scholarly journals A non-canonical Δ9-desaturase synthesizing palmitoleic acid identified in the thraustochytrid Aurantiochytrium sp. T66

2021 ◽  
Author(s):  
E-Ming Rau ◽  
Inga Marie Aasen ◽  
Helga Ertesvåg
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Palmitoleic Acid ◽  
Unsaturated Fatty Acids ◽  
Gene Annotation ◽  
Vaccenic Acid ◽  
Strain Engineering ◽  
Δ9 Desaturase ◽  
Δ12 Desaturase

Abstract Thraustochytrids are oleaginous marine eukaryotic microbes currently used to produce the essential omega-3 fatty acid docosahexaenoic acid (DHA, C22:6 n-3). To improve the production of this essential fatty acid by strain engineering, it is important to deeply understand how thraustochytrids synthesize fatty acids. While DHA is synthesized by a dedicated enzyme complex, other fatty acids are probably synthesized by the fatty acid synthase, followed by desaturases and elongases. Which unsaturated fatty acids are produced differs between different thraustochytrid genera and species; for example, Aurantiochytrium sp. T66, but not Aurantiochytrium limacinum SR21, synthesizes palmitoleic acid (C16:1 n-7) and vaccenic acid (C18:1 n-7). How strain T66 can produce these fatty acids has not been known, because BLAST analyses suggest that strain T66 does not encode any Δ9-desaturase-like enzyme. However, it does encode one Δ12-desaturase-like enzyme. In this study, the latter enzyme was expressed in A. limacinum SR21, and both C16:1 n-7 and C18:1 n-7 could be detected in the transgenic cells. Our results show that this desaturase, annotated T66Des9, is a Δ9-desaturase accepting C16:0 as a substrate. Phylogenetic studies indicate that the corresponding gene probably has evolved from a Δ12-desaturase-encoding gene. This possibility has not been reported earlier and is important to consider when one tries to deduce the potential a given organism has for producing unsaturated fatty acids based on its genome sequence alone. Key points • In thraustochytrids, automatic gene annotation does not always explain the fatty acids produced. • T66Des9 is shown to synthesize palmitoleic acid (C16:1 n-7). • T66des9 has probably evolved from Δ12-desaturase-encoding genes.

scholarly journals A kinetic rationale for functional redundancy in fatty acid biosynthesis

2020 ◽  
Vol 117 (38) ◽  
pp. 23557-23564
Author(s):  
Alex Ruppe ◽  
Kathryn Mains ◽  
Jerome M. Fox
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Unsaturated Fatty Acids ◽  
Fatty Acid Biosynthesis ◽  
Average Length ◽  
Functional Redundancy ◽  
Experimental Investigations ◽  
Total Production

Cells build fatty acids with biocatalytic assembly lines in which a subset of enzymes often exhibit overlapping activities (e.g., two enzymes catalyze one or more identical reactions). Although the discrete enzymes that make up fatty acid pathways are well characterized, the importance of catalytic overlap between them is poorly understood. We developed a detailed kinetic model of the fatty acid synthase (FAS) ofEscherichia coliand paired that model with a fully reconstituted in vitro system to examine the capabilities afforded by functional redundancy in fatty acid synthesis. The model captures—and helps explain—the effects of experimental perturbations to FAS systems and provides a powerful tool for guiding experimental investigations of fatty acid assembly. Compositional analyses carried out in silico and in vitro indicate that FASs with multiple partially redundant enzymes enable tighter (i.e., more independent and/or broader range) control of distinct biochemical objectives—the total production, unsaturated fraction, and average length of fatty acids—than FASs with only a single multifunctional version of each enzyme (i.e., one enzyme with the catalytic capabilities of two partially redundant enzymes). Maximal production of unsaturated fatty acids, for example, requires a second dehydratase that is not essential for their synthesis. This work provides a kinetic, control-theoretic rationale for the inclusion of partially redundant enzymes in fatty acid pathways and supplies a valuable framework for carrying out detailed studies of FAS kinetics.

scholarly journals The polymorphisms of genes associated with the profile of fatty acids of sheep

