Delta 5 Fatty Acid Desaturase Upregulates the Synthesis of Polyunsaturated Fatty Acids in the Marine Diatom Phaeodactylum tricornutum

AbstractAlgal lipids are important fuel storage molecules in algae and a currency for energy transfer in the marine food chain as well as materials for biofuel production, but their production and regulation are not well understood in many species including the common coastal phytoplankton Eutreptiella spp. Here, using gas chromatography-tandem mass spectrometry (GC/MS/MS), we discovered 24 types of fatty acids (FAs) in Eutreptiella sp. with a relatively high proportion of long chain unsaturated FAs. The abundances of C16, C18 and saturated FAs decreased when phosphate in the culture medium was depleted. Among the 24 FAs, docosahexaenoic acid (22:6) and eicosapentaenoic acid (20:5) were the most abundant, suggesting that Eutreptiella sp. preferentially invests in the synthesis of very long chain polyunsaturated fatty acids (VLCPFA). Further transcriptomic analysis revealed that Eutreptiella sp. likely synthesizes VLCPFA via Δ8 pathway and uses type I and II fatty acid synthases. Using RT-qPCR, we found that some of the lipid production genes, such as β-ketoacyl-ACP reductase, fatty acid desaturase, acetyl-CoA carboxylase, acyl carrier protein, Δ8 desaturase, and Acyl-ACP thioesterase, were more actively expressed during light period. Besides, two carbon-fixation genes were more highly expressed in the high lipid illuminated cultures, suggesting a linkage between photosynthesis and lipid production.

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Characterization and molecular docking of new Δ17 fatty acid desaturase genes from Rhizophagus irregularis and Octopus bimaculoides

RSC Advances ◽

10.1039/c9ra00535h ◽

2019 ◽

Vol 9 (12) ◽

pp. 6871-6880 ◽

Cited By ~ 2

Author(s):

Chunchi Rong ◽

Haiqin Chen ◽

Xin Tang ◽

Zhennan Gu ◽

Jianxin Zhao ◽

...

Keyword(s):

Fatty Acids ◽

Molecular Docking ◽

Fatty Acid ◽

Polyunsaturated Fatty Acids ◽

Fatty Acid Desaturase ◽

Rhizophagus Irregularis ◽

Fatty Acid Desaturases ◽

Key Enzymes

Fatty acid desaturases are key enzymes in the biosynthesis of n-3 polyunsaturated fatty acids (PUFAs) via conversion of n-6 polyunsaturates to their n-3 counterparts.

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Long-chain polyunsaturated fatty acids, gestation duration, and birth size: a Mendelian randomization study using fatty acid desaturase variants

American Journal of Clinical Nutrition ◽

10.1093/ajcn/nqy079 ◽

2018 ◽

Vol 108 (1) ◽

pp. 92-100 ◽

Cited By ~ 12

Author(s):

Jonathan Y Bernard ◽

Hong Pan ◽

Izzuddin M Aris ◽

Margarita Moreno-Betancur ◽

Shu-E Soh ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Polyunsaturated Fatty Acids ◽

