In vivo study of the biosynthesis of long-chain fatty acids using deuterated water

1995 ◽  
Vol 269 (2) ◽  
pp. E247-E252 ◽  
Author(s):  
H. O. Ajie ◽  
M. J. Connor ◽  
W. N. Lee ◽  
S. Bassilian ◽  
E. A. Bergner ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
De Novo ◽  
Chain Elongation ◽  
Deuterated Water ◽  
De Novo Synthesis ◽  
Isotopomer Distribution ◽  
Long Chain ◽  
Mass Isotopomer

To determine the contributions of preexisting fatty acid, de novo synthesis, and chain elongation in long-chain fatty acid (LCFA) synthesis, the synthesis of LCFAs, palmitate (16:0), stearate (18:0), arachidate (20:0), behenate (22:0), and lignocerate (24:0), in the epidermis, liver, and spinal cord was determined using deuterated water and mass isotopomer distribution analysis in hairless mice and Sprague-Dawley rats. Animals were given 4% deuterated water for 5 days or 8 wk in their drinking water. Blood was withdrawn at the end of these times for the determination of deuterium enrichment, and the animals were killed to isolate the various tissues for lipid extraction for the determination of the mass isotopomer distributions. The mass isotopomer distributions in LCFA were incompatible with synthesis from a single pool of primer. The synthesis of palmitate, stearate, arachidate, behenate, and lignocerate followed the expected biochemical pathways for the synthesis of LCFAs. On average, three deuterium atoms were incorporated for every addition of an acetyl unit. The isotopomer distribution resulting from chain elongation and de novo synthesis can be described by the linear combination of two binomial distributions. The proportions of preexisting, chain elongation, and de novo-synthesized fatty acids as a percentage of the total fatty acids were determined using multiple linear regression analysis. Fractional synthesis was found to vary, depending on the tissue type and the fatty acid, from 47 to 87%. A substantial fraction (24-40%) of the newly synthesized molecules was derived from chain elongation of unlabeled (recycled) palmitate.

The composition and metabolism of fatty acids in Ips paraconfusus Lanier (Coleoptera: Scolytidae)

1972 ◽  
Vol 50 (10) ◽  
pp. 1263-1267 ◽  
Author(s):  
K. R. Penner ◽  
J. S. Barlow
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Sexual Dimorphism ◽  
Acid Composition ◽  
De Novo ◽  
Monounsaturated Fatty Acids ◽  
Ips Paraconfusus ◽  
Chain Elongation ◽  
De Novo Synthesis

The fatty acid composition of newly emerged Ips paraconfusus Lanier shows no sexual dimorphism and is approximately as follows: C14:0, 0.5%; C16:0, 23.0%; C16:1, 6%; C18:0, 3%; C18:1, 55%; C18:2, 9%; C18:3, 2%. Both sexes, but particularly the female, use up fatty acids, particularly the monounsaturated acids, during reproduction. Isotope from 1-14C-acetate injected into newly emerged females appeared in all saturated and monounsaturated fatty acids within 30 min. There was evidence of de novo synthesis of C14:0 and C16:0, chain elongation of C16:0 to C18:0, and desaturation of C16:0 and C18:0 to yield C16:1 and C18:1 respectively.

scholarly journals A Review of the Metabolic Origins of Milk Fatty Acids

2013 ◽  
Vol 5 (3) ◽  
pp. 270-274 ◽  
Author(s):  
Anamaria COZMA ◽  
Doina MIERE ◽  
Lorena FILIP ◽  
Sanda ANDREI ◽  
Roxana BANC ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Mammary Gland ◽  
Fatty Acid ◽  
Milk Fat ◽  
De Novo ◽  
Long Chain Fatty Acids ◽  
De Novo Synthesis ◽  
Ruminal Biohydrogenation ◽  
Long Chain ◽  
Chain Fatty Acids

Milk fat and its fatty acid profile are important determinants of the technological, sensorial, and nutritional properties of milk and dairy products. The two major processes contributing to the presence of fatty acids in ruminant milk are the mammary lipogenesis and the lipid metabolism in the rumen. Among fatty acids, 4:0 to 12:0, almost all 14:0 and about a half of 16:0 in milk fat derive from de novo synthesis within the mammary gland. De novo synthesis utilizes as precursors acetate and butyrate produced through carbohydrates ruminal fermentation and involves acetyl-CoA carboxylase and fatty acid synthetase as key enzymes. The rest of 16:0 and all of the long-chain fatty acids derive from mammary uptake of circulating lipoproteins and nonesterified fatty acids that originate from digestive absorption of lipids and body fat mobilization. Further, long-chain fatty acids as well as medium-chain fatty acids entering the mammary gland can be desaturated via Δ-9 desaturase, an enzyme that acts by adding a cis-9-double bond on the fatty acid chain. Moreover, ruminal biohydrogenation of dietary unsaturated fatty acids results in the formation of numerous fatty acids available for incorporation into milk fat. Ruminal biohydrogenation is performed by rumen microbial population as a means of protection against the toxic effects of polyunsaturated fatty acids. Within the rumen microorganisms, bacteria are principally responsible for ruminal biohydrogenation when compared to protozoa and anaerobic fungi.

