Substrate specificity, regioselectivity and cryptoregiochemistry of plant and animal ω-3 fatty acid desaturases

2000 ◽  
Vol 28 (6) ◽  
pp. 632-635 ◽  
Author(s):  
D. Meesapyodsuk ◽  
D. W. Reed ◽  
C. K. Savile ◽  
P. H. Buist ◽  
U. A. Schäfer ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Bond Cleavage ◽  
Isotope Effects ◽  
Fatty Acid Desaturases ◽  
Yeast Saccharomyces Cerevisiae ◽  
Kinetic Isotope ◽  
Acid Analogue ◽  
And Function

In order to define the substrate requirements, regiochemistry and cryptoregiochemistry of the ω-3 fatty acid desaturases involved in polyunsaturated fatty acid formation, the genes Fad3 and fat-1 from Brassica napus and the nematode Caenorhabditis elegans respectively were expressed in baker's yeast (Saccharomyces cerevisiae). Various fatty acids, including deuterium-labelled thia-fatty acids, were supplied to growing cultures of transformed yeast. The results from GC-MS analysis of the desaturated products indicate that both the plant and animal desaturases act on unsaturated substrates of 16–20 carbons with a preference for ω-6-unsaturated fatty acids. The regioselectivities of both enzymes were confirmed to be that of ω-3 desaturases. The primary deuterium kinetic isotope effects at C-15 and C-16 of a C18 fatty acid analogue were measured via competitive incubation experiments. Whereas kH/kD at the ω-3 position was shown to be large, essentially no kinetic isotope effect at the ω-2 position was observed for the plant or the nematode enzymes. These results indicate that ω-3 desaturation is initiated by an energetically difficult C-H bond cleavage at the carbon closer to the carboxyl terminus. These results will be discussed in the context of a general model relating the structure and function of membrane-bound fatty acid desaturases featuring different regioselectivities.

scholarly journals Comparative Analysis of Fatty Acid Desaturases in Cyanobacterial Genomes

2008 ◽  
Vol 2008 ◽  
pp. 1-25 ◽  
Author(s):  
Xiaoyuan Chi ◽  
Qingli Yang ◽  
Fangqing Zhao ◽  
Song Qin ◽  
Yu Yang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Unsaturated Fatty Acids ◽  
Fatty Acid Desaturases ◽  
Highly Unsaturated Fatty Acids ◽  
Acyl Lipid ◽  
Cyanobacterial Species ◽  
Hydrocarbon Chains ◽  
Lipid Desaturation ◽  
Calcareous Rock

Fatty acid desaturases are enzymes that introduce double bonds into the hydrocarbon chains of fatty acids. The fatty acid desaturases from 37 cyanobacterial genomes were identified and classified based upon their conserved histidine-rich motifs and phylogenetic analysis, which help to determine the amounts and distributions of desaturases in cyanobacterial species. The filamentous orN2-fixing cyanobacteria usually possess more types of fatty acid desaturases than that of unicellular species. The pathway of acyl-lipid desaturation for unicellular marine cyanobacteriaSynechococcusandProchlorococcusdiffers from that of other cyanobacteria, indicating different phylogenetic histories of the two genera from other cyanobacteria isolated from freshwater, soil, or symbiont. StrainGloeobacter violaceusPCC 7421 was isolated from calcareous rock and lacks thylakoid membranes. The types and amounts of desaturases of this strain are distinct to those of other cyanobacteria, reflecting the earliest divergence of it from the cyanobacterial line. Three thermophilic unicellular strains,Thermosynechococcus elongatusBP-1 and twoSynechococcusYellowstone species, lack highly unsaturated fatty acids in lipids and contain only oneΔ9desaturase in contrast with mesophilic strains, which is probably due to their thermic habitats. Thus, the amounts and types of fatty acid desaturases are various among different cyanobacterial species, which may result from the adaption to environments in evolution.

EFFECT OF GINGER, LEMURU FISH OIL SAPONIFICATION AND OLIVE OIL ON COMPOSITION FATTY ACID OF BEEF

2014 ◽  
Vol 4 (1) ◽  
pp. 31-39
Author(s):  
Siwitri Kadarsih
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fish Oil ◽  
Olive Oil ◽  
Rice Bran ◽  
Dry Matter ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Omega 3 ◽  
Omega 6

The objective was to get beef that contain unsaturated fatty acids (especially omega 3 and 6), so as to improve intelligence, physical health for those who consume. The study design using CRD with 3 treatments, each treatment used 4 Bali cattle aged approximately 1.5 years. Observations were made 8 weeks. Pasta mixed with ginger provided konsentrat. P1 (control); P2 (6% saponification lemuru fish oil, olive oil 1%; rice bran: 37.30%; corn: 62.70%; KLK: 7%, ginger paste: 100 g); P3 (lemuru fish oil saponification 8%, 2% olive oil; rice bran; 37.30; corn: 62.70%; KLK: 7%, ginger paste: 200 g). Konsentrat given in the morning as much as 1% of the weight of the cattle based on dry matter, while the grass given a minimum of 10% of the weight of livestock observation variables include: fatty acid composition of meat. Data the analyzies qualitative. The results of the study showed that the composition of saturated fatty acids in meat decreased and an increase in unsaturated fatty acids, namely linoleic acid (omega 6) and linolenic acid (omega 3), and deikosapenta deikosaheksa acid.Keywords : 

scholarly journals Explore the gene network regulating the composition of fatty acids in cottonseed

