Purification and characterization of phospholipase A2 from bovine prostate

Phospholipase A2 (PLA2) was purified from bovine prostate by ammonium sulphate precipitation and fractionation by anion exchange chromatography, chromatofocusing and gel filtration. The purified enzyme was Ca(2+)-dependent and had a pH-optimum of 8.0. Ba2+, Fe2+, Hg2+, Mg2+, Pb2+, Sr2+ and Zn2+ as well as lysophosphatidylcholine, lysophosphatidylethanolamine and p-bromophenacyl bromide (p-BPB) inhibited the enzyme strongly. The enzyme had an estimated molecular weight of 12,000 +/- 1,000 daltons on SDS-PAGE. Isoelectric focusing showed one PLA2 activity-containing band at pl 5.3. The purified enzyme hydrolysed linoleic acid at the sn-2 position of phosphatidylcholine and phosphatidylethanolamine with high selectivity, compared to arachidonic acid.