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Vikbjerg Anders F - - 2005
Thin-layer chromatography with a flame ionization detector (TLC-FID) was used for monitoring the production of structured phospholipids (ML type: L, long-chain fatty acids; M, medium-chain fatty acids) by enzyme-catalyzed acidolysis between soybean phosphatidylcholine (PC) and caprylic acid. It was found that the structured PC fractionated into two to three distinct ...
Gauster M - - 2005
We assessed the ability of endothelial lipase (EL) to hydrolyze the sn-1 and sn-2 fatty acids (FAs) from HDL phosphatidylcholine. For this purpose, reconstituted discoidal HDLs (rHDLs) that contained free cholesterol, apolipoprotein A-I, and either 1-palmitoyl-2-oleoylphosphatidylcholine, 1-palmitoyl-2-linoleoylphosphatidylcholine, or 1-palmitoyl-2-arachidonylphosphatidylcholine were incubated with EL- and control (LacZ)-conditioned media. Gas chromatography analysis ...
Kooijman Edgar E - - 2005
The formation of phosphatidic acid (PA) from lysophosphatidic acid (LPA), diacylglycerol, or phosphatidylcholine plays a key role in the regulation of intracellular membrane fission events, but the underlying molecular mechanism has not been resolved. A likely possibility is that PA affects local membrane curvature facilitating membrane bending and fission. To ...
Murray J Pedro Fernández - - 2005
Deciphering the function of the essential yeast Sec14p protein has revealed a regulatory interface between cargo secretion from Golgi and lipid homeostasis. Abrogation of the CDP-choline (CDP-Cho) pathway for phosphatidylcholine (PC) synthesis allows for life in the absence of the otherwise essential Sec14p. Nte1p, the product of open reading frame ...
Ng Michael N P - - 2004
During entry into the cell cycle a phosphatidylcholine (PC) metabolic cycle is activated. We have examined the hypothesis that PC synthesis during the G(0) to G(1) transition is controlled by one or more lipid products of PC turnover acting directly on the rate-limiting enzyme in the synthesis pathway, CTP: phosphocholine ...
Vickery S - - 2004
The study was established to assess the potential for a variety of xenobiotic aromatic carboxylic acids to be incorporated into glycerolipids. The 14C-labelled xenobiotic acids were included in incubations of cultured 3T3-L1 adipocytes under defined conditions. Lipids were extracted and identified by TLC and radioscanning. Ibuprofen, 4-(2,4-dichlorophenoxy)-butanoic acid (2,4-DB), 4-(2-methyl-4-chlorophenoxy)-butanoic ...
Sato Rina - - 2004
A simple method for synthesizing diastereomerically pure phosphatidylglycerols (PtdGro), namely, 1,2-diacyl-sn-glycero-3-phospho-3'-sn-glycerol (R,R configuration) and 1,2-diacyl-sn-glycero-3-phospho-1'-sn-glycerol (R,S configuration), was established. For this purpose, diastereomeric 1,2-O-isopropylidene PtdGro were prepared from 1,2-diacyl-sn-glycero-3-phosphocholine (PtdCho) and enantiomeric 1,2-O-isopropylideneglycerols by transphosphatidylation with phospholipase D (PLD) from Actinomadura sp. This species was selected because of its higher ...
Zhang Weihua - - 2004
Pteris vittata (Chinese brake fern) has potential for phytoremediation of As-contaminated sites. In this study, the synthesis of total thiols and acid-soluble thiols in P. vittata was investigated under arsenic exposure. The strong and positive correlation between As concentration and acid-soluble thiols in plant leaflets suggests that acid-soluble thiols may ...
Aikens Christopher L - - 2004
The automated docking program AutoDock was used to dock nine phosphatidic acids (PAs), six phosphatidylcholines, five phosphatidylethanolamines, four phosphatidylglycerols, one phosphatidylinositol and two phosphatidylserines, which have two identical saturated fatty acid residues with an even numbers of carbon atoms, onto the active site of Streptomyces sp. PMF phospholipase D (PLD). ...
