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Malanovic Nermina N Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50/II, Graz, - - 2008
In eukaryotes, S-adenosyl-L-homocysteine hydrolase (Sah1) offers a single way for degradation of S-adenosyl-L-homocysteine, a product and potent competitive inhibitor of S-adenosyl-L-methionine (AdoMet)-dependent methyltransferases. De novo phosphatidylcholine (PC) synthesis requires three AdoMet-dependent methylation steps. Here we show that down-regulation of SAH1 expression in yeast leads to accumulation of S-adenosyl-L-homocysteine and decreased ...
Di Venosa Gabriela - - 2008
Liposomes of different compositions have been designed to improve delivery of aminolevulinic acid (ALA) and its esterified derivatives ALA-Hexyl ester (He-ALA) and ALA-Undecanoyl ester (Und-ALA) for its use in photodynamic therapy (PDT). Egg yolk phosphatidyl choline (PC), phosphatidic acid (PA) and phosphatidyl glycerol (PG) were employed in the preparation of ...
Miller Rhea M - - 2008
Pseudomonas aeruginosa demonstrates type IV pilus-mediated directional twitching motility up a gradient of phosphatidylethanolamine (PE). Only one of four extracellular phospholipases C of P. aeruginosa (i.e., PlcB), while not required for twitching motility per se, is required for twitching-mediated migration up a gradient of PE or phosphatidylcholine. Whether other lipid ...
Scapa Erez F EF Department of Medicine, Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, - - 2008
Phosphatidylcholine transfer protein (PC-TP, also known as StarD2) is a highly specific intracellular lipid binding protein with accentuated expression in oxidative tissues. Here we show that decreased plasma concentrations of glucose and free fatty acids in fasting PC-TP-deficient (Pctp(-/-)) mice are attributable to increased hepatic insulin sensitivity. In hyperinsulinemic-euglycemic clamp ...
Ushida Yusuke - - 2008
The aim of this study was to point out the potential of tartary buckwheat on vascular functions. A nonabsorbed fraction of hot-water extract of tartary buckwheat on a SP70 column (TBSP-T), which was free from rutin, was used for this aim. In a contractile experiment using Sprague-Dawley rat thoracic aorta ...
Pruitt Nancy L - - 2008
Abstract Third-instar larvae of the goldenrod gall fly Eurosta solidaginis (Diptera: Tephritidae) are freeze tolerant in winter. During freezing, cell membranes must compensate for both low temperature and partial dehydration. Documented adaptations to low temperature include increased fatty acid unsaturation and enrichment of cone-shaped phosphatides, both of which inhibit formation ...
Ghosh Ananda K - - 2008
One of the major determinants of organic solvent tolerance is the increase in membrane phospholipids. Here we report for the first time that an increase in the synthesis of phosphatidic acid is responsible for enhanced phospholipid synthesis that confers tolerance to the organic solvent in Saccharomyces cerevisiae. This increase in ...
Zhao Yang - - 2008
Phosphatidylcholine (PC) is synthesized through the Kennedy pathway, but more than 50% of PC is remodeled through the Lands cycle, i.e. the deacylation and reacylation of PC to attain the final and proper fatty acids within PC. The reacylation step is catalyzed by lysophosphatidylcholine acyltransferase (LPCAT), and we report here ...
Zhang Xu Hannah - - 2007
The G1 phase of the cell cycle is marked by the rapid turnover of phospholipids. This turnover is regulated by CTP:phosphocholine-cytidylyltransferase (CCT) and group VIA Ca(2+)-independent-phospholipase A(2) (iPLA(2)). We previously reported that inhibition of iPLA(2) arrests cells in G1 phase of the cell cycle by activating the p53-p21 checkpoint. Here ...
Nakamura Yuki - - 2007
The origin of diacylglycerol, a substrate for membrane lipid biosynthesis, is not fully understood. Here, we report that Petunia hybrida floral organs contain large amounts of diacylglycerol. Our data suggest that in stamens and pistils diacylglycerol is supplied both from phosphatidylcholine by non-specific phospholipase C activity and de novo via ...
