for cell wall reinforcement in response to cell wall stress

2005 ◽  
Vol 58 (1) ◽  
pp. 305-319 ◽  
Author(s):  
Robbert A. Damveld ◽  
Mark Arentshorst ◽  
Angelique Franken ◽  
Patricia A. VanKuyk ◽  
Frans M. Klis ◽  
...  
Keyword(s):  
Cell Wall ◽  
Transcription Factor ◽  
Aspergillus Niger ◽  
Wall Stress ◽  
Mads Box ◽  
Cell Wall Stress ◽  
Cell Wall Reinforcement

scholarly journals The Transcription Factor SomA Synchronously Regulates Biofilm Formation and Cell Wall Homeostasis in Aspergillus fumigatus

mBio ◽  
2020 ◽  
Vol 11 (6) ◽  
Author(s):  
Yuan Chen ◽  
Francois Le Mauff ◽  
Yan Wang ◽  
Ruiyang Lu ◽  
Donald C. Sheppard ◽  
...  
Keyword(s):  
Cell Wall ◽  
Transcription Factor ◽  
Aspergillus Fumigatus ◽  
Biofilm Formation ◽  
Wall Stress ◽  
Fungal Cell ◽  
Glucan Synthase ◽  
Content Type ◽  
Cell Wall Stress ◽  
Chitin Synthases

ABSTRACT Polysaccharides are key components of both the fungal cell wall and biofilm matrix. Despite having distinct assembly and regulation pathways, matrix exopolysaccharide and cell wall polysaccharides share common substrates and intermediates in their biosynthetic pathways. It is not clear, however, if the biosynthetic pathways governing the production of these polysaccharides are cooperatively regulated. Here, we demonstrate that cell wall stress promotes production of the exopolysaccharide galactosaminogalactan (GAG)-depend biofilm formation in the major fungal pathogen of humans Aspergillus fumigatus and that the transcription factor SomA plays a crucial role in mediating this process. A core set of SomA target genes were identified by transcriptome sequencing and chromatin immunoprecipitation coupled to sequencing (ChIP-Seq). We identified a novel SomA-binding site in the promoter regions of GAG biosynthetic genes agd3 and ega3, as well as its regulators medA and stuA. Strikingly, this SomA-binding site was also found in the upstream regions of genes encoding the cell wall stress sensors, chitin synthases, and β-1,3-glucan synthase. Thus, SomA plays a direct regulation of both GAG and cell wall polysaccharide biosynthesis. Consistent with these findings, SomA is required for the maintenance of normal cell wall architecture and compositions in addition to its function in biofilm development. Moreover, SomA was found to globally regulate glucose uptake and utilization, as well as amino sugar and nucleotide sugar metabolism, which provides precursors for polysaccharide synthesis. Collectively, our work provides insight into fungal adaptive mechanisms in response to cell wall stress where biofilm formation and cell wall homeostasis were synchronously regulated. IMPORTANCE The cell wall is essential for fungal viability and is absent from human hosts; thus, drugs disrupting cell wall biosynthesis have gained more attention. Caspofungin is a member of a new class of clinically approved echinocandin drugs to treat invasive aspergillosis by blocking β-1,3-glucan synthase, thus damaging the fungal cell wall. Here, we demonstrate that caspofungin and other cell wall stressors can induce galactosaminogalactan (GAG)-dependent biofilm formation in the human pathogen Aspergillus fumigatus. We further identified SomA as a master transcription factor playing a dual role in both biofilm formation and cell wall homeostasis. SomA plays this dual role by direct binding to a conserved motif upstream of GAG biosynthetic genes and genes involved in cell wall stress sensors, chitin synthases, and β-1,3-glucan synthase. Collectively, these findings reveal a transcriptional control pathway that integrates biofilm formation and cell wall homeostasis and suggest SomA as an attractive target for antifungal drug development.

scholarly journals The Sequential Activation of the Yeast HOG and SLT2 Pathways Is Required for Cell Survival to Cell Wall Stress

2008 ◽  
Vol 19 (3) ◽  
pp. 1113-1124 ◽  
Author(s):  
Clara Bermejo ◽  
Estefanía Rodríguez ◽  
Raúl García ◽  
Jose M. Rodríguez-Peña ◽  
María L. Rodríguez de la Concepción ◽  
...  
Keyword(s):  
Cell Wall ◽  
Cell Survival ◽  
Wall Stress ◽  
Hog Pathway ◽  
Transcriptional Responses ◽  
Cell Wall Stress ◽  
Cell Wall Damage ◽  
Mapk Pathways ◽  
Essential Components ◽  
Sequential Activation