Hirano Kaoru - - 2004
1,2-Didocosahexaenoyl phosphatidylcholine (PC), which has highly unsaturated fatty acid at both sn-1 and sn-2 positions of glycerol, is a characteristic molecular species of bonito muscle. To examine the involvement of a de novo route in its synthesis, the molecular species of phosphatidic acid (PA) were analyzed by matrix-assisted laser desorption/ionization ...
Farooqui Akhlaq A - - 2004
The phospholipases A2 (PLA2) belong to a large family of enzymes involved in the generation of several second messengers that play an important role in signal transduction processes associated with normal brain function. The phospholipase A2 family includes secretory phospholipase A2, cytosolic phospholipase A2, calcium-independent phospholipase A2, plasmalogen-selective phospholipase A2 ...
Noiriel Alexandre - - 2004
During a search for cDNAs encoding plant sterol acyltransferases, we isolated four full-length cDNAs from Arabidopsis thaliana that encode proteins with substantial identity with animal lecithin : cholesterol acyltransferases (LCATs). The expression of one of these cDNAs, AtLCAT3 (At3g03310), in various yeast strains resulted in the doubling of the triacylglycerol ...
Canavoso Lilián E - - 2004
The metabolism of dietary lipids in the anterior midgut of Panstrongylus megistus during blood digestion was studied. Fifth instar nymphs were fed a blood meal containing 7.1 +/- 0.4 mg of lipids, consisting mainly of triacylglycerol (TAG), and completed the overall process of digestion in about 20 days. Lipolysis of ...
Onyango Arnold N - - 2004
Phosphatidylcholines (PCs) having an acyl chain with a 2,4-dienal terminal are expected to be important bioactive compounds formed during lipid peroxidation in vivo. However, they have not been isolated from biological tissues. Here we used electrospray mass spectroscopy to investigate whether a high autoxidative instability may contribute to the difficulty ...
Tserng Kou-Yi - - 2004
The traditional (parallel) model of molecular species synthesis of phosphatidylcholine is based on the substrate specificity of two glycerolphosphate acyltransferases. Preformed molecular species of diacylglycerols are then converted to phosphatidylcholine. In this investigation, we used [1,2,3,4-(13)C(4)]palmitate as a tracer to determine the turnover rates of diacylglycerols and phosphatidylcholines. In HL60 ...
Shadyro Oleg - - 2004
By use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, phosphatidic acid was found to be the main product of gamma radiolysis of cardiolipin, phosphatidylinositol, and phosphatidylglycerol. It has been shown that gamma irradiation of such glycolipids as cerebroside and galactosyl diglyceride leads to formation of ceramide and diglyceride, respectively. These ...
Loewen C J R - - 2004
Cells regulate the biophysical properties of their membranes by coordinated synthesis of different classes of lipids. Here, we identified a highly dynamic feedback mechanism by which the budding yeast Saccharomyces cerevisiae can regulate phospholipid biosynthesis. Phosphatidic acid on the endoplasmic reticulum directly bound to the soluble transcriptional repressor Opi1p to ...
Yu Bin - - 2004
Phosphatidic acid is a key intermediate for chloroplast membrane lipid biosynthesis. De novo phosphatidic acid biosynthesis in plants occurs in two steps: first the acylation of the sn-1 position of glycerol-3-phosphate giving rise to lysophosphatidic acid; second, the acylation of the sn-2 position of lysophosphatidic acid to form phosphatidic acid. ...
Wang Pingzhen - - 2004
As part of a collaborative study of cellular efflux of cholesterol and phospholipids, photoactivable analogues 4-8 of phosphatidylcholine (PC) having benzophenone groups in the choline moiety and at the end of the C2 and C1 alkyl chains have been synthesized. The efficient preparation via Suzuki coupling of the appropriate long-chain ...
Lin Jiann-Tsyh - - 2004
The incorporations of oleate (endogenous) and ricinoleate (nonendogenous) into phosphatidylcholine (PC) and acylglycerol (AG) in immature soybean microsomes were compared. [(14)C]Oleate and [(14)C]ricinoleate were incubated individually with soybean microsomal preparations for up to 4 h, and molecular species of PC and AG incorporated were identified and quantified by HPLC. The ...
