• YAKHAK HOEJI
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• v.27 no.4
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• pp.249-256
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• 1983

When the reaction rate constant k of phospholipase D on liposome was measured by the ANS fluorometry, k of phospholipase D on DMPC liposome which was made of L-$\alpha$-PI, cholesterol and L-$\alpha$-PS decreased than that of phospholipase D on DMPC liposome with cholesterol or with PI and cholesterol. Optimal $Ca^{2+}$ concentration, the most important factor on effect of phospholipase D, also decreased to 1mM, as compared with 10mM and 60mM respectively when cholesterol and PI were added, and cholesterol only was added. The change of cholesterol Mol% had a great influence on k value of phospholipase D. But in case of addition of L-$\alpha$-PS to cholesterol, the influence was relatively diminished.

• Journal of the Korean Chemical Society
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• v.52 no.5
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• pp.488-494
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• 2008

• The Journal of the Korean Society for Microbiology
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• v.22 no.4
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• pp.403-411
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• 1987

This study investigated whether a correlation exists between proteinase activity, phospholipase activity and adherence of Candida albicans to buccal epithelial cells by using of various strains isolated from oral cavity. The proteinase activity of 30 strains was tested by culture on agar media that contained bovine serum albumin as a nitrogen source. Using the serum-protein-agar method to test proterolysis of serum albumin in 20 strains of Candida albicans. Twenty-six strains of Candida albicans were phospholipase producers and the degree of phopholipase activity of experimental strains were $0.51{\sim}0.89$ measured by Pz-value. Twenty-eight strains of Candida albicans were adhersive to buccal epithelial cells and 15 strains were foung significantly active adherence. Fifteen strains of Candida albicans were correlated with proteinase activity and adherence to epithelial cells and concomitantly 20 strains of Candida albicans were also correlated with phospholipase activity and adherence. In conclusion our investigation provides evidence of a correlation between quantitative proteinase, phospholipase and adherence. An association of these parameters may be an important contributory factor for pathogenicity.

• YAKHAK HOEJI
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• v.39 no.5
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• pp.554-559
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• 1995

MT 2511-5 was purified as a inhibitor of phospholipase C(PLC) from culture broth of a Streptmyces sp. NO. 2511-5. It was identified as scopafungin, 36-membered marcrolide by physico-chemical and spectroscopic data. Its $IC_{50}$ was 30.mu.M against phospholipase C and it also showed inhibitory activity against some fungi.

• The Korean Journal of Pharmacology
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• v.27 no.2
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• pp.191-196
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• 1991

The present study was performed to determine whether estradiol, via cAMP mediation, induces prostaglandin synthesis by modulating phospholipase $A_2$ activity which hydrolyzes phospholipids into arachidonic acids, a precursor for prostaglandin synthesis, during the implantation process in rats. Uterine phospholipase $A_2$ activity was elevated on day 5 of pregnancy when implantation normally occurs in rats. Moreover, phospholipase $A_2$ activity was higher in the implant sites than in the non-implant sites of uterus on day 6. In delayed implantation model, phospholipase $A_2$ activity was increased at 12 hrs after estradiol administration and at 8 hrs after dbcAMP administration. In addition, higher activity of phospholipase $A_2$ was induced by the treatment of estradiol plus theophylline, compared with estradiol-only treated group. The simultaneous treatment of indomethacin with estradiol or dbcAMP did not alter phospholipase $A_2$ activity compared with estradiol or dbcAMP-only treated group although significant suppression was observed in uterine PGE and $PGF_{2{\alpha}}$ concentrations. These results suggest that estradiol or cAMP stimulates uterine phospholipase $A_2$ activity, thereby increasing prostaglandin synthesis during the implantation process in rats.

• BMB Reports
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• v.30 no.2
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• pp.101-105
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• 1997

Extracellular phospholipase $A_2$ activity has been detected in urine of patients with acute pyelonephritis (APN). This enzyme required micromolar $Ca^{2+}$ ion for its maximum activity and showed a broad range of pH (4.5~10) optimum. Urine enzyme hydrolyzed phosphatidylethanolamine (PE) and phosphatidylserine (PS) more effectively than phosphatidylcholine (PC). $PLA_2$ activity in the urine of patients with APN was about 5-fold higher than that of healthy individuals. When urine was subjected to heparinSepharose column chromatography, phospholipase $A_2$ activity was detected in both heparin-non-binding and binding fractions. Both phospholipase $A_2$ activities were sensitive less than a micromolar calcium concentration and did not react with anti-human 14-kDa group II phospholipase $A_2$ monoclonal antibody, HP-l. These findings suggest that two kinds of novel extracellular phospholipase $A_2$. which may not belong to the 14-kDa group II phospholipase $A_2$ family, exist in the urine of patients with APN.

