Resident mouse peritoneal macrophages have three phospholipase activities: a phospholipase A2 active at pH 4.5, a Ca2+-dependent phospholipase A2 active at pH 8.5 and a phosphatidylinositol-specific phospholipase C activity. When macrophages are exposed to zymosan in culture, the cellular activity of pH-4.5 phospholipase A2 is diminished in a manner dependent on zymosan concentration and time o...

A new, rapid, and sensitive assay for phospholipase A, utilizing commercially available [14C]phosphatidylethanolamine with 14C label in both palmitic acid moieties, was used to study phospholipase A release from perfused liver, hepatocytes, and intestinal cells from rats. Heparin triggered a prompt release of phospholipase A from perfused liver. Phospholipase A and triglyceride lipase were rele...

The role of protein kinase C in the mechanism of phospholipase D activation by platelet-derived growth factor and 12-O-tetradecanoylphorbol-13-acetate was studied in Swiss/3T3 fibroblasts that overexpress protein kinase C-alpha. Production of [3H]phosphatidylpropanol (specific product of the phospholipase D-catalyzed transphosphatidylation reaction) was determined in cells which were prelabeled...

The phospholipase A(2) family includes secretory phospholipase A(2), cytosolic phospholipase A(2), plasmalogen-selective phospholipase A(2), and calcium-independent phospholipase A(2). It is generally thought that the release of arachidonic acid by cytosolic phospholipase A(2) is the rate-limiting step in the generation of eicosanoids and platelet activating factor. These lipid mediators play c...

phospholipase a1 is known as an effective catalyst for hydrolysis of various phospholipids in enzymatic vegetable oil degumming. immobilization is one of the most efficient strategies to improve its activity, recovery and functional properties. in this study, chitosan-co-polyethylene oxide (90:10) nanofibrous mat was successfully fabricated and modified with atmospheric plasma at different time...

background and objectives: phosphlipases are a group of enzymes that breakdown phosphatidylcholine (phospholipids) molecules producing second products. these produced products have a divers role in the cell like signal transduction and digestion in humans. in this research the effect of phosphatidylcholine on the expression of plc genes of a. fumigatus was studied. the plc genes of this fungus ...

The role of phospholipid in rat liver microsomal glucose 6phosphatase has been investigated with the use of phospholipase A and phospholipase C to alter the microsomal phospholipids. The phospholipase C-treated preparation lost a maximum of 80 to 90% of the original activity, and 70% of the microsomal phospholipid was hydrolyzed. Addition of phospholipid completely restored the original activit...

Pig phospholipase A2, pig iso-phospholipase A2 and bovine pancreatic phospholipase A2 were reacted in solution with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, in the presence of N-hydroxysulfosuccinimide, at pH 7. The influence of micellar protectants was analyzed. In the presence of n-hexadecylphosphocholine, the losses of activity in micellar diheptanoyl-lecithin were 80, 35, and 10% in b...

Calcium dependent phospholipase A2 activity in the mixed micelles of 1-palmitoyl-2-oleoyl-phosphatidylglycerol and cholate was measured in sera of 39 patients with Crohn's disease, 40 patients with ulcerative colitis, and 40 healthy controls. The phospholipase A2 activity was significantly raised in those sera of the patients with active Crohn's disease and those with moderate and severe ulcera...