Boeris P S - - 2007
AIMS: The aim of this work was to establish if the response to tetradecyltrimethylammonium (TDTMA), a representative quaternary ammonium compound (QAC), involves changes in the phospholipid (PL) composition of Pseudomonas putida A ATCC 12633. METHODS AND RESULTS: Pseudomonas putida was exposed to 50 mg l(-1) of TDTMA for 15 min, ...
Bates Philip D - - 2007
In expanding pea leaves, over 95% of fatty acids (FA) synthesized in the plastid are exported for assembly of eukaryotic glycerolipids. It is often assumed that the major products of plastid FA synthesis (18:1 and 16:0) are first incorporated into 16:0/18:1 and 18:1/18:1 molecular species of phosphatidic acid (PA), which ...
Benghezal Mohammed - - 2007
Phosphatidic acid is the intermediate, from which all glycerophospholipids are synthesized. In yeast, it is generated from lysophosphatidic acid, which is acylated by Slc1p, an sn-2-specific, acyl-coenzyme A-dependent 1-acylglycerol-3-phosphate O-acyltransferase. Deletion of SLC1 is not lethal and does not eliminate all microsomal 1-acylglycerol-3-phosphate O-acyltransferase activity, suggesting that an additional enzyme ...
Bleijerveld Onno B - - 2007
In mammalian cells, phosphatidylethanolamine (PtdEtn) is mainly synthesized via the CDP-ethanolamine (Kennedy) pathway and by decarboxylation of phosphatidylserine (PtdSer). However, the extent to which these two pathways contribute to overall PtdEtn synthesis both quantitatively and qualitatively is still not clear. To assess their contributions, PtdEtn species synthesized by the two ...
Zarei Kobra - - 2007
A very sensitive, simple and selective spectrophotometric method for simultaneous determination of phosphate and silicate based on formation of phospho- and silicomolybdenum blue complexes in the presence of ascorbic acid is described. Although the complexes of phosphate and silicate with reagent in the presence of ascorbic acid show a spectral ...
Panasenko Oleg M - - 2007
The leukocyte enzyme myeloperoxidase (MPO) is capable of catalyzing the oxidation of chloride and bromide ions, at physiological concentrations of these substrates, by hydrogen peroxide, generating hypochlorous acid (HOCl) and hypobromous acid (HOBr), respectively. Our previous results showed that the hypohalous acids formed react with double bonds in phosphatidylcholines (PCs) ...
Russo Marco Antonio - - 2007
In a long-term experiment bean (Phaseolus vulgaris L.) seedlings were grown for 18 days in hydroponics in either phosphate-sufficient (+P) or phosphate-deficient (-P) nutrient solutions. Phosphate deprivation halved the phosphorous content of roots. In plasma membrane (PM) fractions isolated from -P roots the phospholipid (PL) level was reduced from 35 ...
Handwerger Rachel G RG Institute for Medicine and Engineering, 1024 Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, - - 2007
A biotinylated photocleavable polyethylenimine (B-PC-PEI) was designed and synthesized for the capture and controlled release of nucleic acids from solid supports. B-PC-PEI was synthesized via a three-step reaction process and verified by 1H NMR and mass spectrometry. In aqueous solution, the o-nitrobenzyl group within B-PC-PEI was efficiently cleaved by 5 ...
Lin Jiann-Tsyh - - 2007
HPLC fractions of diricinoleoylacylglycerols containing one non-ricinoleoyl chain from castor oil were used to identify the regiospecific location of this non-ricinoleoyl chain on the glycerol backbone using electrospray ionization-MS3 of lithium adducts. The regiospecific ions used were from the loss of alpha,beta-unsaturated fatty acid specific at the sn-2 position. The ...
Megighian Aram - - 2007
The study of the effect of snake presynaptic neurotoxins with phospholipase A2 activity on nerve terminals has recently unveiled the inhibitory action of a lysophosphatidylcholine (LysoPC)/fatty acid mixture. We report here that these neurotoxins have no activity on Drosophila melanogaster nerve terminals. However, a 1:1 mixture of LysoPC and oleic ...
