scholarly journals Fluidization of Membrane Lipids Enhances the Tolerance of Saccharomyces cerevisiae to Freezing and Salt Stress

2006 ◽  
Vol 73 (1) ◽  
pp. 110-116 ◽  
Author(s):  
Sonia Rodríguez-Vargas ◽  
Alicia Sánchez-García ◽  
Jose Manuel Martínez-Rivas ◽  
Jose Antonio Prieto ◽  
Francisca Randez-Gil
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Fatty Acids ◽  
Unsaturated Fatty Acids ◽  
Membrane Lipids ◽  
Fatty Acid Content ◽  
Unsaturation Index ◽  
Monounsaturated Fatty Acids ◽  
Yeast Cells ◽  
Proper Function ◽  
Wild Type

ABSTRACT Unsaturated fatty acids play an essential role in the biophysical characteristics of cell membranes and determine the proper function of membrane-attached proteins. Thus, the ability of cells to alter the degree of unsaturation in their membranes is an important factor in cellular acclimatization to environmental conditions. Many eukaryotic organisms can synthesize dienoic fatty acids, but Saccharomyces cerevisiae can introduce only a single double bond at the Δ9 position. We expressed two sunflower (Helianthus annuus) oleate Δ12 desaturases encoded by FAD2-1 and FAD2-3 in yeast cells of the wild-type W303-1A strain (trp1) and analyzed their effects on growth and stress tolerance. Production of the heterologous desaturases increased the content of dienoic fatty acids, especially 18:2Δ9,12, the unsaturation index, and the fluidity of the yeast membrane. The total fatty acid content remained constant, and the level of monounsaturated fatty acids decreased. Growth at 15°C was reduced in the FAD2 strains, probably due to tryptophan auxotrophy, since the trp1 (TRP1) transformants that produced the sunflower desaturases grew as well as the control strain did. Our results suggest that changes in the fluidity of the lipid bilayer affect tryptophan uptake and/or the correct targeting of tryptophan transporters. The expression of the sunflower desaturases, in either Trp+ or Trp− strains, increased NaCl tolerance. Production of dienoic fatty acids increased the tolerance to freezing of wild-type cells preincubated at 30°C or 15°C. Thus, membrane fluidity is an essential determinant of stress resistance in S. cerevisiae, and engineering of membrane lipids has the potential to be a useful tool of increasing the tolerance to freezing in industrial strains.

scholarly journals LIPIDS OF CARDIOMYOCYTES MEMBRANES STRUCTURES IN RATS AT HYPOBIOSIS

2016 ◽  
Vol 1 ◽  
pp. 3-8
Author(s):  
Svitlana Khyzhnyak ◽  
Svitlana Midyk ◽  
Serhii Sysoliatin ◽  
Olena Laposha
Keyword(s):  
Fatty Acids ◽  
Unsaturated Fatty Acids ◽  
Membrane Lipids ◽  
Neutral Lipids ◽  
Fatty Acid Content ◽  
Biologically Active ◽  
Membrane Phospholipids ◽  
Internal Membrane ◽  
Regulatory Systems ◽  
Artificial Hypobiosis

There was studied an influence of artificial hypobiosis in the conditions of hypoxia-hypercarnia in rats on the quantity of neutral lipids, phospholipids and its fatty acids in membranes structures of cardiomyocytes (microsomes and internal membranes of mitochondria). The received results – the content of lipids, individual phospholipids, cholesterol testify to the modification of lipid component of cardiomyocytes mitochondria internal membrane (less the microsomal fraction) that characterizes modulation of cellular membranes structural-functional state. There was noticed the possibility of attraction of membrane phospholipids (sphingomyelin, phosphatidylserine and phosphatidylinositol) to the signal ways activation at hypobiosis. There was revealed redistribution of fatty acids of mitochondria internal membrane at hypobiosis that leads to increase of the level of unsaturated fatty acids. There was noticed the possibility of participation of monoenic unsaturated fatty acids in protection of cellular structures from oxidizing stress and increase of the content of arachidonic and docosahexaenoic acids – precursors of biologically active substances – can be connected with its attraction to regulatory systems at hypobiosis. There is presupposed that the state of artificial hypobiosis is characterized with stress-reaction that leads to optimal reconstruction of lipid and fatty acid content of membrane lipids directed on support of cardiomyocytes functional activity.