• YAKHAK HOEJI
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• v.49 no.5
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• pp.405-409
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• 2005

To investigate anti-inflammatory activity of Noni extracts, we measured the phospholipase $A_2$ activity using both in vitro and in vivo system. Water soluble fraction of Noni extracts did not affect melittin-induced arachidonic acid release, whereas lipid soluble fraction inhibited it in a dose dependent manner in Raw 264.7 cells. The purified phos­pholipase $A_2$ activity was dose-dependently inhibited by lipid soluble fraction of Noni extracts but not by its water soluble fraction. Lipid peroxidation, myeloperoxidase and phospholipase $A_2$ activity in incised skin of mice were significantly increased as compared with those in non-incised skin, and these increase was attenuated by the treatment with Noni pow­der. Our data suggest that Noni extracts has anti-inflammatory activity, and this is, in part, caused by inhibitory activity of phospholipase $A_2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.908-913
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• 1997

The purpose of this study was to investigate phospholipase $A_{2}$ activity and lipid peroxidation I streptozotocin induced diabetic rats. Sprague-Dawley male rats weighting-Dawley male rats weighting 300$\pm$10gm were randomly assigned to normal and STZ-induced diabetic group. Diabetes was induced by intravenous injection of 55mg/kg of STZ in sodium citrate buffer(pH 4.3). Animals were sacrificed at the 6th day of diabetic states. Body weight gains were lower in DM group. Phosphatidylcholine hydrolysis in liver was not significantly different between two groups, whereas phosphatidylethanolamine hydrolysis in liver was increased by 69% in DM group comparing with that of normal group. Liver microsomal phospholipase $A_{2}$ activity and level of TBARS was increased by 91%, 109% in DM group compared with that of normal group, respectively. The present results indicate that phospholipase $A_{2}$ activity is specific to PE hydrolysis, leading to lipid peroxidation process in STZ induced diabetic rats.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.354-361
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• 2005

Vibrio fluvialis, an enteropathogenic bacterium, produces a phospholipase which is thought to be an important factor in the pathogenesis of disease. In this study, the phospholipase gene (vfp) was identified from V fluvialis (KCTC 2473) and its sequence was determined. The entire open reading frame was composed of 1,689 nuc1eotides and 563 amino acids. The phospholipase gene (vfp) was overexpressed in Escherichia coli as a his-tag fused protein. This recombinant protein (rVFP58) was solubilized with 6 M urea and purified by Ni-NTA affinity chromatography. The action mode of rVFP58 was determined by TLC and GC-MS, and it showed phospholipase B activity, which had both phospholipase A and lysophospholipase activities. The rVFP58 showed a maximum activity at pH around 9- 10 and temperature of about 40OC, and it was stable under alkaline condition over pH 9. The cytotoxicity of rVFP58 was evaluated, using a fish cell line, CHSE-2l4, and was found to cause significant cell death after 14 h of exposure to 250 $\mu$g of the protein.

• Journal of Microbiology
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• v.38 no.3
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• pp.150-155
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• 2000

A bioluminescent assay method for detecting the activity of phospholipase C(PLC; phosphatidyl choline cholinephosphohydrolase, EC 3.1.4.3) was developed using bioluminescent marine bacteria. Phospholipase C from Bacillus cereus and sn-1,2- dimyristoyl glycerol was further hydrolyzed with lipase from Candida ecylidracea. The hydrolyzed myristic acid was quantified using a dark mutant of Vibrio harveyi (designated as M-17). The in vivo light intensity of which was stimulated specifically up to one thousand fold in the presence of myristic acid. The rates of the hdrolysis of the DMPC substrate by the phospholipase measured by the luminescence method were linear with time and the were estalished to detect as little as 0.1 mUnit of phospholipase C and 5 nM of myristic acid production.