2019 ◽  
Vol 71 (1) ◽  
pp. 303-313 ◽  
Author(s):  
C. Esteves ◽  
K.G. Livramento ◽  
L.V. Paiva ◽  
A.P. Peconick ◽  
I.F.F. Garcia ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Single Strand Conformation Polymorphism ◽  
Diacylglycerol Acyltransferase ◽  
Genetic Groups ◽  
Δ9 Desaturase ◽  
Atherogenicity Index ◽  
Stearoyl Coa Desaturase ◽  
Conformation Polymorphism

ABSTRACT The present study aimed to evaluate the occurrence of polymorphisms in Diacylglycerol acyltransferase (DGTA-1 and 2), Fatty acid synthase (FASN), Stearoyl-CoA desaturase (SCD) genes and the Thioesterase domain of FASN (TE-FASN) gene that may be related to the lipid profile. In the experiment, a total of 84 sheep from different genetic groups were used. For the evaluation of the polymorphism of the genes, PCR-Single Strand Conformation Polymorphism (SSCP) technique and subsequent sequencing were used. In DGAT-2 gene, four genotypes were identified with the presence of 6 polymorphisms, with two (c.229T> C; c.255T> C) that resulted into the exchange of phenylalanine by leucine. In FASN gene, two genotypes were identified. In TE-FASN gene, three genotypes and 17 polymorphisms were identified. DGAT-1 and SCD genes did not reveal the occurrence of polymorphism. There was difference in relation to C14: 0, C18: 0 fatty acids and Δ9-desaturase C18 for DGAT-2 gene and of C18: 2ω6t for TE-FASN. There were differences among the genetic groups for C10: 0, C12: 0, C17: 0, C18: 2ω6t, C18: 3ω3, C20: 2, total of ω3, ω3/ω6 and atherogenicity index. There is occurrence of polymorphism of DGAT-2 and TE-FASN genes and these should be further studied in sheep since they revealed influence of the genotypes on the fatty acid profile.

Effect of different forms of polyunsaturated fatty acids on duodenal and serum fatty acid profiles in sheep

1994 ◽  
Vol 74 (4) ◽  
pp. 595-600 ◽  
Author(s):  
F. Enjalbert ◽  
M. C. Nicot ◽  
D. Griess ◽  
M. Vernay ◽  
R. Moncoulon
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Vaccenic Acid ◽  
Soy Oil ◽  
Ruminal Fermentation ◽  
Serum Fatty Acid ◽  
Calcium Salts ◽  
Physical Form ◽  
Ruminal Biohydrogenation

Four sheep cannulated in the rumen and proximal duodenum were used in a 4 × 4 cross-over design to investigate the effects of ruminal fatty acid (FA) infusion on duodenal and serum FA profiles. The diets were composed of 85.7% natural grassland hay and 8.6% concentrate supplemented with 5.7% soy oil for diet SO, 5.7% emulsified soy oil for diet ESO, 6.7% calcium salts of soy or palm FA for diets CaSSO and CaSP, respectively. Diets were formulated to be isonitrogenous and isoenergetic; total FA content in dry matter was 6.4–6.6%. Characteristics of ruminal fermentation were not affected by source or physical form of FA. The proportion of stearic acid in the duodenal flow (% of the total C18) was high compared with total diet, e.g., 49.8 vs. 3.5 and 54.3 vs. 9.4% for soy and palm diets, respectively. Ruminal biohydrogenation and unsaturated FA was lower for CaS diets than for SO and ESO diets (48.7 and 60.9 vs. 81.2 and 94.7%, for oleic and linoleic acids, respectively). As a result, trans-vaccenic acid levels in duodenal flow and serum (% or total FA) were lower for the CaS diets than for SO and ESO diets (8.3 vs. 36.0% and 0.9 vs. 7.8%, respectively). Unsaturated FA as CaS were partly protected against ruminal biohydrogenation, and can be effective in increasing intestinal absorption of unsaturated FA. Key words: Unsaturated fatty acids, soy oil, calcium salts, biohydrogenation, sheep

scholarly journals Identification and Analysis of the FAD Gene Family in Walnuts (Juglans regia L.) Based on Transcriptome Data