Sugiyama Michiyo - - 2004
OBJECTIVE: Lysophosphatidic acid stimulates the proliferation of ovarian cancer cell through specific members of the guanosine triphosphate-binding protein-coupled receptor family. We attempted to identify the guanosine triphosphate-binding protein subtypes that are linked to lysophosphatidic acid receptor-stimulated production of cytokine, which are involved potentially in ovarian cancer development. STUDY DESIGN: Cytokine ...
Aoki Kazuhiro - - 2004
Novel ZGLs (zwitterionic glycosphingolipids) have been found in and extracted from the mycelia of filamentous fungi ( Acremonium sp.) isolated from soil. Five ZGLs (ZGL1-ZGL5) were structurally elucidated by sugar compositional analysis, methylation analysis, periodate oxidation, matrix-assisted laser-desorption ionization-time-of-flight MS, (1)H-NMR spectroscopy and fast-atom bombardment MS. Their chemical structures were ...
Lin Jianming - - 2004
The role of molecular organization in heated aqueous dispersions of egg phosphatidylcholine (PC) and egg phosphatidylethanolamine (PE) was studied with respect to the formation of key odorants. Evidence was found for the crucial role of self-assembly structures adopted by phospholipid molecules on the quantitative composition of volatile constituents. The concentrations ...
Rasi Silvia - - 2004
It is accepted by many authors that the formation of closed molecular structures is a key step in the evolution of life. Oleate vesicles represent a good model system in this framework due to the fact that they self-assemble spontaneously and that fatty acids are considered as possible prebiotic structures. ...
Phillis John W - - 2004
Phospholipases are a diverse group of enzymes whose activation may be responsible for the development of injury following insult to the brain. Amongst the numerous isoforms of phospholipase proteins expressed in mammals are 19 different phospholipase A2's (PLA2s), classified functionally as either secretory, calcium dependent, or calcium independent, 11 isozymes ...
Leslie Christina C - - 2004
Mammalian cells contain many structurally and functionally diverse phospholipases A2 (PLA2) that catalyze the hydrolysis of sn-2 fatty acid from membrane phospholipid. Assays are described for measuring the activity of Group IVA cytosolic PLA2alpha(cPLAalpha) and for secreted PLA2s (sPLA2) that are suitable for purified enzymes and for measuring activity in ...
Kubo Kazuhiro - - 2004
We examined the relationship between the transbilayer distribution of aminophospholipids, such as phosphatidylethanolamine (PE), PE plasmalogen and phosphatidylserine, and the oxidative stability of polyunsaturated fatty acids (PUFAs) in the aminophospholipids. To modulate the transbilayer distribution of aminophospholipid in liposomes, we used phosphatidylcholine (PC) with two types of acyl chain region: ...
Arai Kazuya - - 2004
In order to discover novel invertebrate cytokines from the budding tunicate, Polyandrocarpa misakiensis, we treated the water-insoluble fraction of tunicate homogenates with trypsin. The extracts showed remarkable activities to promote the growth and motility of tunicate cells. The activities were heat-stable and proteinase K-resistant. After anion exchange chromatography, the activities ...
Zhao Yue - - 2003
We previously described a point mutation in human LCAT (E to A at residue 149; hE149A) that demonstrated greater activity with phosphatidylcholine (PC) substrate containing 20:4 in the sn-2 position compared with the wild-type enzyme [hLCAT; Wang et al. (1997) J. Biol. Chem. 272, 280-286], resulting in a human enzyme ...
Sun Grace Y - - 2004
Phospholipase A2 (PLA2) belongs to a family of enzymes that catalyze the cleavage of fatty acids from the sn-2 position of phospholipids. There are more than 19 different isoforms of PLA2 in the mammalian system, but recent studies have focused on three major groups, namely, the group IV cytosolic PLA2, ...
