RESUMO
A fraction with phospholipase A2 activity [EC 3,1,1,4] has been purified from Ascaris worms by a combination of gel filtration on Sephadex G-100 [fine] and ion exchange chromatography on DEAE-Sephacel. The enzyme showed a single band by SDS-polyacrylamide gel electrophoresis and had a molecular weight of about 19,000. The final preparation was purified 46 fold. It has 18% carbohydrate content. Optimum temperature for enzyme activity was 50°C and the optimum pH was 6.0. It has a Km value about 79 mg/L. It could be activated by calcium, manganese and cobalt and it was inhibited by EDTA and iodoacetate. Studying kinetics of phospholipase may be of value in developing a chemotherapeutic agent that inhibits parasite lipid metabolism with consequent inhibition of its vital activities resulting in parasite control