Control of Fatty Acid and Lipid Biosynthesis in Euglena gracilis by Ammonia, Light and DCMU

1972 ◽  
Vol 27 (1) ◽  
pp. 53-61 ◽  
Author(s):  
P. Pohl ◽  
H. Wagner
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
White Light ◽  
Euglena Gracilis ◽  
Fatty Acid Biosynthesis ◽  
Neutral Lipids ◽  
Fluorescent Light ◽  
Low Levels ◽  
High Concentrations ◽  
Monogalactosyl Diglyceride

When Euglena gracilis was grown under white (fluorescent) light in media containing high concentrations of ammonium chloride (more than 0.005%), the main lipids synthesized were monogalactosyl diglyceride, digalactosyl diglyceride, phosphatidyl glycerol, sulfolipid and the all cis △7,10-16:2, △7,10,13-16:3, △4,7,10,13-16:4, △9,12-18:2 and △9,12,15-18:3 fatty acids. At low levels of ammonium (less than 0.002%) these compounds were produced only in small amounts, while neutral lipids, phosphatidyl choline, phosphatidyl ethanolamine and the 14:0, 16:0 and 16:1 fatty acids predominated.When Euglena gracilis was grown in white light in the presence of dichlorophenyldimethylurea (DCMU) or in the dark, fatty acid and lipid biosyntheses followed the same pattern as in white light at low levels of ammonium. Similar results were obtained when nitrate served as the only nitrogen source in the light and in the dark.The results indicate that in Euglena gracilis there are a light independent and a light and ammonium dependent pathway of fatty acid biosynthesis. Both pathways seem to be in association with specific lipids.

Some Evidence for Light-induced Transfers of Fatty Acids in Euglena gracilis

1973 ◽  
Vol 28 (5-6) ◽  
pp. 270-284 ◽  
Author(s):  
P. Pohl
Keyword(s):  
Fatty Acids ◽  
Euglena Gracilis ◽  
Phosphatidyl Choline ◽  
Phosphatidyl Ethanolamine ◽  
Neutral Lipids ◽  
Steady Increase ◽  
Initial Increase ◽  
Phosphatidyl Glycerol ◽  
Subsequent Decrease ◽  
Monogalactosyl Diglyceride

Euglena gracilis was grown in the dark for 12 days. Subsequent incubation with sodium octanoate- l-14C in the dark for 6 hours resulted in a rather specific incorporation of radioactivity into the neutral lipids (primarily wax esters). Upon illumination of these cells in an identical medium without radiocarbon, the radioactivities in the neutral lipids decreased strongly, due to a decrease of the labeled wax acids (mainly 1 4:0) and wax alcohols (mainly C14). The radioactivities in phosphatidyl choline and phosphatidyl ethanolamine increased during the first 24 hours of illumination and thereafter decreased. This was caused by the initial increase and subsequent decrease of the labeled 14:0 and 16:0 acids in phosphatidyl choline and of the 14:0, 16:0 , and 18:1 acids in phosphatidyl ethanolamine. The chloroplast lipids (sulfolipid, phosphatidyl glycerol, monogalactosyl diglyceride, and digalactosyl diglyceride) exhibited a steady increase in radiocarbon content. This was due to an increase of label in the 16:0 fatty acid of the sulfolipid, in the 16:0 and trans3-16:1 fatty acids of the phosphatidyl glycerol, and in the saturated and unsaturated C16 and C18 fatty acids of the monogalactosyl and digalactosyl diglycerides. The labeled fatty acids of the above phospho- and glycolipids had comparably high specific radioactivities. Incorporation of radiocarbon into the last two carbon atoms of their methyl ends, however, was low. The glycerol and sugar moieties of the individual lipids incorporated relatively little radiocarbon. It is concluded that in Euglena gracilis the biosynthesis of long chain fatty acids is associated with specific lipids. Upon illumination, oxidative breakdown of the neutral lipids as well as transfers of fatty acids from the neutral lipids via phosphatidyl choline and phosphatidyl ethanolamine to the chloroplast lipids seem to be induced. The lipids involved appear to function as parts of a “lipid-bridge” for the acyl transfers.