Rakotomanga M - - 2007
Miltefosine (hexadecylphosphocholine [HePC]) is the first orally active antileishmanial drug. Transient HePC treatment of Leishmania donovani promastigotes at 10 microM significantly reduced the phosphatidylcholine content and enhanced the phosphatidylethanolamine (PE) content in parasite membranes, suggesting a partial inactivation of PE-N-methyltransferase. Phospholipase D activity did not seem to be affected by ...
Adamczyk Agata - - 2007
In the present study we investigated the role of alpha-synuclein (ASN) and its fragment NAC in arachidonic acid (AA) turnover in the rat brain. Our data indicated that ASN (10 microM) inhibited [3H]AA incorporation into phosphatidylethanolamine (PE), phosphatidylcholine (PC) and phosphatidylserine (PS) together with phosphatidic acid (PA) by 13%, 27% ...
Fritz Markus - - 2007
Plastidial glycolipids contain diacylglycerol (DAG) moieties, which are either synthesized in the plastids (prokaryotic lipids) or originate in the extraplastidial compartment (eukaryotic lipids) necessitating their transfer into plastids. In contrast, the only phospholipid in plastids, phosphatidylglycerol (PG), contains exclusively prokaryotic DAG backbones. PG contributes in several ways to the functions ...
Singh Dev K - - 2007
We previously showed that group V secretory phospholipase A(2) (sPLA(2)V) is inhibited by sphingomyelin (SM), but activated by ceramide. Here, we investigated the effect of sphingolipid structure on the activity and acyl specificity of sPLA(2)V. Degradation of HDL SM to ceramide, but not to ceramide phosphate, stimulated the activity by ...
Caccin Paola - - 2006
Lysophosphatidylcholine rapidly paralyses the neuromuscular junction (NMJ), similarly to snake phospholipase A2 neurotoxins, implicating a lipid hemifusion-pore transition in neuroexocytosis. The mode and kinetics of NMJ paralysis of different lysophospholipids (lysoPLs) in high or low [Mg2+] was investigated. The following order of potency was found: lysophosphatidylcholine>lysophosphatidylethanolamine>lysophosphatidic acid>lysophosphatidylserine>lysophosphatidylglycerol. The latter two ...
Oxley Anthony - - 2007
Pathways of lipid resynthesis in the intestine of fish are relatively unknown. Various reports have suggested the existence of both sn-1,3-specific (pancreatic) and non-specific (bile salt-activated) lipase activity operating on dietary triacylglycerol (TAG) in the intestinal lumen of fish during digestion. Thus, sn-2-monoacylglycerol (2-MAG) and glycerol, respective hydrolytic products of ...
Cho In Hee - - 2007
Metabolomic analysis of raw and cooked pine-mushrooms (Tricholoma matsutake Sing.) of different grades was performed using (1)H nuclear magnetic resonance (NMR) spectrometry and principal component analysis (PCA). PCA of the (1)H NMR spectra of aqueous fractions allowed different grades of raw pine-mushroom to be discriminated by a combination of principal ...
Mulder Anke M - - 2006
Lipid transmitters are tightly regulated by a balance of biosynthetic and degradative enzymes. Termination of the activity of the N-acyl ethanolamine (NAE) class of lipid-signaling molecules, including the endocannabinoid anandamide (AEA), is principally mediated by the integral membrane enzyme fatty acid amide hydrolase (FAAH) in vivo. FAAH(-/-) mice are highly ...
Yin Jun-Jie - - 2006
Conjugated linoleic acids (CLAs) are a group of octadecadienoic acids (18:2) that are naturally present in food products and may have beneficial health effects. Liposomes and ethanol solutions were prepared by mixing synthetic phosphatidylcholines (PCs) with c9,t11-CLA, t10,c12-CLA, and linoleic acid (LA) in the sn-2 position into natural PCs from ...