Mendelian Randomization ◽

Fatty Acid Desaturase ◽

Minor Allele ◽

Survival Models ◽

Birth Date ◽

Birth Size ◽

Long Chain

ABSTRACT Background In randomized trials, supplementation of n–3 (ω-3) long-chain polyunsaturated fatty acids (LC-PUFAs) during pregnancy has resulted in increased size at birth, which is attributable to longer gestation. Objective We examined this finding by using a Mendelian randomization approach utilizing fatty acid desaturase (FADS) gene variants affecting LC-PUFA metabolism. Design As part of a tri-ethnic mother-offspring cohort in Singapore, 35 genetic variants in FADS1, FADS2, and FADS3 were genotyped in 898 mothers and 1103 offspring. Maternal plasma n–3 and n–6 PUFA concentrations at 26–28 wk of gestation were measured. Gestation duration was derived from an ultrasound dating scan in early pregnancy and from birth date. Birth length and weight were measured. Eight FADS variants were selected through a tagging-SNP approach and examined in association with PUFA concentrations, gestation duration among spontaneous labors, and birth size with the use of ethnicity-adjusted linear regressions and survival models that accounted for the competing risks of induced labor and prelabor cesarean delivery. Results Maternal FADS1 variant rs174546, tagging for 8 other variants located on FADS1 and FADS2, was strongly related to plasma n–6 but not n–3 LC-PUFA concentrations. Offspring and maternal FADS3 variants were associated with gestation duration among women who had spontaneous labor: each copy of rs174450 minor allele C was associated with a shorter gestation by 2.2 d (95% CI: 0.9, 3.4 d) and 1.9 d (0.7, 3.0 d) for maternal and offspring variants, respectively. In survival models, rs174450 minor allele homozygotes had reduced time to delivery after spontaneous labor compared with major allele homozygotes [HR (95% CI): 1.51 (1.18, 1.95) and 1.51 (1.20, 1.89) for mothers and offspring, respectively]. Conclusions With the use of a Mendelian randomization approach, we observed associations between FADS variants and gestation duration. This suggests a potential role of LC-PUFAs in gestation duration. This trial was registered at http://www.clinicaltrials.gov as NCT01174875.

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Long-Chain Polyunsaturated Fatty Acids, Homocysteine at Birth and Fatty Acid Desaturase Gene Cluster Polymorphisms Are Associated with Children’s Processing Speed up to Age 9 Years

Nutrients ◽

10.3390/nu13010131 ◽

2020 ◽

Vol 13 (1) ◽

pp. 131

Author(s):

Cristina Campoy ◽

Hatim Azaryah ◽

Francisco J. Torres-Espínola ◽

Cristina Martínez-Zaldívar ◽

José Antonio García-Santos ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Polyunsaturated Fatty Acids ◽

Gene Cluster ◽

Processing Speed ◽

Methylenetetrahydrofolate Reductase ◽

Fatty Acid Desaturase ◽

Long Term Effects ◽

Long Chain

Both pre- and early postnatal supplementation with docosahexaenoic acid (DHA), arachidonic acid (AA) and folate have been related to neural development, but their long-term effects on later neural function remain unclear. We evaluated the long-term effects of maternal prenatal supplementation with fish-oil (FO), 5-methyltetrahydrofolate (5-MTHF), placebo or FO + 5-MTHF, as well as the role of fatty acid desaturase (FADS) gene cluster polymorphisms, on their offspring’s processing speed at later school age. This study was conducted in NUHEAL children at 7.5 (n = 143) and 9 years of age (n = 127). Processing speed tasks were assessed using Symbol Digit Modalities Test (SDMT), Children Color Trails Test (CCTT) and Stroop Color and Word Test (SCWT). Long-chain polyunsaturated fatty acids, folate and total homocysteine (tHcy) levels were determined at delivery from maternal and cord blood samples. FADS and methylenetetrahydrofolate reductase (MTHFR) 677 C > T genetic polymorphisms were analyzed. Mixed models (linear and logistic) were performed. There were significant differences in processing speed performance among children at different ages (p < 0.001). The type of prenatal supplementation had no effect on processing speed in children up to 9 years. Secondary exploratory analyses indicated that children born to mothers with higher AA/DHA ratio at delivery (p < 0.001) and heterozygotes for FADS1 rs174556 (p < 0.05) showed better performance in processing speed at 9 years. Negative associations between processing speed scores and maternal tHcy levels at delivery were found. Our findings suggest speed processing development in children up to 9 years could be related to maternal factors, including AA/DHA and tHcy levels, and their genetic background, mainly FADS polymorphism. These considerations support that maternal prenatal supplementation should be quantitatively adequate and individualized to obtain better brain development and mental performance in the offspring.

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