scholarly journals An Oil Hyper-Accumulator Mutant Highlights Peroxisomal ATP Import as a Regulatory Step for Fatty Acid Metabolism in Aurantiochytrium limacinum

Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2680
Author(s):  
Etienne Deragon ◽  
Martin Schuler ◽  
Riccardo Aiese Aiese Cigliano ◽  
Younès Dellero ◽  
Gregory Si Si Larbi ◽  
...  

Thraustochytrids are marine protists that naturally accumulate triacylglycerol with long chains of polyunsaturated fatty acids, such as ω3-docosahexaenoic acid (DHA). They represent a sustainable response to the increasing demand for these “essential” fatty acids (FAs). Following an attempt to transform a strain of Aurantiochytrium limacinum, we serendipitously isolated a clone that did not incorporate any recombinant DNA but contained two to three times more DHA than the original strain. Metabolic analyses indicated a deficit in FA catabolism. However, whole transcriptome analysis did not show down-regulation of genes involved in FA catabolism. Genome sequencing revealed extensive DNA deletion in one allele encoding a putative peroxisomal adenylate transporter. Phylogenetic analyses and yeast complementation experiments confirmed the gene as a peroxisomal adenylate nucleotide transporter (AlANT1), homologous to yeast ScANT1 and plant peroxisomal adenylate nucleotide carrier AtPNC genes. In yeast and plants, a deletion of the peroxisomal adenylate transporter inhibits FA breakdown and induces FA accumulation, a phenotype similar to that described here. In response to this metabolic event, several compensatory mechanisms were observed. In particular, genes involved in FA biosynthesis were upregulated, also contributing to the high FA accumulation. These results support AlANT1 as a promising target for enhancing DHA production in Thraustochytrids.

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Amor Slama ◽  
Ammar Cherif ◽  
Sadok Boukhchina

Cereals constitute a major source of human and animal nutrition. In spite of the extensive production of numerous cereal species, some information is unavailable in terms of lipid composition. Due to the oil increasing demand by the overgrowth of the world population, oleaginous species have encountered problems in recent years. In order to find new sources of edible oil, the aim of this study was to describe the importance of seventeen varieties oil of seven cereal species. Oils were extracted by the Soxhlet method, and fatty acids were measured by gas chromatography. The present study demonstrated that the lipid content of cereal seeds ranged from 1.42% to 5.97%. In average, oat, millet, and maize had significantly higher lipid content, respectively, 5.97%, 5.06%, and 4.71%. The main fatty acid recorded in the studied cereal species, except oat, was linoleic acid C18 : 2 (ω6). Regarding the essential fatty acids linoleic acid C18 : 2 and linolenic acid C18 : 3 (ω3), the oil of all studied species, except oat, was rich in ω6 fatty acids (47.50 to 60.13%) and poor in ω3 (0.45% to 5.33%). The content of unsaturated fatty acids in all studied species ranged from 77.22 to 81.89%. Cereal oil was considered as highly unsaturated oil with the presence of the essential fatty acids necessary for human health. Therefore, cereal oils could be commercialized in small quantities in pharmacies or parapharmacies.


2020 ◽  
Vol 638 ◽  
pp. 107-121 ◽  
Author(s):  
BS Rangel ◽  
NE Hussey ◽  
Y Niella ◽  
LA Martinelli ◽  
AD Gomes ◽  
...  

Throughout evolutionary history, elasmobranchs have developed diverse reproductive strategies. Little focused work, however, has addressed how neonatal nutritional state is affected by differing degrees of maternal investment associated with these markedly different reproductive strategies. To investigate the effect of maternal investment on the nutritional quality of pups during the early life history of an extremely viviparous elasmobranch, quantitative biomarker analysis including lipids, fatty acids and stable isotopes was conducted. Using the cownose ray Rhinoptera bonasus (histotrophic viviparous) as a model, we found that pups were initially born in a positive nutritional state, enriched in physiologically important essential fatty acids and nitrogen and carbon stable isotope values (δ15N and δ13C), a result of maternal intrauterine transfer. A systematic decrease in some fatty acids and δ15N values, as well as a decrease in cholesterol with growth, confirmed that these substrates were derived from maternal resources and used in initial metabolic processes following birth. An observed increase in condition factor, plasma essential fatty acids and triglyceride:cholesterol ratio with increasing body size identified a progression towards successful independent foraging with pups not displaying marked nutritional deficiency or fasting phases. Our multi-tracer approach allowed the identification of 2 size classes of young rays (<50 and <70 cm disc width) that displayed distinct physiological states. Since prenatal maternal investment is critical for offspring condition and to promote successful foraging post birth, understanding the trophic ecology and physiological state of pups during their first year is critical to guide management and conservation within nursery grounds.