Schiller Jürgen - - 2003
In this study we demonstrated the combination of MALDI-TOF MS and TLC as a fast and powerful tool to investigate the phospholipid (PL) composition of organic extracts of bull spermatozoa. Since phosphatidylcholine (PC) is the dominant PL species, an adequate resolution of MALDI-TOF spectra for sphingomyelin (SM) or phosphatidylethanolamine (PE) ...
Murakami Makoto - - 2003
PURPOSE OF REVIEW: Inflammation is an integral feature of atherosclerosis, in which inflammatory processes contribute to the initiation, progression and rupture of lipid-rich atherosclerotic plaques. Recent studies have suggested the involvement of the proinflammatory secretory phospholipase A2 (sPLA2)-IIA in the development of atherosclerosis. This enzyme has been proposed to hydrolyze ...
Brockman Howard L - - 2003
Mammalian synaptic membranes appear to contain high proportions of specific, sn-1-stearoyl-2-docosahexaenoyl- and sn-1-stearoyl-2-arachidonoyl phosphoglycerides, but the structural significance of this is unclear. Here we used a standardized approach to compare the properties of homogeneous monolayers of the corresponding phosphatidylcholines, phosphatidylethanolamines, phosphatidylserines, and phosphatidic acids with those of control monolayers of ...
Hakkarainen Minna - - 2003
A solid-phase microextraction (SPME) method was developed to quantitatively determine the amount of 6-hydroxyhexanoic acid in aqueous solutions. The SPME method in combination with GC-MS was then applied to identify and quantify the low-molecular-mass compounds migrating from a new poly(vinyl chloride) (PVC) material, PVC/polycaprolactone-polycarbonate (PCL-PC) during ageing in water. It ...
Ekroos Kim - - 2003
The molecular composition of phosphatidylcholines (PCs) in total lipid extracts was characterized by a combination of multiple precursor ion scanning on a hybrid quadrupole time-of-flight mass spectrometer and MS3 fragmentation on an ion trap mass spectrometer. Precursor ion spectra for 50 acyl anion fragments of fatty acids (fatty acid scanning) ...
Salto Maria Laura - - 2003
Differentiation of Trypanosoma cruzi trypomastigotes to amastigotes inside myoblasts or in vitro, at low extracellular pH, in the presence of [(3)H]palmitic acid or [(3)H]inositol revealed differential labeling of inositolphosphoceramide and phosphatidylinositol, suggesting that a remodeling process takes place in both lipids. Using (3)H-labeled inositolphosphoceramide and phosphatidylinositol as substrates, we demonstrated ...
Mulder C - - 2003
Choline containing phospholipids are essential for the integrity of the'cell'membrane. Minor changes in the lysophosphatidylcholine (lyso-PC)/phosphatidylcholine (PC) ratio may lead to neuronal damage and cell loss. Several studies have shown protein and lipid oxidation in Alzheimer's disease (AD) affected brain regions. Amyloid-beta peptides may induce free-radical oxidative stress which normally ...
Adibhatla Rao Muralikrishna - - 2003
Neuroprotection by citicoline (CDP-choline) in transient cerebral ischemia has been demonstrated previously. Citicoline has undergone several Phase III clinical trials for stroke, and is being evaluated for treatment of Alzheimer's and Parkinson's diseases. Phospholipid degradation and generation of reactive oxygen species (ROS) are major factors causing neuronal injury in CNS ...
Lin Jianming - - 2003
The qualitative and quantitative aroma composition of heated aqueous dispersions of egg phosphatidylcholine (PC) and egg phosphatidylethanolamine (PE) were characterized by aroma extract dilution analysis and isotope dilution assay. On the basis of FD-factors and odor activity values, trans-4,5-epoxy-(E)-2-decenal was found to be the most potent odorant followed by (E,E)-2,4-decadienal, ...
Sato Norihiro - - 2003
The fatty acid distributions at the sn-1 and sn-2 positions in major chloroplast lipids of Chlorella kessleri 11h, monogalactosyl diacylglycerol (MGDG) and digalactosyl diacylglycerol (DGDG), were determined to show the coexistence of both C16 and C18 acids at the sn-2 position, i.e. of prokaryotic and eukaryotic types in these galactolipids. ...
