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Sorger D - - 2003
Triacylglycerol (TAG) is the major storage component for fatty acids, and thus for energy, in eukaryotic cells. In this mini-review, we describe recent progress that has been made with the yeast Saccharomyces cerevisiae in understanding formation of TAG and its cell biological role. Formation of TAG involves the synthesis of ...
Nanjundan Meera - - 2003
The lung contains two distinct forms of phosphatidic acid phosphatase (PAP). PAP1 is a cytosolic enzyme that is activated through fatty acid-induced translocation to the endoplasmic reticulum, where it converts phosphatidic acid (PA) to diacylglycerol (DAG) for the biosynthesis of phospholipids and neutral lipids. PAP1 is Mg(2+) dependent and sulfhydryl ...
Sugiura Takayuki - - 2002
Lysophosphatidic acid is a multifunctional phospholipid mediator and elicits a variety of biological responses in vitro and in vivo. Evidence is accumulating that lysophosphatidic acid plays important physiological roles in diverse mammalian tissues and cells. In the present study, we first examined whether lysophosphatidic acid is present in human saliva. ...
Araseki Mina - - 2002
Synthesized PCs containing docosahexaenoic acid (DHA), arachidonic acid (AA), linoleic acid (LA), and palmitic acid (PA) at known positions in the glycerol moiety were oxidized in liposomes, bulk, and organic solvent. In bulk and organic solvent, the oxidative stability of PC decreased with increasing degrees of unsaturation. However, the degree ...
Hird Geoffrey S - - 2002
A novel carbohydrate-based phospholipid containing a phosphatidic acid head group, bis-(2,3-lauroyl)-1-methoxy-5-ribo-phosphatidic acid (DLRPA), was synthesized and characterized by 1H NMR, 13C NMR, and 31P NMR. This molecule is an analog of dilauroyl phosphatidic acid (DLPA). The T(m) of DLRPA decreases with increasing pH in a similar pattern to DLPA, as ...
Xu Fred Y - - 2003
We examined the effect of etomoxir treatment on de novo cardiolipin (CL) biosynthesis in H9c2 cardiac myoblast cells. Etomoxir treatment did not affect the activities of the CL biosynthetic and remodeling enzymes but caused a reduction in [1-14C]palmitic acid or [1-14C]oleic acid incorporation into CL. The mechanism was a decrease ...
Shen Ein-Yiao - - 2002
To investigate the basic mechanism of epileptogenecity in children, we undertook a study of application of penicillin (PC) to the brain of an animal model. Different doses of PC were injected into the hippocampus of Spraque-Dawley rats subjected to microdialysis to observe in vivo changes of excitatory amino acid (EAA) ...
Hunt Alan N - - 2002
Deuterated choline-d(9) labelling of IMR-32 cells enabled comparison of the molecular specificities of whole cell and endonuclear phosphatidylcholine synthesis after 96 h polyunsaturated fatty acid supplementation. Surprisingly, while cell phosphatidylcholine synthesis and remodelling reflected a pattern of polyunsaturated fatty acid accretion, the saturated endonuclear phosphatidylcholine pool was only transiently labelled ...
Poveda José A - - 2002
Purified Acetylcholine Receptor (AcChR) from Torpedo has been reconstituted at low (approximately 1:3500) and high (approximately 1:560) protein to phospholipid molar ratios into vesicles containing egg phosphatidylcholine, cholesterol, and different dimyristoyl phospholipids (dimyristoyl phosphatidylcholine, phosphatidylserine, phosphatidylglycerol and phosphatidic acid) as probes to explore the effects of the protein on phospholipid ...
Lin Jiann-Tsyh - - 2002
As part of a program to elucidate castor oil biosynthesis, we have identified 36 molecular species of PC and 35 molecular species of PE isolated from castor microsomes after incubations with [14C]-labeled FA. The six [14C]FA studied were ricinoleate, stearate, oleate, linoleate, linolenate, and palmitate, which were the only FA ...
