Quantitative and Qualitative Analyses of Triacylglycerol Production in the Wild-Type Cyanobacterium Synechocystis sp. PCC 6803 and the Strain Expressing AtfA from Acinetobacter baylyi ADP1

2020 ◽  
Vol 61 (9) ◽  
pp. 1537-1547 ◽  
Author(s):  
Motoki Tanaka ◽  
Toshiki Ishikawa ◽  
So Tamura ◽  
Yujiro Saito ◽  
Maki Kawai-Yamada ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Neutral Lipid ◽  
Saturated Fatty Acids ◽  
Wax Ester ◽  
Wild Type ◽  
Acinetobacter Baylyi ◽  
Lipid Species ◽  
Acinetobacter Baylyi Adp1 ◽  
Synechocystis Sp ◽  
Pcc 6803

Abstract Although cyanobacteria do not possess wax ester synthase/acyl-CoA:diacylglycerol acyltransferase (WS/DGAT), the bacterial enzyme for triacylglycerol (TAG) production, there have been several studies reporting the accumulation of TAG-like compounds in cyanobacteria. In this study, we aimed to evaluate TAG productivity of the ΔrecJ::atfA strain of Synechocystis sp. PCC 6803 generated by inserting atfA encoding WS/DGAT from Acinetobacter baylyi ADP1 into recJ (sll1354), together with the wild type (WT) and the gene-disrupted strain of slr2103 having homology with eukaryotic DGAT2 gene family (Δ2103). Thin-layer chromatography (TLC) of neutral lipids or isolation of the neutral lipid-enriched fraction followed by gas chromatography or liquid chromatography–tandem mass spectrometry was employed for analyses. The ΔrecJ::atfA strain accumulated 0.508 nmol ml−1OD730−1 of TAG after a week of incubation at 100 μmol photons m−2 s−1. The saturated fatty acids C16:0 and C18:0 accounted for about 50% and 20% of the TAG fatty acids, respectively, suggesting that de novo-synthesized fatty acids were preferentially incorporated into TAG molecules. When the neutral lipid profile of the lipid extracts was examined by TLC, a spot located in a slightly lower position compared with the TAG standard was detected in WT but not in the Δ2103 strain. TAG accumulation levels of both strains was only 0.01–0.03 nmol ml−1OD730−1, but the fatty acid composition was substantially different from that of the background. These results suggest that trace amounts of TAG can be produced in Synechocystis cells by enzymes other than Slr2103, and major constituents of the TAG-like spot are unknown lipid species produced by Slr2103.

scholarly journals Obese Mice with Dyslipidemia Exhibit Meibomian Gland Hypertrophy and Alterations in Meibum Composition and Aqueous Tear Production

2020 ◽  
Vol 21 (22) ◽  
pp. 8772
Author(s):  
Eugene A. Osae ◽  
Tiffany Bullock ◽  
Madhavi Chintapalati ◽  
Susanne Brodesser ◽  
Samuel Hanlon ◽  
...  
Keyword(s):  
Fatty Acids ◽  
High Fat Diet ◽  
Saturated Fatty Acids ◽  
Principal Component ◽  
Meibomian Gland ◽  
Epididymal Adipose Tissue ◽  
Esi Ms ◽  
Diet Induced Obesity ◽  
Tear Production ◽  
Lipid Species

Background: Dyslipidemia may be linked to meibomian gland dysfunction (MGD) and altered meibum lipid composition. The purpose was to determine if plasma and meibum cholesteryl esters (CE), triglycerides (TG), ceramides (Cer) and sphingomyelins (SM) change in a mouse model of diet-induced obesity where mice develop dyslipidemia. Methods: Male C57/BL6 mice (8/group, age = 6 wks) were fed a normal (ND; 15% kcal fat) or an obesogenic high-fat diet (HFD; 42% kcal fat) for 10 wks. Tear production was measured and meibography was performed. Body and epididymal adipose tissue (eAT) weights were determined. Nano-ESI-MS/MS and LC-ESI-MS/MS were used to detect CE, TG, Cer and SM species. Data were analyzed by principal component analysis, Pearson’s correlation and unpaired t-tests adjusted for multiple comparisons; significance set at p ≤ 0.05. Results: Compared to ND mice, HFD mice gained more weight and showed heavier eAT and dyslipidemia with higher levels of plasma CE, TG, Cer and SM. HFD mice had hypertrophic meibomian glands, increased levels of lipid species acylated by saturated fatty acids in plasma and meibum and excessive tear production. Conclusions: The majority of meibum lipid species with saturated fatty acids increased with HFD feeding with evidence of meibomian gland hypertrophy and excessive tearing. The dyslipidemia is associated with altered meibum composition, a key feature of MGD.