Yeast mitogen-activated protein kinase (MAPK) signaling pathways transduce external stimuli into cellular responses very precisely. The MAPKs Slt2/Mpk1 and Hog1 regulate transcriptional responses of adaptation to cell wall and osmotic stresses, respectively. Unexpectedly, we observe that the activation of a cell wall integrity (CWI) response to the cell wall damage caused by zymolyase (β-1,3 glucanase) requires both the HOG and SLT2 pathways. Zymolyase activates both MAPKs and Slt2 activation depends on the Sho1 branch of the HOG pathway under these conditions. Moreover, adaptation to zymolyase requires essential components of the CWI pathway, namely the redundant MAPKKs Mkk1/Mkk2, the MAPKKK Bck1, and Pkc1, but it does not require upstream elements, including the sensors and the guanine nucleotide exchange factors of this pathway. In addition, the transcriptional activation of genes involved in adaptation to cell wall stress, like CRH1, depends on the transcriptional factor Rlm1 regulated by Slt2, but not on the transcription factors regulated by Hog1. Consistent with these findings, both MAPK pathways are essential for cell survival under these circumstances because mutant strains deficient in different components of both pathways are hypersensitive to zymolyase. Thus, a sequential activation of two MAPK pathways is required for cellular adaptation to cell wall damage.

scholarly journals Vacuolar H+-ATPase Protects Saccharomyces cerevisiae Cells against Ethanol-Induced Oxidative and Cell Wall Stresses

2016 ◽  
Vol 82 (10) ◽  
pp. 3121-3130 ◽  
Author(s):  
Sirikarn Charoenbhakdi ◽  
Thanittra Dokpikul ◽  
Thanawat Burphan ◽  
Todsapol Techo ◽  
Choowong Auesukaree
Keyword(s):  
Cell Wall ◽  
Alcoholic Fermentation ◽  
Ethanol Tolerance ◽  
Wall Stress ◽  
Yeast Cells ◽  
Intracellular Acidification ◽  
Straight Chain ◽  
Cell Wall Stress ◽  
Yeast Strains ◽  
Vacuolar Acidification

ABSTRACTDuring fermentation, increased ethanol concentration is a major stress for yeast cells. Vacuolar H+-ATPase (V-ATPase), which plays an important role in the maintenance of intracellular pH homeostasis through vacuolar acidification, has been shown to be required for tolerance to straight-chain alcohols, including ethanol. Since ethanol is known to increase membrane permeability to protons, which then promotes intracellular acidification, it is possible that the V-ATPase is required for recovery from alcohol-induced intracellular acidification. In this study, we show that the effects of straight-chain alcohols on membrane permeabilization and acidification of the cytosol and vacuole are strongly dependent on their lipophilicity. These findings suggest that the membrane-permeabilizing effect of straight-chain alcohols induces cytosolic and vacuolar acidification in a lipophilicity-dependent manner. Surprisingly, after ethanol challenge, the cytosolic pH in Δvma2and Δvma3mutants lacking V-ATPase activity was similar to that of the wild-type strain. It is therefore unlikely that the ethanol-sensitive phenotype ofvmamutants resulted from severe cytosolic acidification. Interestingly, thevmamutants exposed to ethanol exhibited a delay in cell wall remodeling and a significant increase in intracellular reactive oxygen species (ROS). These findings suggest a role for V-ATPase in the regulation of the cell wall stress response and the prevention of endogenous oxidative stress in response to ethanol.IMPORTANCEThe yeastSaccharomyces cerevisiaehas been widely used in the alcoholic fermentation industry. Among the environmental stresses that yeast cells encounter during the process of alcoholic fermentation, ethanol is a major stress factor that inhibits yeast growth and viability, eventually leading to fermentation arrest. This study provides evidence for the molecular mechanisms of ethanol tolerance, which is a desirable characteristic for yeast strains used in alcoholic fermentation. The results revealed that straight-chain alcohols induced cytosolic and vacuolar acidification through their membrane-permeabilizing effects. Contrary to expectations, a role for V-ATPase in the regulation of the cell wall stress response and the prevention of endogenous oxidative stress, but not in the maintenance of intracellular pH, seems to be important for protecting yeast cells against ethanol stress. These findings will expand our understanding of the mechanisms of ethanol tolerance and provide promising clues for the development of ethanol-tolerant yeast strains.

Sign in / Sign up

Export Citation Format

Share Document