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lihong Ma ◽  
Xinqi Cheng ◽  
Chuan Wang ◽  
Xinyu Zhang ◽  
Fei Xue ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Linolenic Acid ◽  
Gene Network ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Accumulation Pattern ◽  
Time Points ◽  
Expression Characteristics

Abstract Background Cottonseed is one of the major sources of vegetable oil. Analysis of the dynamic changes of fatty acid components and the genes regulating the composition of fatty acids of cottonseed oil is of great significance for understanding the biological processes underlying biosynthesis of fatty acids and for genetic improving the oil nutritional qualities. Results In this study, we investigated the dynamic relationship of 13 fatty acid components at 12 developmental time points of cottonseed (Gossypium hirsutum L.) and generated cottonseed transcriptome of the 12 time points. At 5–15 day post anthesis (DPA), the contents of polyunsaturated linolenic acid (C18:3n-3) and saturated stearic acid (C18:0) were higher, while linoleic acid (C18:2n-6) was mainly synthesized after 15 DPA. Using 5 DPA as a reference, 15,647 non-redundant differentially expressed genes were identified in 10–60 DPA cottonseed. Co-expression gene network analysis identified six modules containing 3275 genes significantly associated with middle-late seed developmental stages and enriched with genes related to the linoleic acid metabolic pathway and α-linolenic acid metabolism. Genes (Gh_D03G0588 and Gh_A02G1788) encoding stearoyl-ACP desaturase were identified as hub genes and significantly up-regulated at 25 DPA. They seemed to play a decisive role in determining the ratio of saturated fatty acids to unsaturated fatty acids. FAD2 genes (Gh_A13G1850 and Gh_D13G2238) were highly expressed at 25–50 DPA, eventually leading to the high content of C18:2n-6 in cottonseed. The content of C18:3n-3 was significantly decreased from 5 DPA (7.44%) to 25 DPA (0.11%) and correlated with the expression characteristics of Gh_A09G0848 and Gh_D09G0870. Conclusions These results contribute to our understanding on the relationship between the accumulation pattern of fatty acid components and the expression characteristics of key genes involved in fatty acid biosynthesis during the entire period of cottonseed development.

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 Meat Quality, Fatty Acid Content and NMR Metabolic Profile of Dorper Sheep Supplemented with Bypass Fats

Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1133
Author(s):  
Atique Ahmed Behan ◽  
Muhammad Tayyab Akhtar ◽  
Teck Chwen Loh ◽  
Sharida Fakurazi ◽  
Ubedullah Kaka ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Meat Quality ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Fatty Acid Content ◽  
Basal Diet ◽  
Negative Influence ◽  
Significant Difference ◽  
Dorper Sheep

The supplementation of rumen bypass fat (RBF) has remained one of the preferred approaches used to decrease undesirable saturated fatty acids (FA) and increase beneficial unsaturated FA in the meat. This study was planned to evaluate the influences of rumen bypass fats on meat quality, fatty acid and metabolic profiles in male Dorper sheep (n = 36) with 24.66 ± 0.76 kg (mean ± standard error) initial body weight. Treatment comprised a basal diet (30:70 rice straw to concentrate) with no added RBF as a control (CON), basal diet with prilled fat (PF), basal diet with prilled fat plus lecithin (PFL) and basal diet with calcium soap of palm fatty acids (CaS). The findings revealed that cooking loss, drip loss and shear force in longissimus dorsi (LD) muscle were not affected by RBF supplementation, while meat pH was significantly higher in the CaS on aging day 1. However, the diet supplemented with prilled fat and lecithin modified the meat’s fatty acid profile significantly by increasing unsaturated fatty acids and decreasing saturated fats. The relative quantification of the major differentiating metabolites found in LD muscle of sheep showed that total cholesterol, esterified cholesterol, choline, glycerophosphocholine and glycerophospholipids were significantly lower in CaS and PFL diets, while glycerol and sphingomyelin were significantly higher in CaS and PFL diets. Most of the metabolites in the liver did not show any significant difference. Based on our results, the supplementation of protected fats did not have a negative influence on meat quality and the meat from Dorper sheep fed prilled fat with lecithin contained more healthy fatty acids compared to other diets.