scholarly journals Untargeted Lipidomics Analysis of the Cyanobacterium Synechocystis sp. PCC 6803: Lipid Composition Variation in Response to Alternative Cultivation Setups and to Gene Deletion

2020 ◽  
Vol 21 (23) ◽  
pp. 8883
Author(s):  
Weronika Hewelt-Belka ◽  
Ágata Kot-Wasik ◽  
Paula Tamagnini ◽  
Paulo Oliveira
Keyword(s):  
Lipid Composition ◽  
Gene Deletion ◽  
Total Lipid Content ◽  
Outer Membrane Vesicles ◽  
Cell Factories ◽  
Composition Variation ◽  
Lipid Species ◽  
Alternative Cultivation ◽  
Synechocystis Sp ◽  
Pcc 6803

Cyanobacteria play an important role in several ecological environments, and they are widely accepted to be the ancestors of chloroplasts in modern plants and green algae. Cyanobacteria have become attractive models for metabolic engineering, with the goal of exploring them as microbial cell factories. However, the study of cyanobacterial lipids’ composition and variation, and the assessment of the lipids’ functional and structural roles have been largely overlooked. Here, we aimed at expanding the cyanobacterial lipidomic analytical pipeline by using an untargeted lipidomics approach. Thus, the lipid composition variation of the model cyanobacterium Synechocystis sp. PCC 6803 was investigated in response to both alternative cultivation setups and gene deletion. This approach allowed for detecting differences in total lipid content, alterations in fatty-acid unsaturation level, and adjustments of specific lipid species among the identified lipid classes. The employed method also revealed that the cultivation setup tested in this work induced a deeper alteration of the cyanobacterial cell lipidome than the deletion of a gene that results in a dramatic increase in the release of lipid-rich outer membrane vesicles. This study further highlights how growth conditions must be carefully selected when cyanobacteria are to be engineered and/or scaled-up for lipid or fatty acids production.

scholarly journals Lipid composition of the isolated rat intestinal microvillus membrane

1968 ◽  
Vol 109 (1) ◽  
pp. 51-59 ◽  
Author(s):  
G. G. Forstner ◽  
K. Tanaka ◽  
K. J. Isselbacher
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Neutral Lipid ◽  
Lipid Composition ◽  
Plasma Membranes ◽  
Membrane Lipids ◽  
Saturated Fatty Acids ◽  
Polar Lipids ◽  
Published Data ◽  
Microvillus Membrane

1. Rat intestinal microvillus plasma membranes were prepared from previously isolated brush borders and the lipid composition was analysed. 2. The molar ratio of cholesterol to phospholipid was greatest in the membranes and closely resembled that reported for myelin. 3. Unesterified cholesterol was the major neutral lipid. However, 30% of the neutral lipid fraction was accounted for by glycerides and fatty acid. 4. Five phospholipid components were identified and measured, including phosphatidylethanolamine, phosphatidylcholine, phosphatidylserine, sphingomyelin and lysophosphatidylcholine. Though phosphatidylethanolamine was the chief phospholipid, no plasmalogen was detected. 5. In contrast with other plasma membranes in the rat, the polar lipids of the microvillus membrane were rich in glycolipid. The cholesterol:polar lipid (phospholipid+glycolipid) ratio was about 1:3 for the microvillus membrane. Published data suggest that this ratio resembles that of the liver plasma membrane more closely than myelin or the erythrocyte membrane. 6. The fatty acid composition of membrane lipids was altered markedly by a single feeding of safflower oil. Membrane polar lipids did not contain significantly more saturated fatty acids than cellular polar lipids. Differences in the proportion of some fatty acids in membrane and cellular glycerides were noted. These differences may reflect the presence of specific membrane glycerides.

scholarly journals Effects of including a ruminally protected lipid supplement in the diet on the fatty acid composition of beef muscle

2003 ◽  
Vol 90 (3) ◽  
pp. 709-716 ◽  
Author(s):  
Nigel D. Scollan ◽  
Mike Enser ◽  
Suresh K. Gulati ◽  
Ian Richardson ◽  
Jeff D. Wood
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Neutral Lipid ◽  
Acid Composition ◽  
Saturated Fatty Acids ◽  
Fatty Acid Content ◽  
Control Treatment ◽  
Large Shift ◽  
Lipid Supplement

