scholarly journals Identification of Polyunsaturated Fatty Acids Synthesis Pathways in the Toxic Dinophyte Alexandrium minutum Using 13C-Labelling

Biomolecules ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1428
Author(s):  
Marine Remize ◽  
Frédéric Planchon ◽  
Ai Ning Loh ◽  
Fabienne Le Grand ◽  
Christophe Lambert ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Polyketide Synthase ◽  
Neutral Lipids ◽  
Acid Synthesis ◽  
Exponential Growth Phase ◽  
Lag Phase ◽  
Alexandrium Minutum ◽  
The One

The synthetic pathways responsible for the production of the polyunsaturated fatty acids 22:6n-3 and 20:5n-3 were studied in the Dinophyte Alexandrium minutum. The purpose of this work was to follow the progressive incorporation of an isotopic label (13CO2) into 11 fatty acids to better understand the fatty acid synthesis pathways in A. minutum. The Dinophyte growth was monitored for 54 h using high-frequency sampling. A. minutum presented a growth in two phases. A lag phase was observed during the first 30 h of development and had been associated with the probable temporary encystment of Dinophyte cells. An exponential growth phase was then observed after t30. A. minutum rapidly incorporated 13C into 22:6n-3, which ended up being the most 13C-enriched polyunsaturated fatty acid (PUFA) in this experiment, with a higher 13C atomic enrichment than 18:4n-3, 18:5n-3, 20:5n-3, and 22:5n-3. Overall, the 13C atomic enrichment (AE) was inversely proportional to number of carbons in n-3 PUFA. C18 PUFAs, 18:4n-3, and 18:5n-3, were indeed among the least 13C-enriched FAs during this experiment. They were assumed to be produced by the n-3 PUFA pathway. However, they could not be further elongated or desaturated to produce n-3 C20-C22 PUFA, because the AEs of the n-3 C18 PUFAs were lower than those of the n-3 C20-C22 PUFAs. Thus, the especially high atomic enrichment of 22:6n-3 (55.8% and 54.9% in neutral lipids (NLs) and polar lipids (PLs), respectively) led us to hypothesize that this major PUFA was synthesized by an O2-independent Polyketide Synthase (PKS) pathway. Another parallel PKS, independent of the one leading to 22:6n-3, was also supposed to produce 20:5n-3. The inverse order of the 13C atomic enrichment for n-3 PUFAs was also suspected to be related to the possible β-oxidation of long-chain n-3 PUFAs occurring during A. minutum encystment.

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.

Fatty Acid Composition of Early Non-Feeding Larvae of the European Flat Oyster, Ostrea Edulis

1991 ◽  
Vol 71 (3) ◽  
pp. 691-705 ◽  
Author(s):  
M. M. Helm ◽  
D. L. Holland ◽  
S. D. Utting ◽  
J. East
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Acid Composition ◽  
Wild Population ◽  
Neutral Lipids ◽  
Ostrea Edulis ◽  
Pufa Content ◽  
Flat Oyster

A total of 113 broods of Ostrea edulis L. larvae from a closely-controlled hatchery conditioning regime, from specific broodstock treatments, and from brooding oysters taken from a wild population in Poole Harbour, was analysed for fatty acid composition. Major differences in polyunsaturated fatty acids (PUFAs) were detected as the year proceeded, with increased levels of 20:5 (n-3) and 22:6 (n-3) from late June. Significant decreases in the PUFA content of both phospholipids and neutral lipids accompanied development from fertilized eggs to immediately pre-liberation larvae, but there was some evidence that the 20:4 (n-6) and 22:6 (n-3) content of phospholipids was protected. Fatty acid composition and content of newly liberated larvae were influenced by conditions during broodstock fattening and early gametogenesis (phospholipids) and by conditions during the later stages of oocyte development (neutral lipids).

scholarly journals Metabolism of phospholipids and the characterization of fatty acids in bovine corpus luteum

1968 ◽  
Vol 108 (2) ◽  
pp. 317-323 ◽  
Author(s):  
T. W. Scott ◽  
W. Hansel ◽  
L. E. Donaldson
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Neutral Lipids ◽  
Total Phospholipid ◽  
Lipid Fraction ◽  
Specific Radioactivity ◽  
Lactate Production ◽  
Corpora Lutea ◽  
Luteal Tissue

1. Phosphatidylcholine was the predominant phospholipid in bovine corpora lutea; it accounted for about 50% of the total phospholipid phosphorus. Phosphatidylethanolamine (13%) and ethanolamine plasmalogen (8–9%) were the next two major components. 2. After incubation of the tissue with [32P]orthophosphate the total radioactivity and specific radioactivity of phosphatidylinositol were higher than those of any other lipid. 3. Luteinizing hormone failed to increase significantly the incorporation of [32P]orthophosphate into total phospholipids from luteal tissue slices, but did stimulate progesterone synthesis and lactate production. 4. The proportion of oleate (18:1) in the neutral lipids and phospholipids was higher than that of any other fatty acid. 5. The proportion of unsaturated fatty acid in the tissue lipids exceeded 60%, and almost half of this was polyunsaturated. Arachidonate (20:4), docosatetraenoate (22:4) and docosapentaenoate (22:5) were the principal polyunsaturated fatty acids. 6. After incubation of luteal tissue with [1−14C]acetate, the greatest proportion of radioactivity in the fatty acids isolated from the total lipid fraction was in palmitate (16:0) and docosatetraenoate (22:4). Polyunsaturated fatty acids accounted for almost 50% of the 14C radioactivity incorporated and this pattern was observed in phospholipids, triglycerides and free fatty acids.