Light-induced Changes of Radioactivities in the 14C-labeled Lipids and Fatty Acids of Dark Grown Euglena gracilis

1973 ◽  
Vol 28 (5-6) ◽  
pp. 264-269 ◽  
Author(s):  
P. Pohl
Keyword(s):  
Fatty Acids ◽  
Euglena Gracilis ◽  
Phosphatidyl Ethanolamine ◽  
Neutral Lipids ◽  
Subsequent Growth ◽  
Strong Decrease ◽  
Phosphatidyl Glycerol ◽  
Main Fatty Acid ◽  
Monogalactosyl Diglyceride ◽  
Induced Changes

Euglena gracilis was grown in the dark for 12 days in a medium containing sodium acetate- 1-14C. The major amount of 14C was incorporated into the neutral lipids. In these compounds myristic acid was the main fatty acid labeled. Subsequent growth in light (70 hours) in an identical medium (containing unlabeled acetate) led to a strong decrease of radiocarbon in the neutral lipids. The radioactivities in phosphatidyl choline and phosphatidyl ethanolamine increased during the first 28 hours of illumination and thereafter decreased. The radioactivities in phosphatidyl glycerol, sulfolipid, monogalactosyl diglyceride and digalactosyl diglyceride increased continously. After 70 hours of illumination, most of the radiocarbon was detected in the saturated and unsaturated C16 and C18 fatty acids of these four lipids. The possibility of light-induced transfers of fatty acids from neutral lipids via phospholipids to the galactolipids is discussed.

Lipid composition of an obligately anaerobic fungus Neocallimastix frontalis isolated from a bovine rumen

1985 ◽  
Vol 31 (5) ◽  
pp. 463-466 ◽  
Author(s):  
Denis R. Body ◽  
Tom Bauchop
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Lipid Composition ◽  
Fatty Acid Biosynthesis ◽  
Neutral Lipids ◽  
Acid Biosynthesis ◽  
Bovine Rumen ◽  
Obligately Anaerobic ◽  
Rumen Fungus ◽  
Neocallimastix Frontalis

The lipid composition of an obligately anaerobic bovine rumen fungus Neocallimastix frontalis, belonging to the Neo-callimasticaceae of the Chytridiomycetes, has been investigated. It consisted of 44% neutral lipids (triacylglycerol, fatty acid, and sterols) and 56% polar lipids. The fatty acid composition of this unusual fungus differed markedly from that of other members of Chytridiomycetes by the absence of long-chain polyenoic fatty acids and by the presence of a large proportion (48%) of a series of cis-monoenoic fatty acids between 14:1 and 24:1. The absence of polyunsaturated fatty acids is explained by the anaerobic life style of this organism. However, the formation of the large proportions of monoenoic fatty acids under anaerobic conditions constitutes a major difference which cannot be explained by known pathways of fatty acid biosynthesis in fungi. This result indicates that N. frontalis differs from other fungi in possessing an anaerobic pathway for monoenoic fatty acid biosynthesis.

scholarly journals The regulation of glyceride synthesis in isolated white-fat cells. The effects of palmitate and lipolytic agents

1972 ◽  
Vol 128 (5) ◽  
pp. 1057-1067 ◽  
Author(s):  
E. D Saggerson
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Fat Cells ◽  
Glyceride Synthesis ◽  
Glucose Incorporation ◽  
High Concentrations ◽  
Stimulation Of

1. 0.5mm-Palmitate stimulated incorporation of [U-14C]glucose into glyceride glycerol and fatty acids in normal fat cells in a manner dependent upon the glucose concentration. 2. In the presence of insulin the incorporation of 5mm-glucose into glyceride fatty acids was increased by concentrations of palmitate, adrenaline and 6-N-2′-O-dibutyryladenosine 3′:5′-cyclic monophosphate up to 0.5mm, 0.5μm and 0.5mm respectively. Higher concentrations of these agents produced progressive decreases in the rate of glucose incorporation into fatty acids. 3. The effects of palmitate and lipolytic agents upon the measured parameters of glucose utilization were similar, suggesting that the effects of lipolytic agents are mediated through increased concentrations of free fatty acids. 4. In fat cells from 24h-starved rats, maximal stimulation of glucose incorporation into fatty acids was achieved with 0.25mm-palmitate. Higher concentrations of palmitate were inhibitory. In fat cells from 72h-starved rats, palmitate only stimulated glucose incorporation into fatty acids at high concentrations of palmitate (1mm and above). 5. The ability of fat cells to incorporate glucose into glyceride glycerol in the presence of palmitate decreased with increasing periods of starvation. 6. It is suggested that low concentrations of free fatty acids stimulate fatty acid synthesis from glucose by increasing the utilization of ATP and cytoplasmic NADH for esterification of these free fatty acids. When esterification of free fatty acids does not keep pace with their provision, inhibition of fatty acid synthesis occurs. Provision of free fatty acids far in excess of the esterification capacity of the cells leads to uncoupling of oxidative phosphorylation and a secondary stimulation of fatty acid synthesis from glucose.

