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Open Biology Apr 2022The biosynthesis of sterols is critical for the majority of eukaryotes; however, some organisms lack this pathway, including most oomycetes. spp. are sterol...
The biosynthesis of sterols is critical for the majority of eukaryotes; however, some organisms lack this pathway, including most oomycetes. spp. are sterol auxotrophic but, remarkably, have retained a few genes encoding enzymes in the sterol biosynthesis pathway. Here, we show that a gene in predicted to encode Δ7-sterol reductase, displays multiple functions. When expressed in , PcDHCR7 showed the Δ7-sterol reductase activity. Knocking out in resulted in loss of the capacity to transform ergosterol into brassicasterol, which means PcDHCR7 has the Δ7-sterol reductase activity in itself This enables to transform sterols recruited from the environment for better use. The biological characteristics of transformants were compared with those of the wild-type strain and a complemented transformant, and the results showed that plays a key role in mycelium development and pathogenicity of zoospores. Further analysis of the transcriptome indicated that the expression of many genes changed in the transformant, which involve in different biological processes. It is possible that compensates for the defects caused by the loss of by remodelling its transcriptome.
Topics: Mycelium; Oxidoreductases; Phytophthora; Plant Diseases; Sterols; Virulence
PubMed: 35382565
DOI: 10.1098/rsob.210282 -
International Journal of Molecular... Nov 2014For screening anti-aging samples from marine natural products, K6001 yeast strain was employed as a bioassay system. The active mussel extract was separated to give an...
For screening anti-aging samples from marine natural products, K6001 yeast strain was employed as a bioassay system. The active mussel extract was separated to give an active sterol fraction (SF). SF was further purified, and four sterol compounds were obtained. Their structures were determined to be cholesterol (CHOL), brassicasterol, crinosterol, and 24-methylenecholesterol. All compounds showed similar anti-aging activity. To understand the action mechanism involved, anti-oxidative experiments, reactive oxygen species (ROS) assays, and malondialdehyde (MDA) tests were performed on the most abundant compound, CHOL. Results indicated that treatment with CHOL increases the survival rate of yeast under oxidative stress and decreases ROS and MDA levels. In addition, mutations of uth1, skn7, sod1, and sod2, which feature a K6001 background, were employed and the lifespans of the mutations were not affected by CHOL. These results demonstrate that CHOL exerts anti-aging effects via anti-oxidative stress. Based on the connection between neuroprotection and anti-aging, neuroprotective experiments were performed in PC12 cells. Paraquat was used to induce oxidative stress and the results showed that the CHOL and SF protect the PC12 cells from the injury induced by paraquat. In addition, these substance exhibited nerve growth factor (NGF) mimic activities again confirmed their neuroprotective function.
Topics: Aging; Animals; Antioxidants; Gene Expression Regulation; Malondialdehyde; Mutation; Mytilidae; Neuroprotective Agents; Oxidation-Reduction; PC12 Cells; Rats; Reactive Oxygen Species; Saccharomyces cerevisiae; Sterols
PubMed: 25429428
DOI: 10.3390/ijms151221660 -
Journal of Fungi (Basel, Switzerland) Aug 2021is a phytopathogenic fungus. To know more about the metabolites produced by this fungus, the objective of this work was to identify, isolate and characterize substances...
is a phytopathogenic fungus. To know more about the metabolites produced by this fungus, the objective of this work was to identify, isolate and characterize substances present in extracts of the growth broth and mycelium, using gas chromatography with mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR). It was also objective to evaluate the antibacterial activity of the extracts. Among the compounds identified, fatty acids, esters, and steroids can be highlighted. The main compounds identified are 9-hexadecenoic, hexadecenoic, oleic, octadecanoic, lauric, myristic, palmitic, doceno-13-enoic, stearic, linoleic, and nonadecanoic acids present in almost all extracts. For the antibacterial activity, the broth microdilution method was used. The ethyl acetate extract of the mycelium presented inhibitory concentrations (MICs) against the bacterium (100 μg mL) and (200 μg mL). Finally, two steroids were isolated and identified in the hexane extract of mycelium: ergosta-6,22-dien-3β,5α,8α-triol and brassicasterol.
PubMed: 34575718
DOI: 10.3390/jof7090680 -
PloS One 2012Fungal extracellular vesicles are able to cross the cell wall and transport molecules that help in nutrient acquisition, cell defense, and modulation of the host defense...
BACKGROUND
Fungal extracellular vesicles are able to cross the cell wall and transport molecules that help in nutrient acquisition, cell defense, and modulation of the host defense machinery.
