Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.4.3 (phospholipase C)
 18,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Total membranes from Escherichia coli cells grown in different fatty acid-supplemented media have been examined by 31P NMR at different pH values. The isolated inner and outer membranes were also studied and compared to the liposomes formed with the corresponding extracted lipids. While the liposomes show structures that are correlated with lipid composition, degree of fatty acid unsaturation, and pH, the membrane structure is mainly bilayer. The presence of two bilayer phases characterized by different chemical shift anisotropy values (delta nu csa) is detectable at neutral pH; a perturbation of the bilayer phase characterized by the smallest delta nu csa is produced by low pH. Moreover, an isotropic peak is always present in the membrane NMR spectra: its attribution to cardiolipin molecules is discussed on the basis of digestion experiments with phospholipase C.
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PMID:Effects of decreased pH on membrane structural organization of Escherichia coli grown in different fatty acid-supplemented media: a 31P NMR study. 218 34

The phosphosaccharide-inositol core of the lipophosphoglycan of Leishmania donovani was generated by treatment of the glycoconjugate with mild acid and digestion with phosphatidylinositol-specific phospholipase C. The core was purified and examined by one- and two-dimensional 1H-1H NMR and by methylation analysis. From the results, the carbohydrate core was elucidated as a phosphosaccharide attached to the inositol residue of the lyso-alkylphosphatidylinositol anchor of lipophosphoglycan as follows: PO4----6GalP(alpha 1----6)GalP(alpha 1----3)Galf(alpha 1----3)ManP(alpha 1----3)ManP(alpha 1----4)GlcNP(alpha 1----6)myo-inositol. The presence of an internal galactofuranose residue is highly unusual and the ManP(alpha 1----4)GlcNP(alpha 1----6)myo-inositol sequence is homologous to the respective portion of the glycosylphosphatidylinositol anchors reported for both the Trypanosoma brucei variant surface glycoprotein and the rat brain Thy-1 glycoprotein.
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PMID:Structure of the phosphosaccharide-inositol core of the Leishmania donovani lipophosphoglycan. 270 38

A new method has been developed to analyze the primary products of phospholipid peroxidation. The procedure utilizes the ability of phospholipase C to hydrolyze phospholipid hydroperoxides to their corresponding diacylglycerol derivatives. 1-Palmitoyl-2-linoleoylphosphatidylcholine (1P,2L-GPC), 1-stearoyl-2-linoleoylphosphatidylcholine (1S,2L-GPC), and 1-stearoyl-2-arachidonylphosphatidylcholine (1S,2A-GPC) were autoxidized. The diacylglycerol hydroxides derived from the phosphatidylcholine hydroperoxides were separated by reverse-phase high-pressure liquid chromatography (RP-HPLC) and normal-phase high-pressure liquid chromatography (NP-HPLC). 1P,2L-diglyceride (1P,2L-DG) and 1P,2A-DG products were easily separated from 1S,2L-DG and 1S,2A-DG products by RP-HPLC. The linoleate diglyceride oxidation mixture was separated into the 13-trans/cis, 13-trans/trans, 9-trans/cis, and 9-trans/trans isomers by NP-HPLC. Likewise, 1P,2A-DG and 1S,2A-DG oxidation products were resolved into the 15-trans/cis, 15-trans/trans, 12-trans/cis, 11-trans/cis, 9-trans/cis, 8-trans/cis, and 5-trans/cis isomers. In both of the above cases, the 1,2-diacylglycerol isomers could be separated from the 1,3 isomers. Moreover, the diastereomers of the 9-, 8-, and 5-hydroxides could be separated. Each of the diacylglycerol oxidation products was characterized by (1) proton nuclear magnetic resonance (proton NMR), (2) electron ionization-mass spectrometry (EI-MS), and (3) NP-HPLC of the corresponding fatty acids. The diacylglycerol analysis provided the same results for the autoxidation of 1P,2L-GPC as the fatty acid methyl ester analysis. In addition, when 1S,2A-GPC was autoxidized in the presence of 5% alpha-tocopherol, both diastereomers of the 5-hydroxide were observed in the same proportions as the other hydroxides.
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PMID:A phospholipase C protocol for phospholipid peroxidation analysis. 297 43