Wang Xuemin - - 2002
Phospholipase D (PLD) is a family of diverse enzymes that are differentially regulated by Ca(2+), polyphosphoinositides, free fatty acids, G-proteins, N-acylethanolamines, and membrane lipid environments. Two new types of PLDs were identified in the past year: one is activated by oleic acid and the other requires no cation for activity. ...
Nigou Jérôme - - 2002
Recent studies have demonstrated that, during infection of macrophages by mycobacteria, phospholipids (PLs) are released from the mycobacterial cell wall within infected macrophages and transported out of this compartment into intracellular vesicles. The release of these PLs may have functions that influence the outcome of mycobacterial infections. Despite their important ...
Panasenko O M - - 2002
The interaction between unsaturated phosphatidylcholines and either exogenous or endogenous (produced by the enzyme system involving myeloperoxidase (MPO), H2O2, and Cl-) hypochlorite was studied in multilayer liposomes containing oleic, linoleic, and arachidonic acid residues using MALDI-TOF mass spectrometry. At pH 7.4, hypochlorite reacts with the double bond of the oleic ...
Laxalt Ana M - - 2002
Phospholipid-derived molecules are emerging as novel second messengers in plant defence signalling. Recent research has begun to reveal the signals produced by the enzymes phospholipase C, phospholipase D and phospholipase A2 and their putative downstream targets. These include the activation of a MAP kinase cascade and triggering of an oxidative ...
Pillai Manoj G - - 2002
The incorporation of radiolabeled lipid precursors into triacylglycerol (TG) molecular species in Mortierella ramanniana var. angulispora, an oleaginous fungus, was studied to determine the biosynthetic pathways for TG molecular species. Radiolabeled TG molecular species were separated and quantified by reverse-phase high performance liquid chromatography with a radioisotope detector. The major ...
Balsinde Jesús - - 2002
In the present study the lysophospholipid sources for arachidonic (AA) and eicosapentaenoic acid (EPA) incorporation into and redistribution within the phospholipids of phorbol-ester-differentiated U937 cells was investigated. Initially, AA incorporated primarily into choline glycerophospholipids (PC), whereas EPA incorporated mainly into ethanolamine glycerophospholipids (PE). Bromoenol lactone (BEL), an inhibitor of the ...
Lund Eric D - - 2002
Perkinsus marinus is a protozoan parasite that causes high mortality in its commercially and ecologically important host, the Eastern oyster Crassostrea virginica. In order to understand the host-parasite relationship in lipid metabolism, the ability of P. marinus to synthesize phospholipids from polar headgroup precursors was investigated. Pulse/chase experiments were conducted ...
Morales Rogelio - - 2002
The interfacial activation of porcine pancreatic phospholipase A(2) (PLA(2)) during the hydrolysis of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine liposomes at different temperatures has been monitored by fluorescence changes of the 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) lipid derivatives 1-palmitoyl-2-[6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]dodecanoyl]-sn-glycero-3-phosphocholine (C(12)-NBD-PC) and 12-[(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)]dodecanoic acid (C(12)-NBD-FA) inserted in the substrate vesicles. These long-chain monitors, in contrast to the previously used ...
Bigogno Chiara - - 2002
The fresh-water green alga Parietochloris incisa is the richest plant source of the PUFA arachidonic acid (20:4n-6, AA). To elucidate the biosynthesis of AA in this alga we labeled cultures of P. incisa with radioactive precursors. Pulse chase labeling with acetate resulted in its incorporation via the de novo biosynthesis ...
Lindberg Jan - - 2002
New efficient routes to enantiopure phospholipids, starting from (S)-glycidol, are described. Lysophosphatidic acids and phosphatidic acids were obtained in good overall yields from (S)-glycidol, in only three and four steps, respectively. Moreover, the strategy can also be used to produce phosphatidylcholines in three steps. Using dialkylphosphoramidites, (S)-glycidol was phosphorylated to ...
