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)

A lysophospholipase from Escherichia coli cells was purified about 1,500-fold to near homogeneity by extraction with Tris-HCl buffer, streptomycin treatment, (NH4)2SO4 fractionation, column chromatographies on Sephadex G-200, DEAE-cellulose and hydroxylapatite-cellulose, and polyacrylamide gel electrophoresis. The final preparation had a molecular weight of 39,500 plus or minus 500. The enzyme hydrolyzes 1-acylglycerylphosphorylethanolamine, 2-acylglycerylphosphorylethanoiamine, and 1-acylglycerylphosphorylglycerol, but does not attack diacylphospholipids with long chain fatty acids, such as phosphatidylethanolamine and phosphatidylglycerol. The enzyme does not show any esterase activity against p-nitrophenyl acetate or palmitate. Although it does not hydrolyze triacylglycerol or diacylglycerol, it hydrolyzes 1-acylglycerol at almost the same rate as 1-acyl-sn-glycerol-3-phosphorylethanolamine. Results indicated that the acyl-hydrolyzing activities toward monoacyl-glycerylphosphorylethanolamine and monoacylglycerol belong to the same enzyme. In general, acidic and nonionic detergents inhibited the reaction. This lysophospholipase preparation hydrolyzes the monomolecular and micellar forms of lysophospholipids as well as of monoacylglycerol. The monomolecular and micellar forms of Triton X-100 both inhibited the hydrolyses of lysophospholipids and monoacylglycerol.
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PMID:Lysophospholipase of Escherichia coli. 23 79

Phospholipase B inhibitor was found in the autolyzate of yeast cells, Torulaspora delbrueckii. The inhibitor was purified to homogeneity by ethanol precipitation, gel filtration with Sephadex G-10, ion-exchange chromatography with DEAE-Sephacel, and gel filtration with Asahipak GS-320. On thin-layer chromatography the purified inhibitor was detected with the Hanes-Isherwood reagent, which is used to detect phosphorus. The activity of the inhibitor was not affected by heat treatment at 100 degrees C for 1 h. Heating at 100 degrees C for 1 h in 1 M HCl and 1 M NaOH lowered activity to 76 and 80% of the original values, respectively, but heating at 110 degrees C for 24 h in 6 M HCl completely abolished activity. The inhibitor was highly soluble in water, but practically insoluble in alcohol, acetone, ether, and chloroform. The degree of inhibition of enzyme activity was not proportional to the concentration of inhibitor. The inhibitor inhibited both membrane-bound and water-soluble phospholipase B activity from T. delbrueckii at the same level; however, the inhibitor did not inhibit the activity of phospholipase A2 from snake venom (Naja naja).
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PMID:Isolation and fundamental characteristics of a phospholipase B inhibitor from autolyzed Torulaspora delbrueckii. 176 Jan 34

Membrane-bound phospholipase B was purified to a homogeneous state from Torulaspora delbrueckii cell homogenate. Cell homogenate was extracted with Triton X-100, and the enzyme was precipitated with acetone. The acetone powder was washed repeatedly with Tris-HCl buffer (pH 8.0) until no phospholipae B activity was detected in the soluble fraction. The enzyme was extracted with Triton X-100 from the final residue and purified about 1,390-fold by sequential chromatofocusing, Sepharose 6B, and DEAE-Sephadex A-50 column chromatography. The final preparation showed a single broad protein band on SDS-polyacrylamide gel electrophoresis when stained with silver stain reagent and PAS-reagent. The molecular weight of phospholipase B was about 390,000 and 140,000-190,000 as estimated by gel filtration on Sepharose 6B and SDS-polyacrylamide gel electrophoresis, respectively, suggesting that phospholipase B is an oligomeric protein. The isoelectric point was at pH 4.5. Phospholipase B has two pH optima, one acidic (pH 2.5-3.0) and the other alkaline (pH 7.2-8.0). At acidic pH the phospholipase B activity was greatly increased in the presence of divalent metal ions, although metal ions are not a factor for enzyme activity. On the other hand, at alkaline pH the enzyme required Ca2+ or Mn2+ for activity. The pH- and thermal-stabilities at both pHs were similar. The phospholipase B hydrolyzed all diacylphospholipids tested at acidic pH, but hydrolyzed only phosphatidylcholine at alkaline pH. The hydrolysis rates of lysophospholipids were much higher (about 10-fold) than those of diacylphospholipids at both pHs.
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PMID:Purification and some properties of membrane-bound phospholipase B from Torulaspora delbrueckii. 318 65

Two types of phospholipase B of Penicillium notatum, the native type and the modified type that is thought to be generated by the introduction of some nicks into the native type of enzyme by the endogenous protease(s), were distinguished on a slab sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis under a nonreducing condition. The native form migrated with a rate corresponding to 95K Da, whereas the modified form migrated more slowly, corresponding to 106K Da, presumably because of its more extended conformation. That the "106K" protein was indeed a nicked product of the "95K" protein was confirmed by amino acid analysis, peptide mapping, N- and C-terminal sequence analyses, and immunoblotting. The peptide fragments (70K and 37K + 32K) comprising the modified protein were isolated by gel filtration in the presence of SDS and 2-mercaptoethanol (the 32K peptide was suggested to be a partial proteolytic product of the 37K peptide). When the "95K" protein was subjected to the same treatment under denaturing condition, it retained a low, but significant, enzymatic activity; in contrast, the separated peptide fragments did not show any significant activity. By a coincubation of these fragments, however, a restoration of enzymatic activity was observed through a reformation of the active complex, corresponding to the original modified protein. The enzymatic activity of this complex was further increased by a treatment with guanidine X HCl, followed by dialysis. The association of peptide fragments appears to occur through the formation of interpeptidal disulfide bonds.
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PMID:Molecular relationship between two types of phospholipase B from Penicillium notatum and reconstitution of active enzyme from its peptide fragments. 354 77