scholarly journals Metabolism of saturated and polyunsaturated very-long-chain fatty acids in fibroblasts from patients with defects in peroxisomal β-oxidation

1990 ◽  
Vol 269 (3) ◽  
pp. 671-677 ◽  
Author(s):  
J M Street ◽  
H Singh ◽  
A Poulos
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
De Novo ◽  
Normal Skin ◽  
Carbon Chain ◽  
Water Soluble ◽  
Chain Elongation ◽  
Long Chain Fatty Acids ◽  
Long Chain ◽  
Chain Fatty Acids

The metabolism of [1-14C]lignoceric acid (C24:0) and [1-14C]tetracosatetraenoic acid (C24:4, n-6) was studied in normal skin fibroblast cultures and in cultures from patients with defects in peroxisomal β-oxidation (but normal peroxisomal numbers). Cells from X-linked adrenoleukodystrophy (ALD) patients with a presumed defect in a peroxisomal acyl-CoA synthetase, specific for fatty acids of carbon chain lengths greater than 22 (very-long-chain fatty acids; VLCFA), showed a relatively normal production of radiolabelled CO2 and water-soluble metabolites from [1-14C]C24:0. However, the products of synthesis from acetate de novo (released by β-oxidation), i.e. C16 and C18 fatty acids, were decreased, and carbon chain elongation of the fatty acid was increased. In contrast, cell lines from two patients with an unidentified lesion in peroxisomal β-oxidation (peroxisomal disease, PD) showed a marked deficiency in CO2 and water-soluble metabolite production, a decreased synthesis of C16 and C18 fatty acids and an increase in carbon chain elongation. The relatively normal β-oxidation activity of ALD cells appears to be related to low uptake of substrate, as a defect in β-oxidation is apparent when measurements are performed on cell suspensions under high uptake conditions. Oxidation of [1-14C]C24:4 was relatively normal in ALD cells and in the cells from one PD patient but abnormal in those from the other. Our data suggest that, despite the deficiency in VLCFA CoA synthetase, ALD cells retain a near normal ability to oxidize both saturated and polyunsaturated VLCFA under some culture conditions. However, acetate released by β-oxidation of the saturated VLCFA and, to a much lesser degree, the polyunsaturated VLCFA, appears to be used preferentially for the production of CO2 and water-soluble products, and acetate availability for fatty acid synthesis in other subcellular compartments is markedly decreased. It is likely that the increased carbon chain elongation of the saturated VLCFA which is also observed reflects the increased availability of substrate (C24:0) and/or an increase in microsomal elongation activity in ALD cells.

Lipid composition of developing Xenopus laevis embryos

1976 ◽  
Vol 54 (6) ◽  
pp. 578-582 ◽  
Author(s):  
Mary Mes-Hartree ◽  
John B. Armstrong
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Xenopus Laevis ◽  
Lipid Content ◽  
Lipid Composition ◽  
De Novo ◽  
Total Lipid Content ◽  
De Novo Synthesis ◽  
Xenopus Laevis Embryos

The total lipid content, amount of phospholipid, proportions of major polar and neutral lipid classes, and the overall fatty acid composition were examined in Xenopus laevis embryos. No obvious differences were observed in any of the parameters between fertilization and hatching, or between eggs produced by different females. The average lipid content per egg was 113 μg, 31.6 μg of which was phospholipid. The major phospholipids were phosphatidylcholine and sphingomyelin. The major fatty acids were palmitic and oleic acids, but polyunsaturated fatty acids were also present in substantial amounts. The results suggest that significant de novo synthesis of lipids does not occur until after hatching.

Fatty Acids: Evolution in Relation to Neurobiology

1993 ◽  
Vol 71 (9) ◽  
pp. 683-683 ◽  
Author(s):  
M. T. Clandinin
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Acid Content ◽  
Essential Fatty Acids ◽  
Fatty Acid Content ◽  
Chain Elongation ◽  
Brain Membrane ◽  
The Impact ◽  
Long Chain

Metabolism of long-chain polyunsaturated fatty acids derived from 18:2ω−6 and 18:3ω−3 by chain elongation – desaturation is essential for synthesis of complex structural lipids, leukotrienes, thromboxanes, and prostaglandins. These essential fatty acids are required for normal function in developing tissues and appropriate maturation of a wide variety of physiological processes. During development, fetal accretion of long-chain metabolites of ω−6 and ω−3 fatty acids may result from maternal or placental synthesis and transfer or, alternatively, from the metabolism of 18:2ω−6 and 18:3ω−3 to longer chain homologues by the fetus. After birth the infant must synthesize or be fed the very long chain polyunsaturated fatty acids of C20 and C22 type derived from 18:2ω−6 and 18:3ω−3.Metabolism of ω−6 and ω−3 fatty acids utilizes the same enzyme system and is competitive. When levels of dietary ω−3 and ω−6 C18 fatty acids are altered, the levels of metabolites of these precursor fatty acids change in specific brain membranes, influencing membrane lipid dependent functions. For example, a diet unbalanced in very long chain ω−3 and ω−6 fatty acids may increase brain membrane ω−3 fatty acid content when 20:5ω−3 is fed, while decreasing membrane fatty acid content of the ω−6 series of competing fatty acids. As 20:4ω−6 is quantitatively and qualitatively important to brain phospholipid, significant reduction in brain levels of 20:4ω−6 may be less than optimal. The impact of these compositional changes on brain function is not yet clear.The authors in this symposium address how this general area of essential fatty acid metabolism is relevant to the evolution of man, growth and development of fish, function of the retina and neural tissue, cognitive development of infants, and infant nutrition.