The transverse distribution of the phospholipids in vesicular H+-translocating membranes prepared from pig gastric mucosa was investigated with the aid of phospholipase C, sphingomyelinase, and trinitrobenzenesulfonic acid. The major part (80-90%) of the phosphatidylcholine and the phosphatidylethanolamine, 60% of the phosphatidylserine, and 45% of the sphingomyelin was located on the external, cytoplasmic side of the vesicle membranes. After treatment with phospholipase C the vesicles still behaved as osmometers and appeared as closed vesicles on the electron micrographs. 31P NMR indicated that the phospholipids in untreated vesicles as well as the unhydrolyzed phospholipids in phospholipase C-treated vesicles were arranged in lamellar structures. The 31P NMR spectrum of untreated vesicles to which Pr3+ ions had been added supported the conclusion that the major part of the membrane phospholipids was located on the external surface of the vesicles. A small fraction of the lipids, 3.6 mol %, was found to consist of glycosphingolipids which occurred at a concentration of 52 nmol/mg of protein.
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PMID:Phospholipid organization in H,K-ATPase-containing membranes from pig gastric mucosa. 299 6

Soybean lipoxygenase was reacted with phosphatidylcholine (at pH 9, with 10 mM deoxycholate), and the oxygenation products were analyzed by high-pressure liquid chromatography, UV, gas chromatography-mass spectrometry (GC-MS), and NMR. The structures of the intact glycerolipid products were established by GC-MS of diglycerides recovered by phospholipase C hydrolysis and by proton NMR of the intact phosphatidylcholine. These analyses, together with analyses of the transesterified fatty acids, indicated that arachidonyl and linoleoyl moieties in the phosphatidylcholine were converted exclusively to the 15(S)-hydroperoxy-5(Z),8(Z),11(Z),13(E)-eicosatetraenoate and 13(S)-hydroperoxy-9(Z),11(E)-octadecadienoate analogues, respectively. Control experiments proved that the intact phospholipid (and not hydrolyzed/reesterified fatty acid) was the true substrate of the oxygenation reaction. Phosphatidylethanolamine and phosphatidylinositol lipids were also substrates for specific oxygenation by the soybean lipoxygenase. The results provide concrete evidence that fatty acids esterified in phospholipid can be subject to highly specific oxygenation by a lipoxygenase enzyme.
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PMID:Analysis of a specific oxygenation reaction of soybean lipoxygenase-1 with fatty acids esterified in phospholipids. 311 47

We describe the isolation and characterization of a novel four-chain ether phospholipid in Clostridium butyricum grown on petroselinic acid in the absence of biotin. The results of quantitative analyses of hydrolytic products, selective hydrolysis by mild acid or phospholipase C, 1H-, 13C-, and 31P-NMR, and fast atom bombardment-mass spectroscopy (FABMS) have resulted in the determination of the structure of this lipid as a phosphatidylglycerol acetal of plasmenylethanolamine. Smaller amounts of this lipid have been found in cells grown under similar conditions in the presence of oleic, cis-vaccenic, elaidic or dihydrosterculic acids. It also appears to be present in small amounts in cells grown with biotin. This lipid is structurally related to the more plentiful glycerol acetal of plasmenylethanolamine found in these cells.
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PMID:Isolation and characterization of a novel four-chain ether lipid from Clostridium butyricum: the phosphatidylglycerol acetal of plasmenylethanolamine. 338 87

Phospholipase C (phosphatidylcholine cholinephosphohydrolase, EC 3.1.4.3) (Bacillus cereus) activity toward diheptanoylphosphatidylcholine is increased 50-100% by low concentrations of both positively and negatively charged detergents. Zwitterionic and nonionic detergents have no such activating effect. This charged detergent activation requires an interface, since comparable detergent concentrations have no effect on the hydrolysis rate of monomeric dihexanoylphosphatidylcholine. From NMR and diacylglycerol solubility studies it is suggested that activation results from detergent interacting with diacylglycerol to accelerate product release from the enzyme.
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PMID:Charged detergents enhance the activity of phospholipase C (Bacillus cereus) towards micellar short-chain phosphatidylcholine. 392 39

