Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.5 (neuropathy target esterase)
 1,070 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It has been well recognized that acyl groups of phospholipids play an important role for structure and function of biomembrane. The turnover of these acyl groups in normal brain biomembrane is also well known. Some types of enzymic system related to this turnover has been investigated. Phospholipase A, PI-specific phospholipase C, lipase, lysophospholipase and acylCoA: lysophospholipid acyltransferase belong to these enzymic systems. In this report, the sequential changes of phospholipase A, PI-specific phospholipase C, lipase, lysophospholipase and acylCoA: lysophospholipid acyltransferase activities in ischemic rat brain were examined. The purpose of this study was to examine the enzymic changes of deacylation-reacylation cycle of biomembrane phospholipid in ischemic brain. Ischemic brain were produced by decapitation and activities of 5 enzymes were assayed in microsomal fraction. The activities of phospholipase A, PI-specific phospholipase C, lipase showed high value during early stage of ischemia for 15 or 30 min and then decreased gradually. Lysophospholipase activity was not changed for 120 min. On the other hand, acylCoA: lysophospholipid acyltransferase activity showed gradual decrease from the beginning of ischemia. There are some reports that in early ischemic stage, the concent of free fatty acids increase, while that of phospholipid decrease. The present results may suggest that the changes of free fatty acid and phospholipid in ischemic brain are related to these enzymic system.
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PMID:[The activities of phospholipase A, PI-specific phospholipase C, lipase, lysophospholipase and acylCoA: lysophospholipid acyltransferase in ischemic brain microsomal fraction]. 402 86

Phospholipase and lysophospholipase activities were assayed in goat epididymal spermatozoa. Lysophospholipase was 10 times more active than phospholipase, and both enzymes decreased in activity substantially in the transit of spermatozoa from the caput to the cauda epididymidis. A comparative study revealed that phosphatidyl-ethanolamine, -choline and -inositol and phosphatidic acid were hydrolysed by goat sperm phospholipase. Hydrolysis of phosphatidylethanolamine/phosphatidylcholine revealed the end products to be glycerophosphoethanolamine/choline but neither diglycerides nor lysophosphatidylethanolamine/lysophosphatidylcholine were detected.
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PMID:Phospholipase and lysophospholipase activities of goat spermatozoa in transit from the caput to the cauda epididymidis. 404 28

Phospholipase B bound tightly to the membrane fraction of baker's yeast (Saccharomyces cerevisiae) was purified approximately 226-fold by extraction with sodium deoxycholate (DOC), acetone precipitation, ammonium sulfate fractionation, and column chromatographies on Phenyl-Sepharose CL-4B, DEAE-Sepharose CL-6B, and Sepharose 4B. Only one major activity peak with an apparent molecular weight of 330,000 was detected by gel filtration on Sepharose 4B. However, two glycoprotein bands, one major and one minor, were evident on SDS-polyacrylamide gel electrophoresis in the absence of 2-mercaptoethanol. Isoelectric focusing also revealed two activities, pI 3.4 (major) and pI 3.0 (minor). The purified enzyme had phospholipase B activity (in the presence of DOC) and lysophospholipase activity in a ratio of 1:4.8. Both activities had an optimum pH of 3.5-4.0. Phospholipase B activity was appreciably stimulated only by DOC among bile acids, but lysophospholipase activity was markedly inhibited by them. Both activities were not stimulated by Ca2+ and inhibited by SDS, Triton X-100, Fe3+ and Al3+. The purified enzyme hydrolyzed the acyl ester bonds of phosphatidylcholine sequentially, first the 2-acyl and then the 1-acyl groups. It preferentially hydrolyzed 1-acyl-sn-glycero-3-phosphocholine and, to a lesser degree, 2-acyl-sn-glycero-3-phosphocholine.
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PMID:Purification and properties of a membrane-bound phospholipase B from baker's yeast (Saccharomyces cerevisiae). 636 32

Phospholipase B and lysophospholipase activity is secreted from yeast cells (Saccharomyces cerevisiae) growing aerobically in batch cultures during the exponential phase. A glycoprotein with both activities running on SDS-polyacrylamide slab gels as a broad band between 200 000 and 280 000 Da was purified about 2500-fold by gel filtration, chromatofocusing and hydrophobic interaction chromatography with octyl-Sepharose. The secreted phospholipase has a slightly higher carbohydrate content of 41 mumol/mg protein compared to a form of the enzyme associated to the plasma membrane described in the previous communication (Witt, W., Schweingruber, M.E. and Mertsching, A. (1984) Biochim. Biophys. Acta 795, 108-116) and exerts very similar enzymatic properties. Fatty acids are set free from lysophosphatidylcholine with a 68-fold higher rate than from phosphatidylcholine with a concomitant generation of the corresponding diacyl compound. pH optima of 3.0 and 3.5 were determined with phosphatidylcholine and lysophosphatidylcholine, respectively. During the enzymatic degradation of the cell wall, high amounts of phospholipase activity were released, indicating that the enzyme is present in the periplasmatic space or associated to cell wall components.
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PMID:Secretion of phospholipase B from Saccharomyces cerevisiae. 638 May 92