Enhancing the polyunsaturated fatty acid (PUFA) and decreasing the saturated fatty acid content of beef is an important target in terms of improving the nutritional value of this food for the consumer. The present study examined the effects of feeding a ruminally protected lipid supplement (PLS) rich in PUFA on the fatty acid composition of longissimus thoracis muscle and associated subcutaneous adipose tissue. Animals were fed ad libitum on grass silage plus one of three concentrate treatments in which the lipid source was either Megalac (rich in palmitic acid; 16:0) or PLS (soyabean, linseed and sunflower-seed oils resulting in an 18:2n−6:18:3n−3 value of 2·4:1). Treatment 1 contained 100g Megalac/kg (Mega, control); treatment 2 (PLS1) contained 54g Megalac/kg with 500g PLS/d fed separately; treatment 3 (PLS2) contained no Megalac and 1000g PLS/d fed separately. The PLS was considered as part of the overall concentrate allocation per d in maintaining an overall forage:concentrate value of 60:40 on a DM basis. Total dietary fat was formulated to be 0·07 of DM of which 0·04 was the test oil. Total intramuscular fatty acids (mg/100g muscle) were decreased by 0·31 when feeding PLS2 compared with Mega (P<0·05). In neutral lipid, the PLS increased the proportion of 18:2n−6 and 18:3n−3 by 2·7 and 4·1 on diets PLS1 and PLS2 v. Mega, respectively. Similar responses were noted for these fatty acids in phospholipid. The amounts or proportions of 20:4n−6, 20:5n−3 or 22:6n−3 were not influenced by diet whereas the amounts and proportions of 22:4n−6 and 22:5n−3 in phospholipid were decreased with inclusion of the PLS. The amounts of the saturated fatty acids, 14:0, 16:0 and 18:0, in neutral lipid were on average 0·37 lower on treatment PLS2 compared with Mega. Feeding the PLS also decreased the proportion of 16:0 in neutral lipid. The amount of 18:1n-9 (P=0·1) and the amount and proportion of 18:1 trans (P<0·01) were lower on treatments PLS1 and PLS2 in neutral lipid and phospholipid. Conjugated linoleic acid (cis-9, trans-11) was not influenced by diet in the major storage fraction for this fatty acid, neutral lipid. The PUFA:saturated fatty acids value was increased markedly (×2·5) with inclusion of the PLS (P<0·001) while the σn−6:n−3 value increased slightly (×1·2; P=0·015). The results suggest that the protected lipid used, which was rich in PUFA, had a high degree of protection from the hydrogenating action of rumen micro-organisms. The PLS resulted in meat with a lower content of total fat, decreased saturated fatty acids and much higher 18:2n−6 and 18:3n−3. The net result was a large shift in polyunsaturated: saturated fatty acids, 0·28 v. 0·08, on feeding PLS2 compared with Mega, respectively.

Rapid analysis and quantification of major neutral lipid species and free fatty acids by HPLC-ELSD from microalgae

2016 ◽  
Vol 118 (10) ◽  
pp. 1550-1556 ◽  
Author(s):  
Florentin Donot ◽  
Caroline Strub ◽  
Angélique Fontana ◽  
Nicolas Jouy ◽  
Christelle Delbes ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Neutral Lipid ◽  
Rapid Analysis ◽  
Lipid Species

scholarly journals The Malic Enzyme Is Required for Optimal Photoautotrophic Growth of Synechocystis sp. Strain PCC 6803 under Continuous Light but Not under a Diurnal Light Regimen

2004 ◽  
Vol 186 (23) ◽  
pp. 8144-8148 ◽  
Author(s):  
Terry M. Bricker ◽  
Shulu Zhang ◽  
Susan M. Laborde ◽  
Paul R. Mayer ◽  
Laurie K. Frankel ◽  
...  
Keyword(s):  
Malic Enzyme ◽  
Continuous Light ◽  
Light Conditions ◽  
Wild Type ◽  
Photoautotrophic Growth ◽  
Light Regimen ◽  
Synechocystis Sp ◽  
Pcc 6803

ABSTRACT A mutation was recovered in the slr0721 gene, which encodes the decarboxylating NADP+-dependent malic enzyme in the cyanobacterium Synechocystis sp. strain PCC 6803, yielding the mutant 3WEZ. Under continuous light, 3WEZ exhibits poor photoautotrophic growth while growing photoheterotrophically on glucose at rates nearly indistinguishable from wild-type rates. Interestingly, under diurnal light conditions (12 h of light and 12 h of dark), normal photoautotrophic growth of the mutant is completely restored.

scholarly journals Potential relationship between dietary long-chain saturated fatty acids and hypothalamic dysfunction in obesity

2019 ◽  
Author(s):  
Domenico Sergi ◽  
Lynda M Williams
Keyword(s):  
Fatty Acids ◽  
Molecular Mechanisms ◽  
Saturated Fatty Acids ◽  
Current Evidence ◽  
Hypothalamic Dysfunction ◽  
Lipid Species ◽  
Hypothalamic Inflammation ◽  
Dietary Component ◽  
Refined Carbohydrates ◽  
Long Chain