METHODOLOGY/PRINCIPAL FINDINGS
Here we present a detailed lipidomic analysis of extracellular vesicles released by Paracoccidioides brasiliensis at the yeast pathogenic phase. We compared data of two representative isolates, Pb3 and Pb18, which have distinct virulence profiles and phylogenetic background. Vesicle lipids were fractionated into different classes and analyzed by either electrospray ionization- or gas chromatography-mass spectrometry. We found two species of monohexosylceramide and 33 phospholipid species, including phosphatidylcholine, phosphatidylethanolamine, phosphatidic acid, phosphatidylserine, phosphatidylinositol, and phosphatidylglycerol. Among the phospholipid-bound fatty acids in extracellular vesicles, C181 predominated in Pb3, whereas C18:2 prevailed in Pb18. The prevalent sterol in Pb3 and Pb18 vesicles was brassicasterol, followed by ergosterol and lanosterol. Inter-isolate differences in sterol composition were observed, and also between extracellular vesicles and whole cells.
CONCLUSIONS/SIGNIFICANCE
The extensive lipidomic analysis of extracellular vesicles from two P. brasiliensis isolates will help to understand the composition of these fungal components/organelles and will hopefully be useful to study their biogenesis and role in host-pathogen interactions.
Topics: Cerebrosides; Gas Chromatography-Mass Spectrometry; Paracoccidioides; Phosphatidic Acids; Phosphatidylcholines; Phosphatidylglycerols; Phosphatidylinositols; Phosphatidylserines; Phospholipids; Secretory Vesicles
PubMed: 22745761
DOI: 10.1371/journal.pone.0039463 -
Frontiers in Plant Science 2017Sterol glycosyltransferases (SGTs) catalyze the glycosylation of the free hydroxyl group at C-3 position of sterols to produce sterol glycosides. Glycosylated sterols...
Sterol glycosyltransferases (SGTs) catalyze the glycosylation of the free hydroxyl group at C-3 position of sterols to produce sterol glycosides. Glycosylated sterols and free sterols are primarily located in cell membranes where in combination with other membrane-bound lipids play a key role in modulating their properties and functioning. In contrast to most plant species, those of the genus contain very high levels of glycosylated sterols, which in the case of tomato may account for more than 85% of the total sterol content. In this study, we report the identification and functional characterization of the four members of the tomato ( cv. Micro-Tom) gene family. Expression of recombinant SlSGT proteins in cells and leaves demonstrated the ability of the four enzymes to glycosylate different sterol species including cholesterol, brassicasterol, campesterol, stigmasterol, and β-sitosterol, which is consistent with the occurrence in their primary structure of the putative steroid-binding domain found in steroid UDP-glucuronosyltransferases and the UDP-sugar binding domain characteristic for a superfamily of nucleoside diphosphosugar glycosyltransferases. Subcellular localization studies based on fluorescence recovery after photobleaching and cell fractionation analyses revealed that the four tomato SGTs, like the Arabidopsis SGTs UGT80A2 and UGT80B1, localize into the cytosol and the PM, although there are clear differences in their relative distribution between these two cell fractions. The genes have specialized but still largely overlapping expression patterns in different organs of tomato plants and throughout the different stages of fruit development and ripening. Moreover, they are differentially regulated in response to biotic and abiotic stress conditions. expression increases markedly in response to osmotic, salt, and cold stress, as well as upon treatment with abscisic acid and methyl jasmonate. Stress-induced expression largely parallels that of . On the contrary, and expression remains almost unaltered under the tested stress conditions. Overall, this study contributes to broaden the current knowledge on plant SGTs and provides support to the view that tomato SGTs play overlapping but not completely redundant biological functions involved in mediating developmental and stress responses.
PubMed: 28649260
DOI: 10.3389/fpls.2017.00984 -
Biochimica Et Biophysica Acta Feb 2013Sugars are recognized as signaling molecules regulating the biosynthesis of secondary metabolites in plants. Here, a modulatory effect of sugars on dolichol and...
Sugars are recognized as signaling molecules regulating the biosynthesis of secondary metabolites in plants. Here, a modulatory effect of sugars on dolichol and phytosterol profiles was noted in the hairy roots of Arabidopsis thaliana. Arabidopsis roots contain a complex dolichol mixture comprising three groups ('families') of dolichols differing in the chain-length. These dolichols, especially the longest ones are accompanied by considerable amounts of polyprenols of the same length. The spectrum of polyisoprenoid alcohols, i.e. dolichols and polyprenols, was dependent on sugar type (glucose or sucrose) and its concentration in the medium. Among the long-chain dolichols Dol/Pren-20 (dolichol or prenol molecule composed of 20 isoprene residues) and Dol/Pren-23 were the main components at 0.5% and 2% glucose, respectively. Moreover, the ratio of polyprenols versus respective dolichols was also modulated by sugar in this group of polyisoprenoids, with polyprenols dominating at 3% sucrose and dolichols at 2% glucose. Glucose concentration affected the expression level of genes encoding cis-prenyltransferases, enzymes responsible for elongation of the polyisoprenoid chain. The most abundant phytosterols of the A. thaliana roots, β-sitosterol, stigmasterol and campesterol, were accompanied by corresponding stanols and traces of brassicasterol, stigmast-4,22-dien-3-one and stigmast-4-en-3-one. Similar to the polyisoprenoids, sterol profile responded to the sugar present in the medium, β-sitosterol dominating in roots grown on 3% or lower glucose concentrations and stigmasterol in 3% sucrose. These results indicate an involvement of sugar signaling in the regulation of cis-prenyltransferases and phytosterol pathway enzymes.
