Diatoms and Plants Acyl-CoA:lysophosphatidylcholine Acyltransferases (LPCATs) Exhibit Diverse Substrate Specificity and Biochemical Properties

The search of the Phaeodactylum tricornutum genome database revealed the existence of six genes potentially encoding lysophospholipid acyltransferases. One of these genes, Phatr3_J20460, after introduction to yeast ale1 mutant disrupted in the LPCAT gene, produced a very active acyl-CoA:lysophosphatidylcholine (LPCAT) enzyme. Using in vitro assays applying different radioactive and non-radioactive substrates and microsomal fractions from such yeast, we have characterized the biochemical properties and substrate specificities of this PtLPCAT1. We have found that the substrate specificity of this enzyme indicates that it can completely supply phosphatidylcholine (PC) with all fatty acids connected with a biosynthetic pathway of very long-chain polyunsaturated fatty acids (VLC-PUFAs) used further for the desaturation process. Additionally, we have shown that biochemical properties of the PtLPCAT1 in comparison to plant LPCATs are in some cases similar (such as the dependency of its activity on pH value), differ moderately (such as in response to temperature changes), or express completely different properties (such as in reaction to calcium and magnesium ions or toward some acyl-CoA with 20C polyunsaturated fatty acids). Moreover, the obtained results suggest that cloned “Phatr3_J20460” gene can be useful in oilseeds plant engineering toward efficient production of VLC-PUFA as LPCAT it encodes can (contrary to plant LPCATs) introduce 20:4-CoA (n-3) to PC for further desaturation to 20:5 (EPA, eicosapentaenoic acid).

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Phytophthora infestans Cholinephosphotransferase with Substrate Specificity for Very-Long-Chain Polyunsaturated Fatty Acids

Applied and Environmental Microbiology ◽

10.1128/aem.03250-12 ◽

2012 ◽

Vol 79 (5) ◽

pp. 1573-1579 ◽

Cited By ~ 4

Author(s):

Yan Chen ◽

Hsiang-yun Chi ◽

Dauenpen Meesapyodsuk ◽

Xiao Qiu

Keyword(s):

Fatty Acids ◽

Substrate Specificity ◽

Polyunsaturated Fatty Acids ◽

Phytophthora Infestans ◽

Neutral Lipids ◽

Amino Acid Identity ◽

Pcr Analysis ◽

Content Type ◽

Long Chain

ABSTRACTThe effective flux between phospholipids and neutral lipids is critical for a high level of biosynthesis and accumulation of very-long-chain polyunsaturated fatty acids (VLCPUFAs), such as arachidonic acid (ARA; 20:4n-6), eicosapentaenoic acid (EPA; 20:5n-3), and docosahexaenoic acid (DHA; 22:6n-3). Here we describe a cDNA (PiCPT1) fromPhytophthora infestans, a VLCPUFA-producing oomycete, that may have a role in acyl trafficking between diacylglycerol (DAG) and phosphatidylcholine (PC) during the biosynthesis of VLCPUFAs. The cDNA encodes a polypeptide of 393 amino acids with a conserved CDP-alcohol phosphotransferase motif and approximately 27% amino acid identity to theSaccharomyces cerevisiaecholinephosphotransferase (ScCPT1).In vitroassays indicate that PiCPT1 has high cholinephosphotransferase (CPT) activity but no ethanolaminephosphotransferase (EPT) activity. Substrate specificity assays show that it prefers VLCPUFA-containing DAGs, such as ARA DAG and DHA DAG, as substrates. Real-time PCR analysis reveals that expression ofPiCPT1was upregulated inP. infestansorganisms fed with exogenous VLCPUFAs. These results lead us to conclude that PiCPT1 is a VLCPUFA-specific CPT which may play an important role in shuffling VLCPUFAs from DAG to PC in the biosynthesis of VLCPUFAs inP. infestans.