Lipid nutrition of Saccharomyces cerevisiae in winemaking

2004 ◽  
Vol 50 (9) ◽  
pp. 669-674 ◽  
Author(s):  
Simona Belviso ◽  
Laura Bardi ◽  
Alessandra Biondi Bartolini ◽  
Mario Marzona
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Acetic Acid ◽  
Cell Growth ◽  
Acid Production ◽  
Unsaturated Fatty Acids ◽  
Membrane Lipids ◽  
Synthetic Medium ◽  
Wine Industry ◽  
Yeast Cells ◽  
Acetic Acid Production

Biosynthesis of cell membrane lipids is a crucial metabolic pathway for the growth and viability of eucaryotic microorganisms. In Saccharomyces cerevisiae, unsaturated fatty acids and ergosterol synthesis needs molecular oxygen. Stuck and sluggish fermentations are related to this aspect of metabolism and constitute a major problem in the wine industry. Anaerobiosis, when lipids are not available in the growth medium, highly stresses cells. They release lipid biosynthesis metabolites and soon cease to multiply. This paper describes an investigation of the nutritional role of exogenous lipids from inactivated yeast cells (IYCs). Fermentations were carried out in a nitrogen-rich synthetic medium similar to grape juice with glucose and fructose as carbon sources, without lipid sources, and in anaerobiosis. The effect of the addition of IYC was assessed. Cell growth, cell lipid composition, glucose and fructose consumption, and acetic acid production were measured during fermentation. Addition of IYC boosted cell growth and sugar consumption, whereas acetic acid production decreased. Biomass yield was influenced by ergosterol availability and increased when IYCs were added. Fatty acid composition of yeast cells was changed by IYC addition.Key words: fermentation, lipids, nutrition, Saccharomyces cerevisiae, wine.

Sensitivity of Saccharomyces cerevisiae to tannic acid is due to iron deprivation

2001 ◽  
Vol 47 (4) ◽  
pp. 290-293 ◽  
Author(s):  
T Wauters ◽  
D Iserentant ◽  
H Verachtert
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Fatty Acids ◽  
Growth Rate ◽  
Tannic Acid ◽  
Unsaturated Fatty Acids ◽  
Acid Resistance ◽  
Maximal Growth ◽  
Wild Type ◽  
Iron Deprivation ◽  
Maximal Growth Rate

Tannic acid inhibited the growth of the yeast Saccharomyces cerevisiae. Growth medium supplementation with more nitrogen or metal ions showed that only iron ions could restore the maximal growth rate of S. cerevisiae. Tannic acid resistant mutants were previously isolated by screening for tannic acid resistance and were all cytoplasmic petite mutants. While the wild type was very sensitive to iron deprivation conditions when grown in aerobic conditions, the mutants, whether grown aerobically or anaerobically, showed the same growth rate under iron-limited conditions as under iron-repleted conditions. Also, the wild type grown anaerobically was not affected by iron-limited conditions. Cytoplasmic petite mutants obtained by ethidium bromide mutagenesis behaved like the other mutants. During iron limitation, the wild type showed a reduced oxygen uptake rate. Maximal growth rate of the wild type in iron-limited conditions could be restored by the addition to the media of unsaturated fatty acids and sterol. Iron deprivation caused by tannic acid may thus affect the synthesis of a functional respiratory chain as well as the synthesis of unsaturated fatty acids and (or) sterol.Key words: Saccharomyces cerevisiae, tannic acid resistance, iron deprivation, cytoplasmic petite mutant.

Effects of unsaturated fatty acid deprivation on neutral lipid synthesis in Saccharomyces cerevisiae

1982 ◽  
Vol 152 (2) ◽  
pp. 747-756
Author(s):  
T M Buttke ◽  
A L Pyle
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Fatty Acids ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Lipid Metabolism ◽  
Cell Growth ◽  
Unsaturated Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Lipid Synthesis ◽  
Yeast Cells

The effects of unsaturated fatty acid deprivation on lipid synthesis in Saccharomyces cerevisiae strain GL7 were determined by following the incorporation of [14C]acetate. Compared to yeast cells grown with oleic acid, unsaturated fatty acid-deprived cells contained 200 times as much 14C label in squalene, with correspondingly less label in 2,3-oxidosqualene and 2,3;22,23-dioxidosqualene. Cells deprived of either methionine or cholesterol did not accumulate squalene, demonstrating that the effect of unsaturated fatty acid starvation on squalene oxidation was not due to an inhibition of cell growth. Cells deprived of olefinic supplements displayed additional changes in lipid metabolism: (i) an increase in 14C-labeled diacylglycerides, (ii) a decrease in 14C-labeled triacylglycerides, and (iii) increased levels of 14C-labeled decanoic and dodecanoic fatty acids. The changes in squalene oxidation and acylglyceride metabolism in unsaturated fatty acid-deprived cells were readily reversed by adding oleic acid. Pulse-chase studies demonstrated that the [14C]squalene and 14C-labeled diacylglycerides which accumulated during starvation were further metabolized when cells were resupplemented with oleic acid. These results demonstrate that unsaturated fatty acids are essential for normal lipid metabolism in yeasts.

