A Fluorescent-Based Assay for Measurement of Phospholipase A2 Activity: A Facile Assay for Cell Sonicates

Phospholipases A 2 (PLA 2 ) catalyze the hydrolysis of the ester bond at the sn-2 position of phospholipids to generate the lysophospholipid and free fatty acid ( 1 ). Several classes of PLA 2 s have been identified ( 2 ). They include the low molecular weight-secreted enzymes, which demonstrate a requirement for millimolar concentrations of Ca 2+ for full activity and are generally involved in the inflammatory response. The high molecular-weight, cytosolic PLA 2 s are activated by submicromolar calcium, have specificity for unsaturated fatty acids and arachidonic acid in particular ( 3 , 4 ). The arachidonic acid released can have many direct functions or can serve as a precursor in the formation of the numerous prostaglandin and leukotriene products ( 5 ). Thus, it is becoming increasingly clear that this latter class of enzymes are the principle regulators of arachidonic-acid release and therefore play an important role in signal transduction ( 6 ). These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.