2020 ◽  
Author(s):  
Kai Liu ◽  
Shugang Zhao ◽  
Shuang Wang ◽  
Hongxia Wang ◽  
Zhihua Zhang
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Gene Family ◽  
Linolenic Acid ◽  
Unsaturated Fatty Acids ◽  
Acid Synthesis ◽  
Main Function ◽  
Genome Database ◽  
Homologous Genes ◽  
Δ9 Desaturase

Abstract Background: Walnut kernels contain a large amount of unsaturated fatty acids, such as linoleic acid and linolenic acid, which are essential fatty acids for humans and have important effects on growth and health. The main function of fatty acid desaturase (FAD), which is widely distributed in organisms, is to remove hydrogen from carbon chains in the biosynthesis of unsaturated fatty acids to generate C=C bonds. Results: By performing a series of bioinformatics analysis, 24 members of the JrFAD gene family were identified from the genome database of walnut, and then compared with the homologous genes from Arabidopsis. Phylogenetic analysis showed that JrFADs were classified into four subfamilies: the SAD desaturase subfamily, Δ7/Δ9 desaturase subfamily, Δ12/ω-3 desaturase subfamily and "front-end" desaturase subfamily. Meanwhile, the expression of fatty acid synthesis genes in walnut kernels at different developmental stages was analysed by transcriptome sequencing, with expression of JrFAD3-1, which encodes an enzyme involved in linolenic acid synthesis, being particularly prominent. The relative expression level of JrFAD3-1 changed dramatically with the kernel development stages and exhibited a Bell-Shaped Curve. A significant positive correlation was observed between the expression of JrFAD3-1 during 70-100 DAF (Days after flowering) and the content of alpha-linolenic acid during 100-130 DAF, with a correlation coefficient of 0.991. Additionally, JrFAD3-1 was proved closely related to homologous genes in Betula pendula and Corylus heterophylla, indicating that the conserved structure of FADs is consistent with classical plant taxonomy. Conclusion: Twenty-four members JrFADs in walnut were identified and classified into four subfamilies. JrFAD3-1 may play significant roles in the biosynthesis of polyunsaturated fatty acids in walnut.

scholarly journals Meat lipid profile of steers finished in pearl millet pasture with different rates of concentrate

2013 ◽  
Vol 48 (5) ◽  
pp. 553-558 ◽  
Author(s):  
Luis Fernando Glasenapp de Menezes ◽  
Luciane Rumpel Segabinazzi ◽  
João Restle ◽  
Leandro da Silva Freitas ◽  
Ivan Luiz Brondani ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Lipid Profile ◽  
Pearl Millet ◽  
Unsaturated Fatty Acids ◽  
Vaccenic Acid ◽  
Live Weight ◽  
Beef Steers ◽  
Omega 3 ◽  
Omega 6

The objective of this work was to evaluate the meat lipid profile from Devon beef steers finished in pearl millet (Pennisetum americanum) pasture and fed at different rates of concentrate supplementary diet. Twelve steers weighing 270 kg, at 12‑month‑average initial age, were randomly distributed into three treatments: pearl millet pasture; and pearl millet pasture plus a concentrate equivalent at 0.5 or 1.0% of body weight, with two replicates. Total contents of saturated and unsaturated fatty acids, the polyunsaturated:saturated ratio and other relevant fatty acids as the vaccenic acid, conjugated linoleic acid, omega‑3, and omega‑6 were not affected by the consumption of a concentrate supplement at 0.5 or 1.0% live weight. However, the 0.5% supplementation level reduced the concentration of dihomo‑γ‑linolenic fatty acid (C20: 3 n‑6), while the 1.0% supplementation level elevated the content of docosahexaenoic (DHA) (C22: 6 n‑3) fatty acid, and the omega‑6:omega‑3 ratio in meat. Consumption of up to 1.0% energy supplementation increases the omega‑6:omega‑3 ratio in meat from Devon steers grazing on pearl millet pasture.