scholarly journals Effect of fatty acid content on the level of cottonseed colonization by fungi

2011 ◽  
Vol 48 (2) ◽  
pp. 125-137 ◽  
Author(s):  
Aly Aly ◽  
Ezzat Hussein ◽  
Moawad Omar ◽  
Ibrahim El-Abbasi ◽  
Kamel Abd-Elsalam
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Acid Content ◽  
Unsaturated Fatty Acids ◽  
Fatty Acid Content ◽  
Monounsaturated Fatty Acids ◽  
Gas Liquid Chromatography ◽  
Rhizopus Stolonifer ◽  
Qualitative And Quantitative ◽  
Quantitative Estimates

Effect of fatty acid content on the level of cottonseed colonization by fungiNon-sterilized seeds of 12 Egyptain cotton (Gossypium barbadenseL.) genotypes were examined for qualitative and quantitative estimates of seed-borne fungi.Rhizopus stolonifer(39.7%),Aspergillus niger(33.5%), andPenicilliumsp. (23.3%) were the most predominant fungi isolated from the seeds. Other fungi occurred at frequencies that ranged from 0.3 to 17.7%. Gas-liquid chromatography (GLC) analysis of fatty acid composition of the seeds revealed the presence of the following fatty acids: caproic, caprylic, capric, lauric, myristic, palmitic, margaric, stearic, oleic, linoleic, and linolenic. The total mean percentage of the monounsaturated fatty acids was 59.11%, while that of the unsaturated fatty acids was 16.72%. Isolation frequencies ofAlternaria alternata, A. flavus, A. nigerwere not significantly correlated with the content of any fatty acid. Isolation frequencies of the other fungi were significantly correlated with the content of 1-2 fatty acids.Cladosporiumsp. was a notable exception because its isolation frequency was significantly correlated with the content of caproic (r= 0.926,p< 0.01), caprylic (r= 0.638,p< 0.05), palmitic (r= -0.586,p< 0.05), and linoleic acid (r= 0.917,p< 0.01). It was possible to group the isolated fungi into 5 distinct categories based on their sensitivity to the fatty acids (the magnitude ofR2 values). The results of the present investigation suggest that certain fatty acids regulate the colonization of cottonseed by fungi, and that the control of these fungi may be possible by modifying the fatty acid content of the seed.

scholarly journals Enhanced levels of Pis1p (phosphatidylinositol synthase) improve the growth of Saccharomyces cerevisiae cells deficient in Rsp5 ubiquitin ligase

2006 ◽  
Vol 395 (1) ◽  
pp. 173-181 ◽  
Author(s):  
Pawel Kaliszewski ◽  
Thierry Ferreira ◽  
Beata Gajewska ◽  
Anna Szkopinska ◽  
Thierry Berges ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Ubiquitin Ligase ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Fatty Acid Content ◽  
Restrictive Temperature ◽  
Multicopy Plasmid ◽  
Wild Type ◽  
Phosphatidylinositol Synthase

The Rsp5 ubiquitin ligase plays a role in many cellular processes including the biosynthesis of unsaturated fatty acids. The PIS1 (phosphatidylinositol synthase gene) encoding the enzyme Pis1p which catalyses the synthesis of phosphatidylinositol from CDP-diacyglycerol and inositol, was isolated in a screen for multicopy suppressors of the rsp5 temperature sensitivity phenotype. Suppression was allele non-specific. Interestingly, expression of PIS1 was 2-fold higher in the rsp5 mutant than in wild-type yeast, whereas the introduction of PIS1 in a multicopy plasmid increased the level of Pis1p 6-fold in both backgrounds. We demonstrate concomitantly that the expression of INO1 (inositol phosphate synthase gene) was also elevated approx. 2-fold in the rsp5 mutant as compared with the wild-type, and that inositol added to the medium improved growth of rsp5 mutants at a restrictive temperature. These results suggest that enhanced phosphatidylinositol synthesis may account for PIS1 suppression of rsp5 defects. Analysis of lipid extracts revealed the accumulation of saturated fatty acids in the rsp5 mutant, as a consequence of the prevention of unsaturated fatty acid synthesis. Overexpression of PIS1 did not correct the cellular fatty acid content; however, saturated fatty acids (C16:0) accumulated preferentially in phosphatidylinositol, and (wild-type)-like fatty acid composition in phosphatidylethanolamine was restored.