2018 ◽  
Vol 28 (4) ◽  
pp. 1219-1225
Author(s):  
Filip Jovanovski ◽  
Toni Mitrovski ◽  
Viktorija Bezhovska

Food is not just a pleasure in life, it is also an important factor for our health. Human nutrition is a mixture of nutrients, which are the only source of energy needed for survival. Energy-poor diet endangers many life functions, and above all the working ability. In the world, the meaning of the diet is very serious, and hence the demands for a –rational, healthy and safe diet are growing. Human nutrition contains saturated and unsaturated fatty acids. Essential fatty acids (EFAs) must be ingested in everyday diet because the body does not produce it. They are very important for human health. They are present in each cell of the human body and are an important factor for the normal growth, development and functioning of cells, muscles, nerves and organs. They are also used in the production of certain hormones - such as prostaglandins, which are crucial for the performance of certain important processes. The deficit from EFAs is due to a number of health problems, including more serious diseases.


2017 ◽  
Vol 10 (1) ◽  
pp. 92-99 ◽  
Author(s):  
Hércules Rezende Freitas

Polyunsaturated fatty acids (PUFAs) comprise about 35-40% of the total lipid content from green algaeChlorella, reaching up to 24% linoleic acid and 27% α-linolenic acid inC. vulgaris. Also, microalgae nutrient composition may be modulated by changes in the culture medium, increasing fatty acid and microelement concentrations in the algae biomass. PUFAs, such as α-linolenic (n-3) and linoleic (n-6) acids, as well as its derivatives, are considered essential for dietary consumption, and their ability to regulate body chemistry has been recently explored in depth. A balanced fatty acid consumption is shown to counteract the negative effects of western diets, such as chronic inflammation and glucose intolerance. In this brief commentary, technological and practical uses ofC. vulgarisare explored as means to improve dietary quality and, ultimately, human health.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pianpian Wu ◽  
Martin J. Kainz ◽  
Fernando Valdés ◽  
Siwen Zheng ◽  
Katharina Winter ◽  
...  

AbstractClimate change scenarios predict increases in temperature and organic matter supply from land to water, which affect trophic transfer of nutrients and contaminants in aquatic food webs. How essential nutrients, such as polyunsaturated fatty acids (PUFA), and potentially toxic contaminants, such as methylmercury (MeHg), at the base of aquatic food webs will be affected under climate change scenarios, remains unclear. The objective of this outdoor mesocosm study was to examine how increased water temperature and terrestrially-derived dissolved organic matter supply (tDOM; i.e., lake browning), and the interaction of both, will influence MeHg and PUFA in organisms at the base of food webs (i.e. seston; the most edible plankton size for zooplankton) in subalpine lake ecosystems. The interaction of higher temperature and tDOM increased the burden of MeHg in seston (< 40 μm) and larger sized plankton (microplankton; 40–200 μm), while the MeHg content per unit biomass remained stable. However, PUFA decreased in seston, but increased in microplankton, consisting mainly of filamentous algae, which are less readily bioavailable to zooplankton. We revealed elevated dietary exposure to MeHg, yet decreased supply of dietary PUFA to aquatic consumers with increasing temperature and tDOM supply. This experimental study provides evidence that the overall food quality at the base of aquatic food webs deteriorates during ongoing climate change scenarios by increasing the supply of toxic MeHg and lowering the dietary access to essential nutrients of consumers at higher trophic levels.


1960 ◽  
Vol 235 (12) ◽  
pp. 3379-3384 ◽  
Author(s):  
Armand J. Fulco ◽  
James F. Mead

Sign in / Sign up

Export Citation Format

Share Document