Hoffman D R - - 2001
BACKGROUND: With the increase in commercial vegetable production in greenhouses, occupational sensitization to bumblebee venom is becoming more common. Studies using sera from subjects thus sensitized allow evaluation of the allergenic specificity of bumblebee sensitization. OBJECTIVE: The purposes of this study were to determine the degree of species group specificity ...
Wang C - - 2001
Oleate-dependent phospholipase D (PLD; EC 3.1.4.4) has been reported in animal systems, but its molecular nature is unkown. Multiple PLDs have been characterized in plants, but none of the previously cloned PLDs exhibits the oleate-activated activity. Here, we describe the biochemical and molecular identification and characterization of an oleate-activated PLD ...
Wongkajornsilp A - - 2001
The somatic genetic defect in paroxysmal nocturnal haemoglobinuria (PNH) involves a block in the transfer of GlcNAc from UDP-GlcNAc to phosphatidylinositol (PI), the first step in the biosynthetic pathway for glycosylphosphatidylinositols (GPIs). We asked whether an exogenous lipid corresponding to an early intermediate in this pathway can be taken up ...
Mizuguchi H - - 2001
The mechanism by which p-chlorophenoxyisobutyric acid (clofibric acid) induces striking changes in the proportion of the molecular species of phosphatidylcholine (PC) in rat liver was studied. Treatment of rats with clofibric acid strikingly increased the content of 1-palmitoyl-2-oleoyl (16:0-18:1) PC, but decreased the contents of 1-palmitoyl-2-docosahexaenoyl (16:0-22:6), 1-stearoyl-2-arachidonoyl (18:0-20:4), and ...
Sugiura Shinji - - 2001
The formation of reversed micellar systems composed of phosphatidylcholine (PC) and fatty acid was newly demonstrated by a significant increase in water content in the organic ethyl oleate phase when the micelles were prepared by the contact method. The solubilized water concentration in the reversed micellar organic phase reached 3 ...
Christian Printzen
A taxonomic study of corticolous species of Lecanora in the Sonoran Desert region containing usnic acids and not belonging to Lecanora s. str. is presented. Descriptions, notes on the ecology and distribution and a key to the 17 species recognized within the area are included. Lecanora coniferarum Printzen, L. latens ...
Selishcheva A A - - 2001
Liposomes made from phosphatidylcholine (PC) or PC-fatty acid ester mixtures have been shown to induce an activation of the respiratory burst in human blood monocytes and alveolar macrophages (AM). Incorporation of 1,2-diacylglycerol or arachidonic acid into PC liposomes significantly enhanced the effect. In the case of AM, the effect of ...
Roque M E - - 2001
The synthesis of phosphatidylcholine (PC) in rod outer segments (ROS) catalysed by lysophosphatidylcholine acyltransferase and phosphatidylethanolamine N-methyltransferase (PE N-MTase) was studied and the effects of natural (FA and lysophospholipids) and synthetic (Triton X-100, deoxycholate and CHAPS) surfactants was evaluated. In all experimental conditions used, incorporation of labelled oleate into lysophosphatidylcholine ...
Nomura T - - 2001
Phospholipase A2, which is linked to a protein kinase C pathway, hydrolyzes phosphatidylcholine into cis-unsaturated free fatty acids and lysophosphatidylcholine (lysoPC). The present study investigated the effect of the free fatty acids, such as arachidonic, oleic, linoleic, and linolenic acid, and lysoPC on neurotransmission by monitoring population spikes (PSs) from ...
Sawai T - - 2001
The activity of phospholipase A2 (PLA2) is elevated in the intestinal epithelia of patients with inflammatory bowel disease (IBD). We recently reported that PLA2 mediates hydrolysis of phosphatidylcholine (PC) to lysophosphatidylcholine (L-PC) when both are applied to the apical surface of cultured EC monolayers, resulting in increased bacterial translocation (BT) ...