STUDI PERBANDINGAN PROFIL ASAM LEMAK PADA IKAN SIDAT (Anguilla marmorata) DAN SIDAT (Anguilla bicolor) ASAL DANAU POSO KABUPATEN POSO PROVINSI SULAWESI TENGAH

Biocelebes ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 79-93
Author(s):  
Dewi Muhtiani ◽  
Nurlina Ibrahim ◽  
Jamaluddin Jamaluddin
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Fatty Acid Content ◽  
Acid Methyl Ester ◽  
Monounsaturated Fatty Acids ◽  
Chromatography Method ◽  
Anguilla Marmorata ◽  
Two Samples

Sidat fish (Anguilla marmorata) and Sidat fish (Anguilla bicolor) originate from Poso lake are endemic fish of Central Sulawesi but unknown its nutritional content. This study aims to determine the type, amount of composition and differences in the composition of fatty acids in Sidat fish (Anguilla marmorata) and Sidat fish (Anguilla bicolor). Testing fatty acid composition using Gas Chromatography method by converting fat extraction result into FAME (Fatty Acid Methyl Ester) form. The results showed that the amount of fatty acid content was not significant between the two samples. The fatty acid compositions found in Sidat (Anguilla marmorata) A, B and C fish include saturated fatty acids (2.62%), (2.81%), and (2.6%), monounsaturated fatty acids (1.98% ), (1.99%), and (10.1%), compound unsaturated fatty acids (0.635%), (0.812%), and (2.56%), mean while Sidat fish (Anguilla bicolor)  A, B and C include saturated fatty acids (2.7%), (2.86%), and (12.704%), monounsaturated fatty acids (1.99%), (2.52%), (10.147%), and fatty acids unsaturated compounds (0.693%), (0.86%), and (2.615%).

scholarly journals The effects of altered membrane sterol composition on oxidative phosphorylation in a haem mutant of Saccharomyces cerevisiae

1977 ◽  
Vol 166 (2) ◽  
pp. 287-298 ◽  
Author(s):  
Anne M. Astin ◽  
J. M. Haslam
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Fatty Acids ◽  
Oxidative Phosphorylation ◽  
Unsaturated Fatty Acids ◽  
Membrane Lipids ◽  
Tween 80 ◽  
Growth Efficiency ◽  
Sterol Composition ◽  
Sterol Content

1. The sterol, unsaturated fatty acid and cytochrome contents of cells of a δ-aminolaevulinate synthase mutant of Saccharomyces cerevisiae are manipulated by growing the organism in media containing defined supplements of δ-aminolaevulinate and other porphyrin intermediates. 2. If unsaturated fatty acids are added to the growth medium as Tween 80, sterol content and respiratory cytochromes alone are manipulated. 3. In the presence of δ-aminolaevulinate (10–50mg/1) cells exhibit moderate to high respiratory activity, but growth yields are low, indicating a loss of oxidative phosphorylation. This is associated with the depletion of membrane lipids, either unsaturated fatty acids and sterols together or sterols alone. 4. Sterol depletion leads to the loss of coupled mitochondrial oxidative phosphorylation in vitro. 5. The lesion in oxidative phosphorylation is associated with an increase in the passive permeability of sterol-depleted mitochondria to protons. 6. Arrhenius plots of mitochondrial permeability to protons indicate that the activation energy for proton entry increases as the sterol content of the membranes decreases. 7. Studies on a cytoplasmic petite mutant isolated from strain ole-3, which lacks a functional membrane-bound protein-translocating adenosine triphosphatase, indicate that proton permeability of the petite mitochondria varies as a function of sterol composition in the same way as that of ole-3 grande mitochondria. This indicates that sterols alone are probably directly responsible for the increased proton entry, owing to a reorganization of the lipid in the membrane. 8. Supplemented ole-3 cells with a normal lipid composition and normal or higher than normal respiratory activities have a growth efficiency only 65% of that of the wild-type, indicating that a further lesion in energy metabolism may be present.