Circulating Ceramides and Sphingomyelins and Risk of Mortality: The Cardiovascular Health Study

2021 ◽  
Author(s):  
Amanda M Fretts ◽  
Paul N Jensen ◽  
Andrew N Hoofnagle ◽  
Barbara McKnight ◽  
Colleen M Sitlani ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Cardiovascular Health ◽  
Health Study ◽  
Cardiovascular Health Study ◽  
Risk Of Death ◽  
Risk Of Mortality ◽  
Increased Risk ◽  
High Concentrations ◽  
Long Chain

Abstract Background Recent studies suggest that associations of ceramides (Cer) and sphingomyelins (SM) with health outcomes differ according to the fatty acid acylated to the sphingoid backbone. The purpose of this study was to assess associations of Cer and SM species with mortality. Methods The study population included participants from the Cardiovascular Health Study (CHS), a community-based cohort of adults aged ≥65 years who were followed from 1992–2015 (n = 4612). Associations of plasma Cer and SM species carrying long-chain (i.e., 16:0) and very-long-chain (i.e., 20:0, 22:0, 24:0) saturated fatty acids with mortality were assessed using Cox proportional hazards models. Results During a median follow-up of 10.2 years, 4099 deaths occurred. High concentrations of Cer and SM carrying fatty acid 16:0 were each associated with an increased risk of mortality. Conversely, high concentrations of several ceramide and sphingomyelin species carrying longer fatty acids were each associated with a decreased risk of mortality. The hazard ratios for total mortality per 2-fold difference in each Cer and SM species were: 1.89 (95% CI), 1.65–2.17 for Cer-16, 0.79 (95% CI, 0.70–0.88) for Cer-22, 0.74 (95% CI, 0.65–0.84) for Cer-24, 2.51 (95% CI, 2.01–3.14) for SM-16, 0.68 (95% CI, 0.58–0.79) for SM-20, 0.57 (95% CI, 0.49–0.67) for SM-22, and 0.66 (0.57–0.75) for SM-24. We found no association of Cer-20 with risk of death. Conclusions Associations of Cer and SM with the risk of death differ according to the length of their acylated saturated fatty acid. Future studies are needed to explore mechanisms underlying these relationships.

scholarly journals Observations on the nature and origin of lipids in the small intestine of the sheep

1968 ◽  
Vol 22 (2) ◽  
pp. 237-246 ◽  
Author(s):  
Aileen M. Lennox ◽  
A. K. Lough ◽  
G. A. Garton
Keyword(s):  
Fatty Acids ◽  
Small Intestine ◽  
Fatty Acid ◽  
Bile Acids ◽  
Neutral Lipids ◽  
Intestinal Lumen ◽  
Total Lipids ◽  
Total Fatty Acids ◽  
Proportional Contribution ◽  
Conjugated Bile Acids