Abstract Diet-induced hypothalamic inflammation, which leads to hypothalamic dysfunction and a loss of regulation of energy balance, is emerging as a potential driver of obesity. Excessive intake of long-chain saturated fatty acids is held to be the causative dietary component in hypothalamic inflammation. This review summarizes current evidence on the role of long-chain saturated fatty acids in promoting hypothalamic inflammation and the related induction of central insulin and leptin insensitivity. Particularly, the present review focuses on the molecular mechanisms linking long-chain saturated fatty acids and hypothalamic inflammation, emphasizing the metabolic fate of fatty acids and the resulting lipotoxicity, which is a key driver of hypothalamic dysfunction. In conclusion, long-chain saturated fatty acids are key nutrients that promote hypothalamic inflammation and dysfunction by fostering the build-up of lipotoxic lipid species, such as ceramide. Furthermore, when long-chain saturated fatty acids are consumed in combination with high levels of refined carbohydrates, the proinflammatory effects are exacerbated via a mechanism that relies on the formation of advanced glycation end products.

Interrelation between Cyanophycin Synthesis, L-Arginine Catabolism and Photosynthesis in the Cyanobacterium Synechocystis Sp. Strain PCC 6803

2000 ◽  
Vol 55 (11-12) ◽  
pp. 927-942 ◽  
Author(s):  
Dirk Paul Stephan ◽  
Hans Georg Ruppel ◽  
Elfriede K. Pistorius
Keyword(s):  
Relative Concentration ◽  
Nutrient Deficiency ◽  
Phosphate Limitation ◽  
Physiological Changes ◽  
Wild Type ◽  
Synechocystis Pcc 6803 ◽  
N Source ◽  
Arginine Catabolism ◽  
Synechocystis Sp ◽  
Pcc 6803

ʟ Ultrastructural and imm unocytochemical investigations gave evidence that cyanophycin (multi--arginyl-poly-ʟ-aspartate) granules accumulate in the cyanobacterium Synechocystis sp. strain PCC 6803 under nutrient deficient growth conditions, especially under phosphate limitation. Besides nutrient deficiency, growth of Synechocystis PCC 6803 on ʟ-arginine or ʟ-asparagine as sole N-source also led to high increase of cyanophycin synthesis, while growth on the combination of ʟ-arginine or ʟ-asparagine with nitrate only caused minor cyanophycin accum ulation. Growth of Synechocystis PCC 6803 on ʟ-arginine as sole N-source caused substantial morphological and physiological changes, such as severe thylakoid membrane degradation with partial loss of pigments and photosynthetic activity leading to a phenotype almost like that seen under nutrient deficiency. In contrast to the wild type, the PsbO-free Synechocystis PCC 6803 mutant could grow on ʟ-arginine as sole N-source with only minor morphological and physiological changes. Due to its fairly balanced growth, the mutant accumulated only few cyanophycin granules. ʟ-arginine degrading activity (measured as ornithine and ammonium formation) was high in the PsbO-free mutant but not in the wild type when cells were grown on ʟ-arginine as sole N-source. In both cells types the ʟ-arginine degrading activity was high (although in the PsbO-free mutant about twice as high as in wild type), when cells were grown on ʟ-arginine in combination with nitrate, and as expected very low when cells were grown on nitrate as sole N-source. Thus, net cyanophycin accumulation in Synechocystis PCC 6803 is regulated by the relative concentration of ʟ-arginine to the total nitrogen pool, and the intracellular ʟ-arginine concentration is greatly influenced by the activity of the ʟ-arginine degrading enzyme system which in part is regulated by the activity status of photosystem II. These results suggest a complex interrelation between cyanophycin synthesis, ʟ-arginine catabolism , and in addition photosynthesis in Synechocystis PCC 6803.

scholarly journals Reduction of Photoautotrophic Productivity in the Cyanobacterium Synechocystis sp. Strain PCC 6803 by Phycobilisome Antenna Truncation

2012 ◽  
Vol 78 (17) ◽  
pp. 6349-6351 ◽  
Author(s):  
Lawrence E. Page ◽  
Michelle Liberton ◽  
Himadri B. Pakrasi
Keyword(s):  
Light Harvesting ◽  
Wild Type ◽  
Content Type ◽  
Photosynthetic Productivity ◽  
Mutant Strains ◽  
Light Harvesting Antenna ◽  
Culture Productivity ◽  
Synechocystis Sp ◽  
Pcc 6803

ABSTRACTTruncation of the algal light-harvesting antenna is expected to enhance photosynthetic productivity. The wild type and three mutant strains ofSynechocystissp. strain 6803 with a progressively smaller phycobilisome antenna were examined under different light and CO2conditions. Surprisingly, such antenna truncation resulted in decreased whole-culture productivity for this cyanobacterium.

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