Topics: Arabidopsis; Biological Availability; Carbohydrate Metabolism; Phytosterols; Plant Roots; Terpenes
PubMed: 23178167
DOI: 10.1016/j.bbalip.2012.11.006 -
Heliyon Mar 2020In the present study, modified extraction methods using supercritical CO were investigated in order to obtain high-added value compounds from rapeseed oil deodorizer...
In the present study, modified extraction methods using supercritical CO were investigated in order to obtain high-added value compounds from rapeseed oil deodorizer distillate and comparisons were done with modified Soxhlet extraction (solvent extraction + silica). For supercritical fluid extraction (SFE), the optimal extraction parameters were temperature of 40 °C, pressure of 350 bar (for phytosterols), 400 bar (for tocopherol), 5 wt% ethanol as co-solvent, and saponification pretreatment. The optimized SFE procedure led to the recovery of three main phytosterols (50 wt % β-sitosterol, 23.91 wt % Brassicasterol, and 36.25 wt % Campesterol) and only α-tocopherol. Moreover, there was no synergistic effect with saponification pretreatment + co-solvent and the efficiency and concentration of target compounds were less than supercritical CO + co-solvent. Also, comparative Data showed that the efficiency of phytosterols and tocopherols was approximately three times higher ( < 0.05) in SFE relative to modified Soxhlet extraction. Furthermore, the use of ethanol (5 wt %) as co-solvent, improved phytosterols and tocopherol efficiency and purity. The SFE technique offers various advantages over the modified Soxhlet extraction technique, including increasing the solubility of tocopherols and sterols by using CO+ co-solvent, minimized usage of toxic organic solvents and increased purity of extracted products.
PubMed: 32258458
DOI: 10.1016/j.heliyon.2020.e03592 -
BMC Bioinformatics Apr 2015Sterol glycosyltransferases (SGTs) are ubiquitous but one of the most diverse group of enzymes of glycosyltransferases family. Members of this family modulate physical... (Comparative Study)
Comparative Study
BACKGROUND
Sterol glycosyltransferases (SGTs) are ubiquitous but one of the most diverse group of enzymes of glycosyltransferases family. Members of this family modulate physical and chemical properties of secondary plant products important for various physiological processes. The role of SGTs has been demonstrated in the biosynthesis of pharmaceutically important molecules of medicinal plants like Withania somnifera.
RESULTS
Analysis suggested conserved behaviour and high similarity in active sites of WsSGTs with other plant GTs. Substrate specificity of WsSGTs were analysed through docking performance of WsSGTs with different substrates (sterols and withanolides). Best docking results of WsSGTL1 in the form of stable enzyme-substrate complex having lowest binding energies were obtained with brassicasterol, transandrosteron and WsSGTL4 with solasodine, stigmasterol and 24-methylene cholesterol.
CONCLUSION
This study reveals topological characters and conserved nature of two SGTs from W. somnifera (WsSGTs) i.e. WsSGTL1 and WsSGTL4. However, besides being ubiquitous in nature and with broad substrate specificity, difference between WsSGTL1 and WsSGTL4 is briefly described by difference in stability (binding energy) of enzyme-substrate complexes through comparative docking.
Topics: Amino Acid Sequence; Catalytic Domain; Glycosyltransferases; Molecular Docking Simulation; Molecular Sequence Data; Protein Conformation; Sequence Homology, Amino Acid; Sterols; Substrate Specificity; Withania; Withanolides
PubMed: 25888493
DOI: 10.1186/s12859-015-0563-7 -
ACS Omega Feb 2024By dry crystallization, concentrations of unsaturated fatty acids and bioactive compounds can be increased in olein and super-olein fractions in vegetable oils. Among...
Fatty Acid Composition, Phenolic Compounds, Phytosterols, and Lipid Oxidation of Single- and Double-Fractionated Olein of Safflower Oil Produced by Low-Temperature Crystallization.