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Functional Analysis of an Acyltransferase-Like Domain from Polyunsaturated Fatty Acid Synthase in Thraustochytrium

Microorganisms ◽

10.3390/microorganisms9030626 ◽

2021 ◽

Vol 9 (3) ◽

pp. 626

Author(s):

Carla Almendáriz-Palacios ◽

Dauenpen Meesapyodsuk ◽

Xiao Qiu

Keyword(s):

Fatty Acids ◽

Polyunsaturated Fatty Acids ◽

Free Fatty Acids ◽

Fatty Acid Synthase ◽

Site Directed Mutagenesis ◽

In Vitro Assays ◽

Complementation Test ◽

Temperature Sensitive ◽

Synthetase Activity

Biosynthesis of very long chain polyunsaturated fatty acids (VLCPUFA) such as docosahexaenoic acid (DHA, 22:6-4,7,10,13,16,19) and docosapentaenoic acid (DPA, 22:5-4,7,10,13,16) in protist Thraustochytrium is catalyzed by a polyunsaturated fatty acids (PUFA) synthase comprising three large subunits, each with multiple catalytic domains. This study used complementation test, in vitro assays, and functional expression to characterize an acyltransferase (AT)-like domain in Subunit-B of a PUFA synthase from Thraustochytrium. Complementation test in Escherichia coli showed that the AT-like domain could not restore the growth phenotype of a temperature-sensitive mutant (∆fabDts) defective in malonyl-CoA:ACP transacylase activity. In vitro assays showed that the AT-like domain possessed thioesterase activity towards a few acyl-CoAs tested where docosahexaenoyl-CoA (DHA-CoA) was the preferred substrate. Expression of this domain in an E. coli mutant (∆fadD) defective in acyl-CoA synthetase activity resulted in the increased accumulation of free fatty acids. Site-directed mutagenesis showed that the substitution of two putative active site residues, serine at 96 (S96) and histidine at 220 (H220), in the AT-like domain significantly reduced its activity towards DHA-CoA and accumulation of free fatty acids in the ∆fadD mutant. These results indicate that the AT-like domain of the PUFA synthase does not function as a malonyl-CoA:ACP transacylase, rather it functions as a thioesterase. It might catalyze the last step of the VLCPUFA biosynthesis by releasing freshly synthesized VLCPUFAs attached to ACP domains of the PUFA synthase in Thraustochytrium.

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N-3 Polyunsaturated Fatty Acids Modulate In-Vitro T Cell Function in Type I Diabetic Patients

Lipids ◽

10.1007/s11745-008-3176-3 ◽

2008 ◽

Vol 43 (6) ◽

pp. 485-497 ◽

Cited By ~ 9

Author(s):

Sid Ahmed Merzouk ◽

Meriem Saker ◽

Karima Briksi Reguig ◽

Nassima Soulimane ◽

Hafida Merzouk ◽

...

Keyword(s):

Fatty Acids ◽

T Cell ◽

Polyunsaturated Fatty Acids ◽

Cell Function ◽

Diabetic Patients ◽

Type I ◽

T Cell Function

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n‐3 polyunsaturated fatty acids provoke a specific transcriptional profile in rabbit adipose‐derived stem cells in vitro

Journal of Animal Physiology and Animal Nutrition ◽

10.1111/jpn.13075 ◽

2019 ◽

Vol 103 (3) ◽

pp. 925-934

Author(s):

Eкaterina Vackova ◽

Darko Bosnakovski ◽

Bodil Bjørndal ◽

Penka Yonkova ◽

Natalia Grigorova ◽

...

Keyword(s):

Fatty Acids ◽

Stem Cells ◽

Polyunsaturated Fatty Acids ◽

Transcriptional Profile ◽

Adipose Derived Stem Cells

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Quantification of Volatile Aldehydes Deriving from In Vitro Lipid Peroxidation in the Breath of Ventilated Patients

Molecules ◽

10.3390/molecules26113089 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3089

Author(s):

Lukas M. Müller-Wirtz ◽

Daniel Kiefer ◽

Sven Ruffing ◽

Timo Brausch ◽

Tobias Hüppe ◽

...

Keyword(s):