scholarly journals The Stearoyl-Coenzyme A Desaturase 1 Is Essential for Virulence and Membrane Stress inCandida parapsilosisthrough Unsaturated Fatty Acid Production

2010 ◽  
Vol 79 (1) ◽  
pp. 136-145 ◽  
Author(s):  
Long Nam Nguyen ◽  
Attila Gacser ◽  
Joshua D. Nosanchuk
Keyword(s):  
Fatty Acids ◽  
Acid Production ◽  
Unsaturated Fatty Acids ◽  
Coenzyme A ◽  
Saturated Fatty Acids ◽  
Yeast Cells ◽  
Wild Type ◽  
Fungal Virulence ◽  
Essential Components ◽  
The Impact

ABSTRACTUnsaturated fatty acids (UFA) are essential components of cells. InSaccharomyces cerevisiae, stearoyl-coenzyme A (CoA) desaturase 1 (OLE1) affects cell viability through the regulation of oleic (18:1) or palmitoleic (16:1) acid production. In this study, we used a targeted gene deletion approach to determine the impact ofOLE1on the emerging human pathogenic fungusCandida parapsilosis. We found that the deletion ofOLE1resulted in an auxotrophic yeast strain (designatedOLE1KO) that required unsaturated fatty acids for growth but not saturated fatty acids. Additionally, the production of UFA byOLE1KO yeast cells was markedly reduced, suggesting that Ole1 is essential for UFA production. In contrast to wild-typeC. parapsilosis, which produced pseudohyphal growth on UFA-supplemented medium agar, pseudohyphal formation in theOLE1KO cells was severely impaired, suggesting that Ole1 regulates morphology. Furthermore, theOLE1KO cells were hypersensitive to various stress-inducing factors, such as salts, SDS, and H2O2, especially at the physiological temperature. The results indicate thatOLE1is essential for the stress response, perhaps through the production of UFA for cell membrane biosynthesis. TheOLE1KO cells also were hypersensitive to human and fetal bovine serum, suggesting that targeting Ole1 could suppress the dissemination of yeast cells in the bloodstream. Murine-like macrophage J774.16 more efficiently killed theOLE1KO yeasts, and significantly larger amounts of nitric oxide were detected in cocultures of macrophages andOLE1KO cells than with wild-type or heterozygous strains. Moreover, the disruption ofOLE1significantly reduced fungal virulence in systemic murine infection. Taken together, these results demonstrate that Ole1 regulates the pathobiology ofC. parapsilosisvia UFA and that theOLE1pathway is a promising antifungal target.

Distinct Modulation of Wild-Type and Selective Gene Mutated Vitamin D Receptor by Essential Poly Unsaturated Fatty Acids

2021 ◽  
Vol 21 ◽  
Author(s):  
Hari Balaji ◽  
Selvaraj Ayyamperuma ◽  
Niladri Saha ◽  
Shyam Sundar Pottabathula ◽  
Jubie Selvaraj ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Vitamin D ◽  
Ligand Binding ◽  
Vitamin D Deficiency ◽  
Binding Affinity ◽  
Unsaturated Fatty Acids ◽  
Binding Domain ◽  
Ligand Binding Domain ◽  
Binding Energies ◽  
Wild Type

: Vitamin-D deficiency is a global concern. Gene mutations in the vitamin D receptor’s (VDR) ligand binding domain (LBD) variously alter the ligand binding affinity, heterodimerization with retinoid X receptor (RXR) and inhibit coactivator interactions. These LBD mutations may result in partial or total hormone unresponsiveness. A plethora of evidence report that selective long chain polyunsaturated fatty acids (PUFAs) including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (AA) bind to the ligand-binding domain of VDR and lead to transcriptional activation. We therefore hypothesize that selective PUFAs would modulate the dynamics and kinetics of VDRs, irrespective bioactive of vitamin-D binding. The spatial arrangements of the selected PUFAs in VDR active site were examined by in-silico docking studies. The docking results revealed that PUFAs have fatty acid structure-specific binding affinity towards VDR. The calculated EPA, DHA & AA binding energies (Cdocker energy) were lesser compared to vitamin-D in wild type of VDR (PDB id: 2ZLC). Of note, the DHA has higher binding interactions to the mutated VDR (PDB id: 3VT7) when compared to the standard Vitamin-D. Molecular dynamic simulation was utilized to confirm the stability of potential compound binding of DHA with mutated VDR complex. These findings suggest the unique roles of PUFAs in VDR activation and may offer alternate strategy to circumvent vitamin-D deficiency.

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