Munnik T - - 2001
Evidence is accumulating that phosphatidic acid is a second messenger. Its level increases within minutes of a wide variety of stress treatments including ethylene, wounding, pathogen elicitors, osmotic and oxidative stress, and abscisic acid. Enhanced signal levels are rapidly attenuated by phosphorylating phosphatidic acid to diacylglycerol pyrophosphate. Phosphatidic acid is ...
Miao Q - - 2001
The translocation of apocytochrome c (apocyt.c) across large unilamellar vesicles (LUVs) constructed from mixtures of anionic and zwitterionic phospholipids, phosphatidylethanolamine (PE) and phosphatidylcholine (PC), has been studied. It was shown that the import ratio of horse heart apocyt.c in LUVs composed of phosphatidic acid (PA) combined with PE and PC ...
Rao A M - - 2001
Ten min forebrain ischemia/1-day reperfusion resulted in significant decreases in total phosphatidylcholine (PtdCho), phosphatidylinositol (PtdIns), and cardiolipin in gerbil hippocampus. CDP-choline restored cardiolipin levels, arachidonic acid content of PtdCho, partially but significantly restored total PtdCho, and had no effect on PtdIns. These data suggest that CDP-choline prevented the activation of ...
Kearns D B - - 2001
The lipid phosphatidylethanolamine (PE) is the first chemoattractant to be described for a surface-motile bacterium. In Myxococcus xanthus, the specific activity of PE is determined by its fatty acid components. Two active species have been identified: dilauroyl PE and dioleoyl PE. Excitation to dilauroyl PE requires fibril appendages and the ...
Tappia P S - - 2001
The cardiac sarcolemmal membrane cis -unsaturated fatty acid-sensitive phospholipase D hydrolyzes phosphatidylcholine to form phosphatidic acid. The functional significance of phosphatidic acid is indicated by its ability to increase [Ca(2+)](i)and augment cardiac contractile performance via the activation of phospholipase C. Accordingly, we tested the hypothesis that a defect occurs in ...
Ves-Losada A - - 2001
Liver nuclear incorporation of stearic (18:0), linoleic (18:2n-6), and arachidonic (20:4n-6) acids was studied by incubation in vitro of the [1-14C] fatty acids with nuclei, with or without the cytosol fraction at different times. The [1-14C] fatty acids were incorporated into the nuclei as free fatty acids in the following ...
Zien C A - - 2001
The common plant phospholipase D (PLD), PLDalpha, has been proposed to be involved in wound-induced production of jasmonic acid. To better understand the role(s) of PLDalpha in the wound response, detailed lipid analysis was carried out to determine the in vivo substrates and the contribution of PLDalpha in wound-induced lipid ...
Sultan A - - 2001
An assortment of agents can induce mitochondria to undergo a permeability transition, which results in the inner mitochondrial membrane becoming nonselectively permeable to small (<1500 Da) solutes. This mitochondrial permeability transition (MPT) is characterized by a strict dependence on matrix Ca2+ and sensitivity to cyclosporin A (CsA). However, it is ...
Lee W H - - 2001
Asp49 plays a fundamental role in supporting catalysis by phospholipases A2 by coordinating the calcium ion which aids in the stabilization of the tetrahedral intermediate. In several myotoxins from the venoms of Viperidae snakes, this aspartic acid is substituted by lysine. The loss of calcium binding capacity by these mutants ...
Gangar A - - 2001
Triacylglycerol is one of the major storage forms of metabolic energy in eukaryotic cells. Biosynthesis of triacylglycerol is known to occur in membranes. We report here the isolation, purification, and characterization of a catalytically active cytosolic 10 S multienzyme complex for triacylglycerol biosynthesis from Rhodotorula glutinis during exponential growth. The ...