scholarly journals Inhibition of Very-Long-Chain Fatty Acid Formation by Indanofan, 2-[2-(3-Chlorophenyl)oxiran-2-ylmethyl]-2-ethylindan-1,3-dione, and Its Relatives

2002 ◽  
Vol 57 (1-2) ◽  
pp. 72-74 ◽  
Author(s):  
Hideomi Takahashi ◽  
Jochen Schmalfuß ◽  
Aiko Ohki ◽  
Akemi Hosokawa ◽  
Akira Tanaka ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
De Novo ◽  
Allium Porrum ◽  
Inhibitory Effects ◽  
Strong Activity ◽  
Oxirane Group ◽  
Malonyl Coa ◽  
High Concentrations ◽  
Long Chain

Indanofan and its analogs inhibited the elongation of stearoyl- or arachidoyl-CoA by [2-14C]-malonyl-CoA in leek microsomes from Allium porrum. Although the precise mode of interaction of indanofan at the molecular level is not completely clarified by the present study, it is concluded that indanofan and analogs act as inhibitor of the elongase enzyme involved in de novo biosynthesis of fatty acids with an alkyl chain longer than C18, called very-long-chain fatty acids (VLCFAs). For a strong inhibition of VLCFA formation chloro substituents at the benzene ring and the oxirane group were necessary. Furthermore, the greenhouse test showed strong activity for indanofan and its analogs, and the scores coincided with cell-free elongation inhibition. The cell-free assay, however, failed to indicate any activity for an analog having a methylene instead of the oxirane group, while both Digitaria ciliaris and Echinochloa oryzicola were killed with 1 kg a.i./ha. This finding cannot be discussed because the applied use rate of 1 kg a.i./ha is too high to allow for a score differentiation. For high concentrations of this compound additional unknown inhibitory effects may be involved besides fatty acid elongation.

On the purification of a fatty acid synthetase complex from an insect

1976 ◽  
Vol 54 (8) ◽  
pp. 1397-1399 ◽  
Author(s):  
S. N. Thompson ◽  
J. S. Barlow
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Column Chromatography ◽  
De Novo ◽  
Gel Filtration ◽  
Fatty Acid Synthetase ◽  
De Novo Synthesis ◽  
Anion Exchange Column ◽  
Malonyl Coa ◽  
Salt Fractionation

The fatty acid synthetase complex of the blowfly, Lucilia sericata, catalyzing the de novo synthesis of fatty acids from acetyl- and malonyl-CoA (EC 2.3.1.9 and EC 2.3.1.39 respectively) and requiring NADPH, was isolated from whole-insect homogenates by ultracentrifugation. Purification was carried out by salt fractionation, anion exchange column chromatography on ECTEOLA (epichlorohydrin triethanolamine) cellulose, and gel filtration column chromatography on Sephadex®.

scholarly journals Long-Chain Saturated Fatty Acids, Palmitic and Stearic Acids, Enhance the Repair of Photosystem II

2020 ◽  
Vol 21 (20) ◽  
pp. 7509
Author(s):  
Haruhiko Jimbo ◽  
Kensuke Takagi ◽  
Takashi Hirashima ◽  
Yoshitaka Nishiyama ◽  
Hajime Wada
Keyword(s):  
Fatty Acids ◽  
Photosystem Ii ◽  
Chemical Potential ◽  
De Novo ◽  
Genetic Manipulation ◽  
Saturated Fatty Acids ◽  
De Novo Synthesis ◽  
Strong Light ◽  
Long Chain ◽  
Synechocystis Sp

Free fatty acids (FFA) generated in cyanobacterial cells can be utilized for the biodiesel that is required for our sustainable future. The combination of FFA and strong light induces severe photoinhibition of photosystem II (PSII), which suppresses the production of FFA in cyanobacterial cells. In the present study, we examined the effects of exogenously added FFA on the photoinhibition of PSII in Synechocystis sp. PCC 6803. The addition of lauric acid (12:0) to cells accelerated the photoinhibition of PSII by inhibiting the repair of PSII and the de novo synthesis of D1. α-Linolenic acid (18:3) affected both the repair of and photodamage to PSII. Surprisingly, palmitic (16:0) and stearic acids (18:0) enhanced the repair of PSII by accelerating the de novo synthesis of D1 with the mitigation of the photoinhibition of PSII. Our results show chemical potential of FFA in the regulation of PSII without genetic manipulation.

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