The hydrolysis of phosphatidylethanolamine, phosphatidylcholine, lysophosphatidylcholine, and trioleoylglycerol by Leptospira biflexa strain Urawa was studied in vitro. Phospholipase A1 was identified by the formation of 32P- and 14C-labeled lysoderivatives from 32P-phosphatidylcholine, 32P-phosphatidylethanolamine, or 1-acyl-2-[1-14C]oleoyl-sn-glycero-3-phosphorylcholine. Phospholipase A1 activity was independent of lipase in the microorganism since 14C-labeled trioleoylglycerol was scarcely attacked under the same conditions in which the phospholipids were hydrolyzed. Lysophospholipase activity was also demonstrated using 32P- and non-labeled lysophosphatidylcholine. The activity of phospholipase A1 was found in a broad range of pH but no optimal pH was determined. The pH optimum of lysophospholipase was 8.0. Both enzymes were labile to heat. Phospholipase C activity, however, could not be detected because no radioactive di- and monoacylglycerol was found in the experiment with 1-acyl-2-[1-14C]-oleoyl-sn-glycero-3-phosphorylcholine as the substrate. It was inferred that phosphatidylethanolamine, which was the major component of phospholipids in leptospirae, was hydrolyzed serially by phospholipase A (A1 and/or A2?) and lysophospholipase to glycerophosphorylethanolamine via 2-acyl-type-lyso-derivative as one metabolic pathway of the substrate.
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PMID:Phospholipases of Leptospira. I. Presence of phospholipase A1 and lysophospholipase in Leptospira biflexa. 649 72

Lysophospholipase from human eosinophils is a protein previously considered based upon antigenic, enzymatic, and electrophoretic similarities to be the single component of Charcot-Leyden crystals, which are formed in vivo in association with eosinophilic diseases. The identity of eosinophil lysophospholipase and solubilized Charcot-Leyden crystal protein is now established by biochemical criteria, and a basis for the ease of aggregation and crystallization of the protein is identified in its prominent hydrophobicity. Chromatographically purified enzyme and Charcot-Leyden crystal protein formed in vitro functioned as lysophospholipases with identical Michaelis constants (Km approximately equal to 22 microM) for the substrate lysopalmitoylphosphatidylcholine and had blocked amino-terminal residues and almost identical amino acid compositions. The propensity of lysophospholipase to aggregate was not due to extensive intermolecular disulfide bonding because it contained a single cysteine residue as assessed by amino acid analyses and incorporated 0.986 mol of p-chloromercuribenzoic acid/mol of native enzyme or 0.958 mol of iodoacetic acid/mol of reduced and denatured enzyme. By equilibrium dialysis, lysophospholipase bound 3.820 g of detergent/g of protein in 1% sodium dodecyl sulfate and 0.506 g of detergent/g of protein in 10 mM sodium deoxycholate. In addition, monomeric protein demonstrated enhanced binding of detergent as evidenced by its aberrantly rapid electrophoretic mobility in 1%, but not 0.1%, sodium dodecyl sulfate. The hydrophobic nature of this protein, which accounts for 10% of the protein of the eosinophil, may contribute to its unique propensity for crystallization in vivo.
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PMID:Biochemical characterization of human eosinophil Charcot-Leyden crystal protein (lysophospholipase). 651 87

Lysophospholipase (EC 3.1.1.5) and phospholipase A2 (EC 3.1.1.4) were determined in ileal mucosa from patients with Crohn's disease (CD) and non-inflammatory bowel diseases ( NIBD ). In addition, the activities of alkaline phosphatase, sucrase, maltase, and lactase were determined. The lysophospholipase activity, like that of alkaline phosphatase, sucrase and maltase, was decreased in affected areas of CD, whereas the phospholipase A2 activity was rather increased. Lysophospholipase and phospholipase A2 activities in apparently unaffected mucosa from CD patients were in between those in healthy mucosa from NIBD patients and those in affected mucosa from CD patients. These findings point to the possibility that the mucosal activity of lysophospholipase, like that of other brush border enzymes, is decreased in CD. This may render the mucosa less capable to handle lysolecithin, a potentially harmful agent formed in the intestine and known to induce inflammation in a number of experimental systems.
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PMID:Decreased lysophospholipase and increased phospholipase A2 activity in ileal mucosa from patients with Crohn's disease. 672 69

