A new myotoxic phospholipase A2 was isolated from the venom of the arboreal snake Bothriechis schlegelii (formerly Bothrops schlegelii) from Costa Rica, by ion-exchange chromatography on CM-Sephadex. B. schlegelii myotoxin I is a basic protein (pI > 9.3) with a subunit molecular weight of 15 kDa, which migrates as a dimer in sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonred...

To determine the mechanism of calcium-dependent membrane binding of cytosolic phospholipase A2 (cPLA2), we measured the interactions of cPLA2 with phospholipid monolayers and polymerizable mixed liposomes containing various phospholipids. In the presence of calcium, cPLA2 showed much higher penetrating power than secretory human pancreatic PLA2 toward anionic and electrically neutral phospholip...

Ca2+-mobilizing agonists, including hormones, neurotransmitters and growth factors, cause profound changes in cellular lipid metabolism. These changes are initiated by receptormediated activation of various phospholipases including phospholipase A2, phospholipase C and phospholipase D. Phospholipase A2 hydrolyses several phospholipids including phosphatidylinositol, phosphatidylcholine (PtdCho)...

Highly purified acidic (pI 4.9) and basic (pI 8.7) phospholipases A2 from snake (Agkistrodon halys blomhoffii) venom hydrolyzed approximately 20% and 60%, respectively, of the phosphatidylcholine (PC) of intact human erythrocytes prior to hemolysis. Sequential use of the acidic enzyme followed by the basic phospholipase A2 or vice versa manifested a characteristic PC hydrolysis pattern. For exa...

BACKGROUND Phospholipase A(2) (PLA(2)) is involved in regulating biosynthesis of arachidonic acid and its metabolites. There are three major structurally different forms of PLA(2): group I, also called pancreatic PLA(2) (PLA(2)-I); group II, referred to as secretory non-pancreatic or synovial or platelet PLA(2) (PLA(2)-II); group IV, referred to as cytosolic PLA(2) (PLA(2)-IV). AIMS To examin...

In kidney epithelial cells, an angiotensin II (Ang II) type 2 receptor subtype (AT2) is linked to a membrane-associated phospholipase A2 (PLA2) and the mitogen-activated protein kinase (MAPK) superfamily. However, the intervening steps in this linkage have not been determined. The aim of this study was to determine whether arachidonic acid mediates Ang II's effect on p21ras and if so, to ascert...