Krasilnikova O A - - 2003
The role of calcium ions in the L-thyroxine-induced initiation of hydrolysis of phosphatidylinositol 4,5-bisphosphate (PtdInsP2) and also the course of releasing individual fractions of inositol phosphates and diacylglycerides (DAG) were studied in liver cells during early stages of the hormone effect. L-Thyroxine stimulated a rapid hydrolysis in hepatocytes of PtdInsP2 ...
Wenk Markus R MR Howard Hughes Medical Institute, Department of Cell Biology, Yale University School of Medicine, Boyer Center for Molecular Medicine, 295 Congress Avenue, New Haven, Connecticut 06511, USA. - - 2003
Phosphoinositides (phosphorylated derivatives of phosphatidylinositol, PI) are versatile intracellular signaling lipids whose occurrence in low concentrations complicates direct mass measurements. Here we present a sensitive method to detect, identify and quantify phosphatidylinositol phosphate (PIP) and phosphatidylinositol bisphosphate (PIP(2)) with different fatty acid compositions (phosphoinositide profiles) in total lipid extracts by ...
Jouhet Juliette - - 2003
In plants, phosphate deprivation is normally known to decrease the phospholipid content consistent with a mobilization of the phosphate reserve, and conversely to increase non-phosphorous membrane lipids such as digalactosyldiacylglycerol. We report here that unexpectedly, at an early stage of phosphate starvation, phosphatidylcholine (PC) increases transiently. We also show that ...
Arisz Steven A - - 2003
In response to various environmental stress conditions, plants rapidly form the intracellular lipid second messenger phosphatidic acid (PA). It can be generated by two independent signalling pathways via phospholipase D (PLD) and via phospholipase C (PLC) in combination with diacylglycerol kinase (DGK). In the green alga Chlamydomonas, the phospholipid substrates ...
Ichihara Ken'ichi - - 2003
In developing seeds of Perilla frutescens var. crispa, the triacylglycerol fraction was found to accumulate between 15 and 19 days after flowering. Of this, 65% of the total fatty acids was alpha-linolenic acid in the mature seeds, with the latter being esterified in comparable amounts at all positions (sn-1, 2 ...
Hsu Fong-Fu - - 2003
We applied low-energy collisionally activated dissociation (CAD) tandem quadrupole mass spectrometry to study the fragmentation pathways of the [M + H](+) and [M + Li](+) ions of phosphatidylcholine (PC), generated by electrospray ionization (ESI). It is revealed that the fragmentation pathways leading to loss of the polar head group and ...
Al-Saad Khalid A - - 2003
The utility of post-source decay (PSD) matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was investigated for the structural analysis of phosphatidylcholine (PC). PC did not produce detectable negative molecular ion from MALDI, but positive ions were observed as both [PC+H](+) and [PC+Na](+). The PSD spectra of the protonated PC species ...
Fang Xiang - - 2003
Epoxyeicosatrienoic acids (EETs) are readily incorporated into phospholipids of smooth muscle cells (SMC) and endothelial cells (EC). Incorporation of EETs into intact porcine coronary arteries potentiates EC-dependent relaxation, but not vasorelaxation induced by agents that act solely on SMC. To explore the potential mechanisms responsible for this difference, porcine coronary ...
Kooijman Edgar E - - 2003
The local generation of phosphatidic acid plays a key role in the regulation of intracellular membrane transport through mechanisms which are largely unknown. Phosphatidic acid may recruit and activate downstream effectors, or change the biophysical properties of the membrane and directly induce membrane bending and/or destabilization. To evaluate these possibilities, ...
Kubiak Robert J - - 2003
Studies of cellular signal transduction mechanisms involving receptor-mediated generation of inositol phosphates and phosphorylated phosphatidylinositols require easy access to these naturally occurring products. Although numerous synthetic methods have been developed during the past decade, most of these methods suffer from excessive length and lack of generality. In this work we ...
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