scholarly journals Fatty Acid Profiles of Stipe and Blade from the Norwegian Brown Macroalgae Laminaria hyperborea with Special Reference to Acyl Glycerides, Polar Lipids, and Free Fatty Acids

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Lena Foseid ◽  
Hanne Devle ◽  
Yngve Stenstrøm ◽  
Carl Fredrik Naess-Andresen ◽  
Dag Ekeberg
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Free Fatty Acids ◽  
Neutral Lipids ◽  
Dry Weight ◽  
Polar Lipids ◽  
Fatty Acid Profiles ◽  
Laminaria Hyperborea ◽  
Lipid Fractions

A thorough analysis of the fatty acid profiles of stipe and blade from the kelp species Laminaria hyperborea is presented. Lipid extracts were fractionated into neutral lipids, free fatty acids, and polar lipids, prior to derivatization and 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. The fatty acid amounts are higher in blade than in stipe (7.42 mg/g dry weight and 2.57 mg/g dry weight, resp.). The highest amounts of n-3 fatty acids are found within the neutral lipid fractions with 590.6 ug/g dry weight and 100.9 ug/g dry weight for blade and stipe, respectively. The amounts of polyunsaturated fatty acids are 3.4 times higher in blade than stipe. The blade had the highest PUFA/SFA ratio compared to stipe (1.02 versus 0.76) and the lowest n-6/n-3 ratio (0.8 versus 3.5). 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 is known to influence human health. In the pharmaceutical, food, and feed industries, this can be of importance for production of different health products.

scholarly journals Genetic regulation of the bacterial omega-3 polyunsaturated fatty acid biosynthesis pathway

2020 ◽  
Author(s):  
Marco N. Allemann ◽  
Eric E. Allen
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Fatty Acid Synthesis ◽  
Fatty Acid Synthase ◽  
Genetic Regulation ◽  
Transcriptional Regulator ◽  
Acid Synthesis ◽  
Biosynthesis Pathway ◽  
Omega 3

AbstractA characteristic among many marine Gammaproteobacteria is the biosynthesis and incorporation of omega-3 polyunsaturated fatty acids into membrane phospholipids. Biosynthesis of eicosapentaenoic (EPA) and/or docosahexaenoic (DHA) acids is accomplished using a polyketide/fatty acid synthase mechanism encoded by a set of five genes pfaABCDE. This unique fatty acid synthesis (FAS) pathway co-exists with the canonical Type II dissociated fatty acid synthesis pathway, which is responsible for the biosynthesis of saturated, monounsaturated, and hydroxylated fatty acids used in phospholipid and lipid A biosynthesis. In this work, a genetic approach was undertaken to elucidate genetic regulation of the pfa genes in the model marine bacterium Photobacterium profundum SS9. Using a reporter gene fusion, we showed that expression of the pfa operon is down regulated in response to exogenous fatty acids, particularly long chain monounsaturated fatty acids. This regulation occurs independently of the canonical fatty acid regulators, FabR and FadR, present in P. profundum SS9. Transposon mutagenesis and screening of a library of mutants identified a novel transcriptional regulator, which we have designated pfaF, to be responsible for the observed regulation of the pfa operon in P. profundum SS9. Gel mobility shift and DNase I footprinting assays confirmed that PfaF binds the pfaA promoter and identified the PfaF binding site.ImportanceThe production of polyunsaturated fatty acids (PUFA) by marine Gammaproteobacteria, particularly those from deep-sea environments, has been known for decades. These unique fatty acids are produced by a polyketide-type mechanism and subsequently incorporated into the phospholipid membrane. While much research has focused on the biosynthesis genes, their products and the phylogenetic distribution of these gene clusters, no prior studies have detailed the genetic regulation of this pathway. This study describes how this pathway is regulated under various culture conditions and has identified and characterized a fatty acid responsive transcriptional regulator specific to the PUFA biosynthesis pathway.