scholarly journals Analysis Fatty Acids Profile in Tabanus bivittatus Mats with Gas Chromatography-Mass Spectrometry

2015 ◽  
Vol 9 (1) ◽  
pp. 113-118
Author(s):  
Wang Yanhua ◽  
Wu Fuhua ◽  
Guo Zhaohan ◽  
Peng Mingxing ◽  
Xia Min ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Palmitoleic Acid ◽  
Unsaturated Fatty Acids ◽  
Methyl Esters ◽  
Soxhlet Extraction ◽  
Gas Chromatography Mass Spectrometry ◽  
Chemical Components ◽  
Fatty Acids Profile ◽  
Total Fatty Acids

Tabanus bivittatus Mats., a traditional Chinese medicine, is commonly used for cardiovascular disorders treatment including atherosclerosis. There have been only a few researches on its chemical components, and no detailed report has appeared on its fatty acids. To develop a simple and effective method for the extraction of total fatty acids from Tabanus bivittatus Mats., the Soxhlet extraction (SE) condition was optimized with response surface methodology. The fatty acid composition of the extract were determined by GC-MS with previous derivatization to fatty acid methyl esters (FAMEs). The major fatty acids in Tabanus bivittatus Mats. were oleic acid, palmitic acid, linoleic acid, palmitoleic acid, and stearic acid, and the unsaturated fatty acids occupy 63.9% of the total fatty acids.

scholarly journals Dietary Coleus Amboinicus Herb Decreases Ruminal Methanogenesis and Biohydrogenation, and Improves Meat Quality and Fatty Acid Composition in Longissimus Thoracis of Lambs

2021 ◽  
Author(s):  
Yulianri Rizki Yanza ◽  
Malgorzata Szumacher-Strabel ◽  
Dorota Lechniak ◽  
Sylwester Ślusarczyk ◽  
Pawel Kolodziejski ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Meat Quality ◽  
Methane Production ◽  
Fatty Acid Synthase ◽  
Unsaturated Fatty Acids ◽  
Biologically Active ◽  
Coleus Amboinicus

Abstract Background: This study aimed to investigate the effect of biologically active compounds (BAC) of Coleus amboinicus Lour. (CAL) herb fed to growing lambs on ruminal methane production, ruminal biohydrogenation of unsaturated fatty acids and meat characteristics. An in vitro trial (Experiment 1) comprising of control and three experimental diets (CAL constituting 10%, 15%, and 20% of the total diet) was conducted to determine an effective dose for in vivo experiments. After the in vitro trial, two in vivo experiments were conducted on six growing, rumen-cannulated lambs (Experiment 2) and 16 growing lambs (Experiment 3), which were assigned into the control (CON) and one experimental diet (20% of CAL). Several parameters were examined in vitro (pH, ammonia and VFA concentrations, protozoa, methanogens and select bacteria populations) and in vivo (methane production, digestibility, ruminal microorganism populations, meat quality, fatty acids profiles in rumen fluid and meat, transcript expression of 5 genes in meat). Results: The CAL lowered in vitro methane production by 51%. In the in vivo experiments, lambs fed CAL decreased methane production by 20% compared with the CON animals (Experiment 3), which corresponded to the reduced total methanogens counts in all experiments up to 28%, notably Methanobacteriales. In Experiment 3, CAL increased or tended to increase the numbers of Ruminococcus albus, Megasphaeraelsdenii, Butyrivibrioproteoclasticus, and Butyrivibriofibrisolvens. Dietary CAL suppressed the Holotricha population, but increased or tended to increase Entodiniomorpha population in Experiments 2 and 3. An increase in the polyunsaturated fatty acid (PUFA) proportion in the rumen of lambs was noted in response to the CAL diet, which was mainly attributable to the increase in C18:3 cis-9 cis-12 cis-15 (LNA) proportion. The CAL reduced the mRNA expressions of four investigated genes in meat (fatty acid synthase, stearoyl-CoA desaturase, lipoprotein lipase, and fatty acid desaturase 1). Conclusions:Summarizing, polyphenols of CAL (20% in diet) origin can mitigate ruminal methane production by inhibiting the methanogens communities. Supplementation of CAL also provides favorable conditions in the rumen by modulating ruminal bacteria involved in fermentation and biohydrogenation of fatty acids. CAL elevated the LNA concentration, which led to improved meat quality through increased deposition of n-3 PUFA.