Lipid Peroxidation ◽

Fatty Acids ◽

Polyunsaturated Fatty Acids ◽

Breathing Circuit ◽

Aliphatic Aldehydes ◽

Mechanically Ventilated ◽

Non Invasive ◽

Plastic Parts ◽

Ventilated Patients

Exhaled aliphatic aldehydes were proposed as non-invasive biomarkers to detect increased lipid peroxidation in various diseases. As a prelude to clinical application of the multicapillary column–ion mobility spectrometry for the evaluation of aldehyde exhalation, we, therefore: (1) identified the most abundant volatile aliphatic aldehydes originating from in vitro oxidation of various polyunsaturated fatty acids; (2) evaluated emittance of aldehydes from plastic parts of the breathing circuit; (3) conducted a pilot study for in vivo quantification of exhaled aldehydes in mechanically ventilated patients. Pentanal, hexanal, heptanal, and nonanal were quantifiable in the headspace of oxidizing polyunsaturated fatty acids, with pentanal and hexanal predominating. Plastic parts of the breathing circuit emitted hexanal, octanal, nonanal, and decanal, whereby nonanal and decanal were ubiquitous and pentanal or heptanal not being detected. Only pentanal was quantifiable in breath of mechanically ventilated surgical patients with a mean exhaled concentration of 13 ± 5 ppb. An explorative analysis suggested that pentanal exhalation is associated with mechanical power—a measure for the invasiveness of mechanical ventilation. In conclusion, exhaled pentanal is a promising non-invasive biomarker for lipid peroxidation inducing pathologies, and should be evaluated in future clinical studies, particularly for detection of lung injury.

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Utilization of polyunsaturated fatty acids by human diploid cells aging in vitro

Lipids ◽

10.1007/bf02534065 ◽

1980 ◽

Vol 15 (6) ◽

pp. 412-420 ◽

Cited By ~ 15

Author(s):

Robert D. Lynch

Keyword(s):

Fatty Acids ◽

Polyunsaturated Fatty Acids ◽

Human Diploid Cells ◽

Diploid Cells

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Host/Malassezia Interaction: A Quantitative, Non-Invasive Method Profiling Oxylipin Production Associates Human Skin Eicosanoids with Malassezia

Metabolites ◽

10.3390/metabo11100700 ◽

2021 ◽

Vol 11 (10) ◽

pp. 700

Author(s):

Yohannes Abere Ambaw ◽

Martin P. Pagac ◽

Antony S. Irudayaswamy ◽

Manfred Raida ◽

Anne K. Bendt ◽

...

Keyword(s):

Fatty Acids ◽

Immune System ◽

Polyunsaturated Fatty Acids ◽

Human Skin ◽

Skin Surface ◽

Lipid Mediators ◽

Dependent Manner ◽

Human Immune System ◽

Plant Host

Malassezia are common components of human skin, and as the dominant human skin eukaryotic microbe, they take part in complex microbe–host interactions. Other phylogenetically related fungi (including within Ustilagomycotina) communicate with their plant host through bioactive oxygenated polyunsaturated fatty acids, generally known as oxylipins, by regulating the plant immune system to increase their virulence. Oxylipins are similar in structure and function to human eicosanoids, which modulate the human immune system. This study reports the development of a highly sensitive mass-spectrometry-based method to capture and quantify bioactive oxygenated polyunsaturated fatty acids from the human skin surface and in vitro Malassezia cultures. It confirms that Malassezia are capable of synthesizing eicosanoid-like lipid mediators in vitro in a species dependent manner, many of which are found on human skin. This method enables sensitive identification and quantification of bioactive lipid mediators from human skin that may be derived from metabolic pathways shared between skin and its microbial residents. This enables better cross-disciplinary and detailed studies to dissect the interaction between Malassezia and human skin, and to identify potential intervention points to promote or abrogate inflammation and to improve human skin health.

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Micropropagation of Achillea millefolium L. on half-strength ms medium and direct rooting and acclimatization of microshoots in hydroponic culture

Glasnik Sumarskog fakulteta ◽

10.2298/gsf1511099m ◽

2015 ◽

pp. 99-112

Author(s):

Marija Markovic ◽

Dragana Skocajic ◽

Mihailo Grbic ◽

Matilda Djukic ◽

Dragica Obratov-Petkovic ◽

...

Keyword(s):

Medicinal Plant ◽

Nutrient Solution ◽

Ph Value ◽

Ex Vitro Rooting ◽

In Vitro Rooting ◽

Efficient Production ◽

Ms Medium ◽

Ex Vitro ◽

Half Strength

The aim of this study was to determine the possibility of micropropagation of the medicinal plant A. millefolium on half-strength MS medium and ex vitro rooting and acclimatization of the obtained microshoots in hydroculture in order to establish an efficient production method. Two explant types were used: basal and terminal cuttings, and better results were achieved when terminal cuttings were used. The development of shoots in the multiplication phase was successful with a regeneration percentage of 100%. Ex vitro rooting in a modified Hoagland nutrient solution was successful (83%), but the percentage of in vitro rooting on half-strength MS medium without hormones was higher (95%). However, bearing in mind that mass production of A. millefolium is more efficient when the phase of in vitro rooting is excluded, this method could be recommended for commercial propagation of this medicinal plant. It is necessary to conduct additional research in order to optimize the composition, EC and pH value of the hydroponic nutrient solution.

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