Lysophospholipase-transacylase (lysolecithin acylhydrolase, EC 3.1.1.5) from rat lung catalyzes the transfer of acyl groups from lysophosphatidylcholine to either water or another molecule of lysophosphatidylcholine. Studies on the substrate specificity of the purified enzyme showed that a phosphate group in the substrate is essential for enzymatic activity; monoacylglycerol is not hydrolyzed, nor does it serve as an acceptor of acyl groups. The influence of the acyl chain in lysophosphatidylcholine was investigated by using mixtures of differently labelled lysophosphatidylcholine species, or by studying the transfer of [1-14C]Palmitate from [1-14C]palmitoylpropane (1,3)diol-phosphocholine to various 1-acyl-sn-glycero-3-phosphocholines. Lysophosphatidylcholines with acyl chains comprised of ten or more C-atoms were found to serve as acyl acceptors. This finding was used to determine the action of the enzyme on 1-[1-14C]auroyl- and 1[1-14C]myristoyl-sn-glycero-3-phosphocholine both below and above the critical micelle concentration of the substrate. Monomeric substrate was effectively hydrolyzed, but the transacylase activity of the enzyme was only expressed when substrate micelles were present. Likewise, no transacylase activity was found when lysophosphatidylcholine was embedded in liposomal membranes prepared from lung total lipids. These findings, which persist with crude enzyme preparations (100 000 x g supernatant), are discussed in relation to the putative function of the lysophospholipase-transacylase in the synthesis of disaturated phosphatidylcholine in lung.
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PMID:Substrate specificity of lysophospholipase-transacylase from rat lung and its action on various physical forms of lysophosphatidylcholine. 701 12

Metabolism of lysophosphatidylcholine (LPC), recently implicated in arrhythmogenesis, was characterized in rabbit ventricular homogenates. Activities of four enzymatic pathways were distinguishable after subcellular fractionation and DEAE-Sephacel chromatography including microsomal lysophospholipase, microsomal acyl coenzyme A/LPC acyltransferase, cytosolic lysophospholipase, and cytosolic lysophospholipase-transacylase. Microsomal lysophospholipase activity was attenuated 81% by acidosis comparable to that in ischemic myocardium (pH 6.5) and was inhibited by substrate. LPC acyltransferase was identified in the microsomal fraction based on CoA-dependent phosphatidyl choline synthesis, the positional specificity of acylation of LPC, and identical reaction velocities with both of its labeled co-substrates. LPC acyltransferase had a Vmax of 5.1 nmol/mg/min, a broad pH optimum centered at pH 7, and an apparent Km for LPC and palmitoyl-CoA of 14 microM and 7 microM. Cytosolic lysophospholipase was separated from lysophospholipase-transacylase by DEAE-Sephacel chromatography and distinguished from microsomal lysophospholipase by its broad pH activity curve, Michaelis-Menten kinetics (Vmax = 9.5 nmol/mg/min, Km = 7.5 microM), and lack of substrate inhibition. Lysophospholipase-transacylase was identified in the cytosolic fraction by CoA-independent phosphatidyl choline synthesis and purified 4885-fold from homogenate by ammonium sulfate precipitation, DEAE-Sephacel, hydroxylapatite, gel filtration, and polylysine chromatography. The partially purified enzyme had a transacylase/lysophospholipase activity ratio of 0.6, and transacylation of LPC was prominent at submicellar concentrations of substrate.
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PMID:Lysophosphatidylcholine metabolism in the rabbit heart. Characterization of metabolic pathways and partial purification of myocardial lysophospholipase-transacylase. 708 96

Phospholipase B (lysolecithin acyl-hydrolase, EC 3.1.1.5) from the mycelia of Penicillium notatum (Institute for Fermentation, Osaka, Japan; No.4640) was adsorbed from a crude solution to palmitoyl cellulose. Adsorption was efficient at pH 4 at low ionic strength (10 mM buffer), and at pH 4-9 at higher ionic strength (1-2M NaCl in 10 mM buffer). The adsorbed enzyme was eluted from the cellulose with a suitable detergent, such as Adekatol SO-120, Triton X-100, or deoxycholate. As an application of this procedure, the enzyme was purified from an extract of the mycelia by column chromatography on a palmitoylated textile (palmitoylated gauze) with an overall recovery of 59% and a 38-fold increase in specific activity. By subsequent column chromatographies on Amberlite XAD-2, Sephadex G-100 and G-150, and DEAE-Sephadex A-50, the enzyme was purified about 4,000-fold to a nearly homogeneous state from a mycelium extract with an overall recovery of 37%.
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PMID:Purification of phospholipase B from Penicillium notatum by hydrophobic chromatography on palmitoyl cellulose. 737 59


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