Several seven-carbon fatty acyl lecithins with varied acyl chain branching have been synthesized and characterized as potential phospholipase A2 substrates. Micellar bis(4,4-dimethylpentanoyl) phosphatidylcholine, bis(5-methylhexanoyl)phosphatidylcholine, bis(3-methylhexanoyl)phosphatidylcholine, and bis(2-methylhexanoyl)phosphatidylcholine are poor substrates for phospholipase A2 (Naja naja naja). These branched lecithins also inhibit the hydrolysis of diheptanoylphosphatidylcholine by the enzyme with Ki values comparable to or smaller than the apparent Km of the linear compound. The terminally branched lecithins are excellent substrates for another surface-active hydrolytic enzyme, phospholipase C from Bacillus cereus. When only one acyl chain bears a methyl group, the hybrid lecithins 1-heptanoyl-2-(2-methylhexanoyl)phosphatidylcholine and 1-(3-methylhexanoyl)-2-heptanoylphosphatidylcholine are substrates comparable to diheptanoylphosphatidylcholine. Analysis of micellar structure and dynamics by 1H and 13C NMR spectroscopy, quasi-elastic light scattering, and comparison of critical micellar concentrations indicates little significant difference in the conformation and dynamics of these seven-carbon fatty acyl lecithin micelles, even when the methyl groups are adjacent to the carbonyls. Phospholipase A2 UV difference spectra induced by phospholipid binding imply different enzyme conformations or aggregation states caused by linear-chain and asymmetric-chain lipids compared to bis(methylhexanoyl)phosphatidylcholines. The differences in hydrolytic activity of phospholipase A2 against the branched-chain micellar lecithins can then be attributed to an enzyme-lipid interaction at the active site. The species with both fatty acyl chains branched bind to phospholipase A2 but are not turned over rapidly. Since poor enzymatic activity only occurs for lecithins with both chains methylated, the interaction of both chains with the enzyme must be important for catalytic efficiency.
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PMID:Methyl branching in short-chain lecithins: are both chains important for effective phospholipase A2 activity? 398 78

1. Fresh human erythrocytes were treated with lytic and non-lytic combinations of phospholipases A2, C and sphingomyelinase. The 31P-NMR spectra of ghosts derived from such erythrocytes show that, in all cases, the residual phospholipids and lysophospholipids remain organized in a bilayer configuration. 2. A bilayer configuration of the (lyso)phospholipids was also observed after treatment of erythrocyte ghosts with various phospholipases even in the case that 98% of the phospholipid was converted into lysophospholipid (72%) and ceramides (26%). 3. A slightly decreased order of the phosphate group of phospholipid molecules, seen as reduced effective chemical shift anisotropy in the 31P-NMR spectra, was found following the formation of diacyglycerols and ceramides in the membrane of intact erythrocytes. Treatment of ghosts always resulted in an extensive decrease in the order of the phosphate groups. 4. The results allow the following conclusions to made: a. Hydrolysis of phospholipids in intact red cells and ghosts does not result in the formation of non-bilayer configuration of residual phospholipids and lysophospholipids. b. Haemolysis, which is obtained by subsequent treatment of intact cells with sphingomyelinase and phospholipase A2, or with phospholipase C, cannot be ascribed to the formation of non-bilayer configuration of phosphate-containing lipids. c. Preservation of bilayer structure, even after hydrolysis of all phospholipid, shows that other membrane constitutents, e.g. cholesterol and/or membrane proteins play an important role in stabilizing the structure of the erythrocyte membrane. d. A major prerequisite for the application of phospholipases in lipid localization studies, the preservation of a bilayer configuration during phospholipid hydrolysis, is met for the erythrocyte membrane.
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PMID:Preservation of bilayer structure in human erythrocytes and erythrocyte ghosts after phospholipase treatment. A 31P-NMR study. 735 1

Hispidospermidin (1) is a novel phospholipase C inhibitor produced by Chaetosphaeronema hispidulum (Cda) Moesz NR 7127. Its structure (C25H47N3O) has been elucidated as a cage compound with a trimethylspermidine side chain based on various NMR studies, including 1H-1H COSY, 13C-1H COSY, HOHAHA, HMBC, COLOC and long range J C-H resolved 2D spectroscopy. The absolute configuration of 1 has been elucidated by modified Mosher's method on the (R)- and (S)-MTPA amides of a derivative of 1.
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PMID:Hispidospermidin, a novel phospholipase C inhibitor produced by Chaetosphaeronema hispidulum (Cda) Moesz NR 7127. II. Isolation, characterization and structural elucidation. 750 87


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