Modifying egg fatty acid content by supplementation of laying hen diets with palm olein oil (POO)

2009 ◽  
Vol 2009 ◽  
pp. 212-212
Author(s):  
S J Hosseini Vashan ◽  
N Afzali ◽  
A Golian ◽  
M Malekaneh ◽  
A Allahressani
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Acid Content ◽  
Palm Olein ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Fatty Acid Content ◽  
Processing Plant ◽  
Optimum Level ◽  
Olein Oil

Palm oil is the most abundant of all oils produced globally. It is very high in saturated fatty acids specifically palmitic acid, but other fatty acids (monounsaturated (MUFA) and polyunsaturated) are presented at low concentrations. In the processing plant some high amount of oleic acid with some other unsaturated fatty acids are extracted and marketed as Palm olein oil, and used to reduce blood or egg cholesterol (Rievelles et al., 1994). The objective of this study was to determine the optimum level of dietary palm olein oil required to enrich the mono-unsaturated fatty acid content of yolk, egg cholesterol and antibody titre.

Relationships between muscle membrane lipids, fiber type, and enzyme activities in sedentary and exercised rats

1995 ◽  
Vol 269 (5) ◽  
pp. R1154-R1162 ◽  
Author(s):  
A. D. Kriketos ◽  
D. A. Pan ◽  
J. R. Sutton ◽  
J. F. Hoh ◽  
L. A. Baur ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Extensor Digitorum Longus ◽  
Unsaturated Fatty Acids ◽  
Citrate Synthase ◽  
Fiber Type ◽  
Saturated Fatty Acids ◽  
Extensor Digitorum ◽  
Female Rats ◽  
Muscle Membrane

Insulin resistance in skeletal muscle is associated with 1) relative increases in the proportion of glycolytic and fast-twitch muscle fibers and decreases in the proportion of more oxidative fibers and 2) a higher proportion of the saturated fatty acids in membrane structural lipids. Exercise is known to improve insulin action. The aims of the current studies were 1) to investigate the relationship between muscle fiber type and membrane fatty acid composition and 2) to determine how voluntary exercise might influence both variables. In sedentary Wistar rats in experiment 1, increased amounts of unsaturated fatty acids were found in the more oxidative insulin-sensitive red quadriceps and soleus muscles, whereas reduced levels of polyunsaturated fatty acids were found in primarily glycolytic white quadriceps muscles. In experiment 2, voluntary running-wheel exercise by adult female rats over 45 days resulted in reduced proportions of type IIb fibers (P = 0.01) and increased proportions of type IIa/IIx fibers (P = 0.03) in extensor digitorum longus muscle. The magnitude of these changes was related to the distance run (r = -0.73, P = 0.04; r = 0.79, P = 0.02, respectively). Exercise significantly increased oxidative capacity, as assessed by the proportion of intensely NADH-stained fibers (P = 0.0004) and citrate synthase (P = 0.003) and hexokinase (P = 0.04) activities. Citrate synthase activity was also increased by exercise in soleus muscle, where, as expected, no fiber type changes were detected. No significant differences in the fatty acid profile of soleus and extensor digitorum longus were found between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Saccharomyces kluyveri FAD3 encodes an ω3 fatty acid desaturase

Microbiology ◽  
2004 ◽  
Vol 150 (6) ◽  
pp. 1983-1990 ◽  
Author(s):  
Takahiro Oura ◽  
Susumu Kajiwara
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Linolenic Acid ◽  
Functional Characterization ◽  
Fatty Acid Desaturase ◽  
Fatty Acid Desaturases ◽  
Desaturase Gene ◽  
Saccharomyces Kluyveri ◽  
Fatty Acid Desaturase Gene

Fungi, like plants, are capable of producing the 18-carbon polyunsaturated fatty acids linoleic acid and α-linolenic acid. These fatty acids are synthesized by catalytic reactions of Δ12 and ω3 fatty acid desaturases. This paper describes the first cloning and functional characterization of a yeast ω3 fatty acid desaturase gene. The deduced protein encoded by the Saccharomyces kluyveri FAD3 gene (Sk-FAD3) consists of 419 amino acids, and shows 30–60 % identity with Δ12 fatty acid desaturases of several eukaryotic organisms and 29–31 % identity with ω3 fatty acid desaturases of animals and plants. During Sk-FAD3 expression in Saccharomyces cerevisiae, α-linolenic acid accumulated only when linoleic acid was added to the culture medium. The disruption of Sk-FAD3 led to the disappearance of α-linolenic acid in S. kluyveri. These findings suggest that Sk-FAD3 is the only ω3 fatty acid desaturase gene in this yeast. Furthermore, transcriptional expression of Sk-FAD3 appears to be regulated by low-temperature stress in a manner different from the other fatty acid desaturase genes in S. kluyveri.

scholarly journals Fatty acid profile and composition of milk protein fraction in dairy cows fed long-chain unsaturated fatty acids during the transition period

2013 ◽  
Vol 42 (11) ◽  
pp. 813-823 ◽  
Author(s):  
Francisco Palma Rennó ◽  
José Esler de Freitas Júnior ◽  
Jefferson Rodrigues Gandra ◽  
Lenita Camargo Verdurico ◽  
Marcos Veiga dos Santos ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Dairy Cows ◽  
Fatty Acid Profile ◽  
Protein Fraction ◽  
Milk Protein ◽  
Unsaturated Fatty Acids ◽  
Transition Period ◽  
Long Chain
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