Schmidt R - - 2001
Impairment of alveolar surfactant function has been documented in the acute respiratory distress syndrome (ARDS) and in severe pneumonia (PNEU); however, the underlying mechanisms are not completely understood. In the current report we present a detailed analysis of fatty acid (FA) profiles of different surfactant phospholipid (PL) classes isolated from ...
Grandbois M - - 2000
Polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) was used to follow the hydrolysis of phospholipid monolayers at the air-water interface by phospholipase A2 (PLA2). The decrease in the intensity of the nuC=O ester band of dipalmitoylphosphatidylcholine at 1733 cm(-1) and the appearance of two new infrared bands in the 1530-1580 cm(-1) ...
Chatrattanakunchai S - - 2000
Microsomal membrane preparations from Mortierella alpina catalysed the conversion of sn-glycerol 3-phosphate and [(14)C]oleoyl-CoA to radioactive phosphatidic acid, diacylglycerol and triacylglycerol. Experiments with lysophosphatidic acid and [(14)C]oleoyl-CoA gave a similar pattern of radioactivity in the complex lipids. The specific activity of lysophosphatidate acyltransferase was almost eight times greater than sn-glycerol-3-phosphate ...
Morrill G A - - 2000
Progesterone, the physiological inducer of amphibian meiosis, acts within minutes at plasma membrane receptors of the Rana pipiens oocyte to release 1,2-diacylglycerol (DAG) from plasma and intracellular membranes. High-performance liquid chromatography (HPLC) analysis of lipid extracts of uninduced oocytes indicates the presence of at least three classes of DAG with ...
Sarri E - - 2000
We have studied phospholipase D activation in [(32)P]orthophosphoric acid-prelabeled rat pancreatic acini by measuring the formation of (32)P-phosphatidylalcohols as stimulated in the presence of ethanol or butanol. A small but significant and time-dependent basal accumulation of [(32)P]phosphatidylethanol and [(32)P]phosphatidylbutanol was detected, which was further stimulated by phorbol myristate acetate, orthovanadate ...
Banaƛ A - - 2000
We have characterized three CoA-independent types of enzyme, phospholipases, phospholipid:diacylglycerol acyltransferases (PDATs) and cholinephosphotransferases, responsible for the removal of unusual fatty acids from phosphatidylcholine (PC) in microsomal preparations from developing oil seeds. The metabolism of sn-2-[(14)C]acyl-PC was monitored in microsomal preparations from various oilseeds having either medium-chain, acetylenic, epoxy or ...
Fraser T - - 2000
Microsomal membrane preparations from the developing seeds of sunflower (Helianthus annuus L.) catalyse the conversion of sn-glycerol-3-phosphate and acyl-CoA to triacylglycerol via phosphatidic acid and diacylglycerol. The formation of diacylglycerol from phosphatidic acid was Mg2+ dependent and in the presence of EDTA phosphatidic acid accumulated. This property was used to ...
Canavoso L E - - 2000
The pathway for the synthesis of diacylglycerol in larval Manduca sexta midgut was studied. Fifth instar larvae were fed with [9, 10-(3)H]-oleic acid-labeled triolein and the incorporation of the label into lipid intermediates was analyzed as a function of time. The results showed that the triacylglycerol was hydrolyzed to fatty ...
Granier L A - - 2000
BACKGROUND: Neuronal ceroid lipofuscinosis (NCL) is a relatively common group of inherited neurodegenerative disorders characterised by the accumulation of autofluorescent lipopigments (ceroid) similar to lipofuscin. Because of this property, studies have concentrated on fatty acid metabolism and lipid peroxidation. METHODS: In the present study, the fatty acid composition of phosphatidylcholine ...
Rusnak A - - 2000
The incorporation of [1-14C]palmitic or [1-14C]oleic acid into phosphatidylcholine and the effect on blood group antigen expression were examined in human erythrocytes stored at 4 degrees C for 0-3 weeks. Blood drawn into EDTA was obtained by venepuncture from healthy volunteers. A 50% suspension of washed erythrocytes was incubated in ...
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