By dry crystallization, concentrations of unsaturated fatty acids and bioactive compounds can be increased in olein and super-olein fractions in vegetable oils. Among all sources of vegetable oils, safflower oil (SO) possesses the maximum linoleic acid content. To boost the industrial applications of SO, two variants were produced by single- and two-stage crystallization. This study aimed to determine the fatty acid compositions, phenolic compounds, phytosterols, and oxidative stability of fractionated olein (OF) and double-fractionated olein (DFO) produced by dry crystallization. For this, SO was cooled to -45 °C and filtered, the filtrate was denoted as single-fractionated olein (OF), and 40% of this section was taken for analytical purposes, while the remaining 60% was again cooled to -70 °C and filtered, and the filtrate was denoted as double-fractionated olein (DFO). Unfractionated safflower (SO) was used as a control, filled in amber glass bottles, and stored at 20-25 °C for 90 days. Fatty acid compositions and phytosterols were determined by gas chromatography-mass spectrometry (GC-MS). Phenolic compounds and induction periods were determined by high-performance liquid chromatography (HPLC) and Rancimat. GC-MS analysis revealed that the C18:2 contents of SO, OF, and DFO were 77.63 ± 0.82, 81.57 ± 0.44, and 89.26 ± 0.48 mg/100 g ( < 0.05), respectively. The C18:1 contents of SO, OF, and DFO were 6.38 ± 0.19, 7.36 ± 0.24, and 9.74 ± 0.32 mg/100 g ( < 0.05), respectively. HPLC analysis showed that phenolic compounds were concentrated in the low-melting-point fractions. In DFO, concentrations of tyrosol, rutin, vanillin, ferulic acid, and sinapic acid were 57.36 ± 0.12, 129.45 ± 0.38, 165.11 ± 0.55, 183.61 ± 0.15, 65.94 ± 0.11, and 221.75 ± 0.29 mg/100 g, respectively. In SO, concentrations of tyrosol, rutin, vanillin, ferulic acid, and sinapic acid were 24.79 ± 0.08, 78.93 ± 0.25, 115.67 ± 0.41, 34.89 ± 0.51, and 137.26 ± 0.08 mg/100 g, respectively. In OF, concentrations of tyrosol, rutin, vanillin, ferulic acid, and sinapic acid were 35.96 ± 0.20, 98.69 ± 0.64, 149.14 ± 0.13, 57.53 ± 0.74, and 188.28 ± 0.82 mg/100 g, respectively. The highest concentrations of brassicasterol, campesterol, stigmasterol, β-sitosterol, avenasterol, stigmastenol, and avenasterol were noted in DFO followed by OF and SO. The total antioxidant capacities of SO, OF, and DFO were 54.78 ± 0.12, 71.36 ± 0.58, and 86.44 ± 0.28%, respectively. After the end of the storage time, the peroxide values (POVs) of SO, OF, and DFO stored for 3 months were 0.68, 0.85, and 1.16 mequiv O/kg, respectively, with no difference in the free fatty acid content.
PubMed: 38371827
DOI: 10.1021/acsomega.3c08099 -
Molecules (Basel, Switzerland) Nov 2019Sterols are widely distributed in nature from lipids in organisms to sediments. As a conventional method, extraction and derivatization with TMS have been applied for...
Sterols are widely distributed in nature from lipids in organisms to sediments. As a conventional method, extraction and derivatization with TMS have been applied for sterol analysis, requiring a long preparation time for gas chromatography-mass spectrometry analysis. In this study, for sterol analysis, thermochemolysis using tetramethylammonium hydroxide (TMAH) was applied. This method performs hydrolysis and methylation simultaneously; thus, free and ether-bonding sterols can be analyzed as sterol methyl ethers in a relatively short time period. A sediment sample from a tideland (the Yatsu tideland, Japan) was analyzed using the TMAH method, and we detected more than 10 sterols, which include cholest-5-en-3-ol (cholesterol), 24-ethylcholest-5-en-3-ol (sitosterol), 24-methylcholesta-5,22-3-ol (brassicasterol), 24-ethylcholesta-5,24(28)-dien-3-ol (isofucosterol), 4,23,24-trimethyl-5(H)-cholest-22-en-3- ol (dinosterol), and 5(H)-cholestan-3-ol (coprostanol). The detection of the various sterols can be attributed to multiple natural and artificial sources around the Yatsu tideland. In this paper, the mass spectra of these sterols are provided together with an interpretation of their fragmentation patterns. Additionally, the fecal pollution in the Yatsu tideland is discussed in the context of the detection of coprostanol.
Topics: Cholestanol; Cholestenes; Gas Chromatography-Mass Spectrometry; Geologic Sediments; Quaternary Ammonium Compounds
PubMed: 31703423
DOI: 10.3390/molecules24224040