scholarly journals Composition of fatty acids and tocopherols in peels, seeds and leaves of Sea buckthorn

2017 ◽  
Vol 10 (1) ◽  
pp. 29-34 ◽  
Author(s):  
Zuzana Burčová ◽  
František Kreps ◽  
Štefan Schmidt ◽  
Michal Jablonský ◽  
Aleš Ház ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Linolenic Acid ◽  
Palmitoleic Acid ◽  
Unsaturated Fatty Acids ◽  
Vaccenic Acid ◽  
Sea Buckthorn ◽  
Biologically Active ◽  
Gamma Tocopherol ◽  
Tocopherol Composition

Abstract Peels, seeds and leaves of the Sea buckthorn were extracted by methanol and chloroform and characterized in terms of the fatty acids (FA) and tocopherol composition. All morphological parts of Sea buckthorn contained these biologically active compounds useful in medicine, pharmacology, human nutrition and cosmetics. The highest amount of α-tocopherol was found in peels (1103 mg kg-1). The lowest content of α-tocopherol was found in leaves (659 mg kg-1). Delta-tocopherol was found in higher amount in peels 1757 mg kg-1. Seeds contained 95 mg kg-1 of delta-tocopherols. Gamma-tocopherol was found in seeds (459 mg kg-1), peels (188 mg kg-1) and in leaves (587 mg kg-1). β-tocopherol was present only in seeds (171 mg kg-1). Unsaturated fatty acids were dominant in all morphological parts of Sea buckthorn. The highest amounts of unsaturated fatty acids (92 rel. %) were determined in seeds. Dominant fatty acids of seeds were linoleic acid (37 %), α-linolenic acid (30 %) and vaccenic acid (20 %). Leaves were rich in α-linolenic acid (51 %). Dominant fatty acids of peels were oleic acid (16 %), palmitic acid (33 %) and palmitoleic acid (29 %).

Criteria for essential fatty acid deficiency in plasma as assessed by capillary column gas-liquid chromatography.

1987 ◽  
Vol 33 (10) ◽  
pp. 1869-1873 ◽  
Author(s):  
E N Siguel ◽  
K M Chee ◽  
J X Gong ◽  
E J Schaefer
Keyword(s):  
Fatty Acids ◽  
Liquid Chromatography ◽  
Fatty Acid ◽  
Capillary Column ◽  
Unsaturated Fatty Acids ◽  
Vaccenic Acid ◽  
Essential Fatty Acids ◽  
Gas Liquid Chromatography ◽  
Mead Acid ◽  
Total Fatty Acids

Abstract To develop criteria for deficiency of essential fatty acids (EFA), we used capillary-column gas-liquid chromatography to determine fatty acids (percentage of total fatty acids) in plasma obtained in the fasting state from 56 reference subjects and from 10 patients with intestinal fat malabsorption and suspected EFA deficiency. Fatty acid evaluations (percentage of total fatty acids) that allowed for a clear distinction (P less than 0.01) between reference subjects and patients, based on values two standard deviations below or above the reference mean, included values for linoleic acid (18:2w6) below 27%, and values for palmitic acid (16:0), palmitoleic acid (16:1w7), oleic acid (18:1w9), vaccenic acid (18:1w7), and Mead acid (20:3w9) exceeding 21%, 2.6%, 23.3%, 2.1%, and 0.21%, respectively. Ratios of total EFA to total non-EFA of less than 0.60 and of Mead acid to arachidonic acid of greater than 0.025 also served to identify patients, and were not found in reference subjects. Significant inverse correlations between percentages of plasma EFA and plasma mono-unsaturated fatty acids were noted. Our reference-interval data can be used to assess normality of plasma EFA status.

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