Andersson Erik - - 2006
15-lipoxygenase-1 (15-LO-1) can oxygenate both free fatty acids and fatty acids bound to membrane phospholipids. The regulation of the activity of membrane associated 15-LO-1 is poorly understood. Here we demonstrate that calcium ionophore stimulates the translocation of 15-LO-1 to the plasma membrane in human dendritic cells. In a protein-lipid overlay ...
Murthy S N Prasanna - - 2006
This paper uses phospholipase Cepsilon as a model to demonstrate that lipids can act as ligands to bind to specific motifs and regulate protein activity via allosteric effects. Phospholipids such as phosphatidic acid and free fatty acids such as arachidonate are potent activators of PLCepsilon, increasing the rate of PI ...
Cazzolli Rosanna - - 2006
Phospholipase D (PLD) hydrolyzes the phosphodiester bond of the predominant membrane phospholipid, phosphatidylcholine producing phosphatidic acid and free choline. This activity can participate in signal transduction pathways and impact on vesicle trafficking for secretion and endocytosis, as well as receptor signalling. Phospholipids can regulate PLD activity directly, through specific intermolecular ...
Yoneyama Kelly A G - - 2006
Detergent-resistant membranes (DRMs) from Leishmania (Viannia) braziliensis promastigotes, insoluble in 1% Triton X-100 at 4 degrees C, were fractionated by sucrose density gradient ultracentrifugation. They were composed of glycoinositolphospholipids (GIPLs), inositol phosphorylceramide (IPC), phosphatidylinositol (PI), phosphatidylethanolamine (PE), and sterols. In contrast, 1% Triton X-100-soluble fraction was composed of PE, phosphatidylcholine, ...
Ghosh Moumita - - 2006
The Group IV phospholipase A2 family is comprised of six intracellular enzymes commonly called cytosolic phospholipase A2 (cPLA2) alpha, cPLA2beta, cPLA2gamma, cPLA2delta, cPLA2epsilon and cPLA2zeta. They are most homologous to phospholipase A and phospholipase B/lysophospholipases of filamentous fungi particularly in regions containing conserved residues involved in catalysis. However, a number ...
Subbaiah Papasani V - - 2006
Sphingomyelin (SM), the second most abundant phospholipid in plasma lipoproteins, was previously shown to be a physiological inhibitor of the lecithin-cholesterol acyltransferase (LCAT) reaction. In this study, we investigated the effects of its metabolites, ceramide and ceramide phosphate, on the activity and fatty acid specificity of LCAT in vitro. Treatment ...
Jitrapakdee S - - 2006
Pyruvate carboxylase (PC) catalyzes the ATP-dependent carboxylation of pyruvate to oxaloacetate. PC serves an anaplerotic role for the tricarboxylic acid cycle, when intermediates are removed for different biosynthetic purposes. In liver and kidney, PC provides oxaloacetate for gluconeogenesis. In adipocytes PC is involved in de novo fatty acid synthesis and ...
Seo Ho Seong - - 2006
Bacterial lipoteichoic acid (LTA) shares a structural motif with platelet-activating factor (PAF). Both molecules are strong inflammatory agents and have a glycerol backbone with two lipid chains at the sn-1 and sn-2 positions. PAF is normally inactivated by PAF-acetylhydrolase (PAF-AH), a phospholipase A2 (PLA2), which removes a short acyl group ...
Mazie Abigail R - - 2006
Phospholipase D catalyzes the hydrolysis of phosphatidylcholine to generate phosphatidic acid, and there is currently much interest in elucidating messenger functions for this molecule. We report here that wounding sheets of corneal epithelial and Madin Darby canine kidney cells induces strong activation of phospholipase D, and we provide evidence that ...
Strokin M - - 2006
Polyunsaturated fatty acids play an important role in the development of pathological states in brain after hypoxia/ischemia. Here, we investigated the role of docosahexaenoic acid (22:6n-3) in brain phospholipids for neuronal survival. We used organotypic cultures of rat brain hippocampal slices exposed to 40 min of oxygen-glucose deprivation, to study ...