Energy balances of beef tallow and soyabean oil in broiler chickens

2007 ◽  
Vol 2007 ◽  
pp. 240-240
Author(s):  
Sasiphan Wongsuthavas ◽  
Chalermpol Yuangklang ◽  
Jamlong Mitchaothai ◽  
Kraisit Vasupen ◽  
Anton Beynen
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Body Fat ◽  
Fatty Acid Synthesis ◽  
Beef Tallow ◽  
Broiler Chickens ◽  
Saturated Fatty Acids ◽  
Acid Synthesis ◽  
Abdominal Fat

From previous reports indicate that broiler chickens fed diets enriched with polyunsaturated fatty acids have less abdominal fat or total body fat (Sanz et al., 1999) deposition than do broiler chickens fed diets containing saturated fatty acids. In general, body fat accumulation may be considered the net result of the balance among dietary absorbed fat, endogenous fat synthesis (lipogenesis) and fat catabolism via β-oxidation (lypolysis). Thus, if the amount of absorbed fat is the same, lower body fat deposition may be attributed to increased fat catabolism or diminished endogenous fatty acid synthesis or to both process. Differences in lipid oxidation rates seem to be the main mechanism involved in this effect. Supplementation of unsaturated fatty acids in diets can be enhanced fat catabolism and reduced fatty acid synthesis were reported to occur in rats fed polyunsaturated fatty acid rich in diets compared with rats fed diets enriched with saturated fatty acids (Crespo and Esteve-Garcia, 2002). Polyunsaturated fatty acids rich in diet effect on fat absorption were increased. In, contrast amount of abdominal fat deposition was decreased. It may be that the polyunsaturated fatty acid was higher rate fat oxidation or lower rate of fatty acid synthesis or both. The present study was undertaken to determine the effect of amount of beef tallow versus soybean oil absorbed is the same on energy intake, energy excretion, energy retention and energy expenditure of broiler chickens.

Fatty acid characteristics in two symbiont-bearing mussels from deep-sea hydrothermal vents of the south-western Pacific

1997 ◽  
Vol 77 (2) ◽  
pp. 473-492 ◽  
Author(s):  
Vincent Pranal ◽  
Aline Fiala-Medioni ◽  
Jean Guezennec
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Deep Sea ◽  
Hydrothermal Vents ◽  
Neutral Lipids ◽  
Physiological State ◽  
Phospholipid Fatty Acids ◽  
Gas Liquid Chromatography ◽  
High Level

Two bacteria-bearing mussels,Bathymodiolus breviorandB. elongatus, collected at five deep-sea hydrothermal sites from Lau and Fiji back arc basins (south-west Pacific), were analysed for polar and neutral lipids using gas-liquid chromatography mass spectroscopy (GLC-MS). The respective fatty acid distributions found in gills and mantles were compared to data from a Mediterranean littoral filter-feeding mussel,Mytilus galloprovincialis. The main characteristic common to the gills of the two vent mussels was the high level of (n-7) monounsaturated phospholipid fatty acids, which are supposed to originate from sulphur-oxidizing symbionts. Using palmitoleic, 16:1 (n-7), and vaccenic, 18:1 (n-7), phospholipid fatty acids as bacterial markers, endobacterial biomass was estimated to account for 2–10% of the vent mussel gill volume. Vent mussel tissues were poor in plant-derived polyunsaturated fatty acids, indicating the limited importance of the photosynthesis based material in the metabolism of these hydrothermal vent bivalves. It is suggested that some compounds, such as nonmethylene-interrupted dienoic fatty acids and specific trienoic fatty acids originating from elongation and desaturation of oleic and palmitoleic acids, respectively, were synthesized in order to substitute exogenous plant-derived polyunsaturated fatty acids considered as essential in marine invertebrates. The high level of neutral lipids in vent mussel gills suggests that these compounds are used as a major energy storage material. The neutral lipid/phospholipid ratio in gills emphasized the preponderance of the endosymbionts in vent mussel nutrition. Using this ratio as an index of the physiological state, the symbiosis patterns in different hydrothermal fields were compared.

scholarly journals Stimulation of fatty acid synthesis in vitro by gonadotrophin-induced testicular ribonucleic acid

1968 ◽  
Vol 108 (1) ◽  
pp. 147-152 ◽  
Author(s):  
Ajit Goswami ◽  
James K. Skipper ◽  
William L. Williams
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Luteinizing Hormone ◽  
Polyunsaturated Fatty Acids ◽  
Fatty Acid Synthesis ◽  
Follicle Stimulating Hormone ◽  
Acid Synthesis ◽  
Stimulation Of ◽  
Stimulating Hormone

RNA from testes of hypophysectomized rats treated with follicle-stimulating hormone and luteinizing hormone markedly stimulates in vitro the incorporation of acetate and malonate (as CoA derivatives) into polyunsaturated fatty acids. The system in vitro contains the components necessary for both protein and fatty acid synthesis. That the RNA is a hormone-induced messenger type that causes enzyme synthesis that then causes fatty acid synthesis is supported by the following observations: (1) the stimulation of RNA synthesis by follicle-stimulating hormone and luteinizing hormone is decreased by injection of the animals with actinomycin D; (2) puromycin in the system in vitro decreases the synthesis of polyunsaturated fatty acids; (3) the activity of the RNA preparation is destroyed by digestion with ribonuclease; in fact, the digest is inhibitory, which is a characteristic of messenger-RNA-mediated protein synthesis; (4) protein that might be denatured enzyme is virtually absent from the effective RNA preparations.

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