1. Total lipids were extracted from digesta obtained from the rumen, abomasum and upper small intestine (jejunum) of each of four slaughtered sheep. The lipids were fractionated into unesterified fatty acids, neutral lipids and phospholipids and the proportional contribution of each fraction to the total fatty acids was determined.2. The contribution made by phospholipids to the total fatty acids in the digesta showed a marked increase in the samples from the small intestine compared with those from the rumen and abomasum. This increase was apparently due to the presence of biliary phospholipids.3. Total lipids and conjugated bile acids were extracted from sheep bile, the lipids were fractionated and their fatty-acid composition was determined. Phospholipids predominated and these consisted mainly of phosphatidylcholine, together with some lysophosphatidylcholine.4. Both phospholipids contained significant amounts of unsaturated C18 components which could account, at least in part, for the previously reported increament to the proportion of these acids in the digesta when it enters the upper jejunum.5. The overall fatty acid compositions of the two biliary phospholipids were very similar and, in common with other naturally occurring phosphatidylcholines, the fatty acids present in position 2 of the phosphatidylcholine of bile were found to consist almost entirely of unsaturated components.6. Total lipids and conjugated bile acids were extracted from samples of digesta obtained from three sheep with cannulas in different positions in the jejunum. Analysis of the lipids indicated that biliary phospholipids, in particular phosphatidylcholine, underwent progressive hydrolysis in the intestinal lumen.7. The distribution of conjugated bile acids, unesterified fatty acids and phospholipids between the solid (particulate) and liquid (micellar) phases of the intestinal digesta was determined. These chyme constituents were, for the most part, associated with the particulate matter and thus, at any given time, it appears that only a small fraction of the total fatty acids is available for absorption in micellar form. It is suggested that the micellar solubilization of fatty acids may be facilitated by the presence of lysophosphatidylcholine.

scholarly journals The same rat Δ6-desaturase not only acts on 18- but also on 24-carbon fatty acids in very-long-chain polyunsaturated fatty acid biosynthesis

2002 ◽  
Vol 364 (1) ◽  
pp. 49-55 ◽  
Author(s):  
Sabine D'ANDREA ◽  
Hervé GUILLOU ◽  
Sophie JAN ◽  
Daniel CATHELINE ◽  
Jean-Noël THIBAULT ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Fatty Acid Biosynthesis ◽  
Chain Polyunsaturated Fatty Acid ◽  
Acid Biosynthesis ◽  
Highly Unsaturated Fatty Acids ◽  
Long Chain ◽  
Δ6 Desaturase

The recently cloned Δ6-desaturase is known to catalyse the first step in very-long-chain polyunsaturated fatty acid biosynthesis, i.e. the desaturation of linoleic and α-linolenic acids. The hypothesis that this enzyme could also catalyse the terminal desaturation step, i.e. the desaturation of 24-carbon highly unsaturated fatty acids, has never been elucidated. To test this hypothesis, the activity of rat Δ6-desaturase expressed in COS-7 cells was investigated. Recombinant Δ6-desaturase expression was analysed by Western blot, revealing a single band at 45kDa. The putative involvement of this enzyme in the Δ6-desaturation of C24:5n-3 to C24:6n-3 was measured by incubating transfected cells with C22:5n-3. Whereas both transfected and non-transfected COS-7 cells were able to synthesize C24:5n-3 by elongation of C22:5n-3, only cells expressing Δ6-desaturase were also able to produce C24:6n-3. In addition, Δ6-desaturation of [1-14C]C24:5n-3 was assayed invitro in homogenates from COS-7 cells expressing Δ6-desaturase or not, showing that Δ6-desaturase catalyses the conversion of C24:5n-3 to C24:6n-3. Evidence is therefore presented that the same rat Δ6-desaturase catalyses not only the conversion of C18:3n-3 to C18:4n-3, but also the conversion of C24:5n-3 to C24:6n-3. A similar mechanism in the n-6 series is strongly suggested.

scholarly journals Fatty Acids Profiles of Stipe and Blade from the Norwegian Brown Macroalga Laminaria hyperborea, Using Off-Line SPE and GC-MS

2016 ◽  
Author(s):  
Lena Oksdøl Foseid ◽  
Hanne Devle ◽  
Yngve Stenstrøm ◽  
Carl Fredrik Naess-Andresen ◽  
Dag Ekeberg
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Neutral Lipids ◽  
Methyl Esters ◽  
Lipid Fraction ◽  
Environmental Benefits ◽  
Laminaria Hyperborea ◽  
Alpha Linolenic Acid ◽  
Lipid Fractions