Patel Anamika - - 2006
The antioxidant activity of C-Phycocyanin (C-PC) isolated from three cyanobacterial species Lyngbya (marine), Phormidium (marine) and Spirulina (fresh water) was studied in vitro. The results demonstrate that C-PCs from Lyngbya, Phormidium and Spirulina spp. are able to scavenge peroxyl radicals (determined by crocin bleaching assay) with relative rate constant ratio ...
Kooijman Edgar E - - 2005
Phosphatidic acid and lysophosphatidic acid are minor but important anionic bioactive lipids involved in a number of key cellular processes, yet these molecules have a simple phosphate headgroup. To find out what is so special about these lipids, we determined the ionization behavior of phosphatidic acid (PA) and lysophosphatidic acid ...
Wright Christine S CS Department of Pharmacology, X-ray Crystallography Laboratory, University of Virginia, Charlottesville, Virginia 22908-0735, USA. - - 2005
GM2-activator protein (GM2AP) is a lysosomal lipid transfer protein with important biological roles in ganglioside catabolism, phospholipid metabolism, and T-cell activation. Previous studies of crystal structures of GM2AP complexed with the physiological ligand GM2 and platelet activating factor (PAF) have shown binding at two specific locations within the spacious apolar ...
Jenkins G M - - 2005
Phospholipase D (PLD) hydrolyzes the phosphodiester bond of the glycerolipid phosphatidylcholine, resulting in the production of phosphatidic acid and free choline. Phosphatidic acid is widely considered to be the intracellular lipid mediator of many of the biological functions attributed to PLD. However, phosphatidic acid is a tightly regulated lipid in ...
Ichihara Ken'ichi - - 2005
An improved safe method that does not contaminate the environment with cadmium chloride, a toxic heavy metal salt, was developed for the synthesis of phosphatidylcholine (PC). PC was synthesized from sn-glycero-3-phosphocholine (GPC) and fatty acid in one step under mild conditions without the use of cadmium chloride. GPC was prepared ...
Hocquellet Agnès - - 2005
We investigated phosphatidylcholine (PC) and phosphatidylethanolamine (PE) labelling in shoots and roots from leek plantlets, maize seedlings and Arabidopsis thaliana through the incorporation of radiolabelled acetate. Regardless of the pathway followed in shoots, PC labelling was always higher than PE labelling. However, we obtained an opposite situation in leek and ...
Harder A - - 2005
The research of the class of cyclic octadepsipeptides started at the beginning of the 1990s. PF1022A, the starting material of emodepside, is a natural secondary metabolite of the fungus Mycelia sterilia, which belongs to the microflora of the leaves of Camellia japonica. PF1022A consists of four N-methyl-L-leucins, two D-Iactic acids ...
Nakamura Noriko - - 2005
Phospholipase D (PLD) is known to play a role in vesicle transport through the hydrolysis of phosphatidylcholine (PC) to produce the bioactive lipid, phosphatidic acid. Lipid droplets (LDs) are surrounded by a monolayer of phospholipids, including PC and its lyso derivative, and exhibit a number of signaling proteins. Our recent ...
Ryu Stephen B - - 2005
Phospholipase A2s (PLA2s) are enzymes that liberate lysophospholipids and free fatty acids (FFAs) from membrane phospholipids in response to hormones and other external stimuli. This report describes the cloning and functional characterization of a PLA2 cDNA from Arabidopsis thaliana, AtsPLA2-alpha, which represents one of four secretory PLA2 (sPLA2) genes in ...
Lecompte Marie-France - - 2005
4-Hydroxynonenal (4HNE), generated during polyunsaturated fatty acid oxidation, is present in atherosclerotic lesions. As 4HNE is able to react with phosphatidylethanolamine (PE), we investigated, using AC polarography, whether it may alter the physico-chemical state of a condensed PE-containing phospholipid monolayer and its interaction with apoA-I. The stability of a phospholipid ...
Kafoury Ramzi M - - 2005
The sequence of events leading to ozone-induced airway inflammation is not well known. To elucidate the molecular and cellular events underlying ozone toxicity in the lung, we hypothesized that lipid ozonation products (LOPs) generated by the reaction of ozone with unsaturated fatty acids in the epithelial lining fluid and cell ...
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