A thorough analysis and comparison of the fatty acid profiles of stipe and blade from Laminaria hyperborea, a kelp species found in the northern Atlantic, is presented. Lipids were extracted and fractionated into neutral lipids, free fatty acids and polar lipids, then derivatized to fatty acid methyl esters prior to GC-MS analysis. A total of 42 fatty acids were identified and quantified, including the n-3 fatty acids α-linolenic acid, stearidonic acid and eicosapentaenoic acid. An n-6/n-3 ratio of 0.8:1 was found in blade and 3.5:1 in stipe, respectively. The ratios vary between the lipid fractions within stipe and blade, with the lowest ratio in the polar lipid fraction of blade. The fatty acid amounts are higher in blade than in stipe, and the highest amounts of n-3 fatty acids are found within the neutral lipid fractions. The amounts of polyunsaturated fatty acids are 3.4 times higher in blade than stipe. This study highlights the compositional differences between the lipid fractions of stipe and blade from L. hyperborea. The amount of polyunsaturated fatty acids, compared to saturated- and monounsaturated fatty acids, as well as the n-6/n-3-ratio, is known to influence human health. In the pharmaceutical, food, and feed industries this can be of importance for production and sale of different health products. Additionally, lipids are today among the unused by products of alginate production, exploiting this material for commercial interest should give both economical and environmental benefits.

scholarly journals Les lipides des différentes catégories de pépins de Cabernet Sauvignon au moment de la véraison

OENO One ◽  
1980 ◽  
Vol 14 (3) ◽  
pp. 147
Author(s):  
J. J. Lavaud ◽  
Monique Cherrad
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Acid Content ◽  
Neutral Lipids ◽  
Fatty Acid Content ◽  
Polar Lipids ◽  
Cabernet Sauvignon ◽  
Acides Gras ◽  
The Difference

<p style="text-align: justify;">Cinq catégories de pépins de Cabernet Sauvignon ont été séparées à la véraison. Plus de 95 p. 100 des acides gras sont contenus dans les lipides neutres. La différence de composition en acides gras des lipides polaires montre que la localisation des pépins dans une seule loge ou dans deux loges séparées a pour conséquence une modification du fonctionnement des désaturases.</p><p style="text-align: justify;">+++</p><p style="text-align: justify;">Five categories of Cabernet Sauvignon seeds were separated at the beginning of ripening. The neutral lipids contain more than 95 per cent of the fatty acids. The difference in the fatty acid content of polar lipids shows that seeds localized in just one section or in two separate sections results in a modification of the « desaturase » functioning.</p>

scholarly journals Proteomic Analysis of the Function of a Novel Cold-Regulated Multispanning Transmembrane Protein COR413-PM1 in Arabidopsis

2018 ◽  
Vol 19 (9) ◽  
pp. 2572 ◽  
Author(s):  
Chen Su ◽  
Kai Chen ◽  
Qingqian Ding ◽  
Yongying Mou ◽  
Rui Yang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Plasma Membrane ◽  
Fatty Acid ◽  
Proteomic Analysis ◽  
Fatty Acid Biosynthesis ◽  
Transmembrane Protein ◽  
Sugar Metabolism ◽  
Freezing Stress ◽  
Plant Tolerance ◽  
Phosphoribosyl Pyrophosphate

The plasma membrane is the first subcellular organ that senses low temperature, and it includes some spanning transmembrane proteins that play important roles in cold regulation. COR413-PM1 is a novel multispanning transmembrane cold-regulated protein; however, the related functions are not clear in Arabidopsis. We found the tolerance to freezing stress of cor413-pm1 was lower than wild-type (WT). A proteomics method was used to analyze the differentially abundant proteins (DAPs) between cor413-pm1 and WT. A total of 4143 protein groups were identified and 3139 were accurately quantitated. The DAPs associated with COR413-PM1 and freezing treatment were mainly involved in the metabolism of fatty acids, sugars, and purine. Quantitative real-time PCR (qRT-PCR) confirmed the proteomic analysis results of four proteins: fatty acid biosynthesis 1 (FAB1) is involved in fatty acid metabolism and might affect the plasma membrane structure; fructokinase 3 (FRK3) and sucrose phosphate synthase A1 (SPSA1) play roles in sugar metabolism and may influence the ability of osmotic adjustment under freezing stress; and GLN phosphoribosyl pyrophosphate amidotransferase 2 (ASE2) affects freezing tolerance through purine metabolism pathways. In short, our results demonstrate that the multispanning transmembrane protein COR413-PM1 regulates plant tolerance to freezing stress by affecting the metabolism of fatty acids, sugars, and purine in Arabidopsis.

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