A novel binding assay for phospholipase A2.

S H Peers; R D Taylor; R J Flower

doi:10.1016/0006-2952(87)90672-1

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PubMed · 3318845

A novel binding assay for phospholipase A2.

S H Peers·R D Taylor·R J Flower

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Abstract

We have devised a rapid and simple assay for estimating the binding of pancreatic phospholipase A2 to a bilayer lipid membrane. The binding was observed to be extremely rapid at 37 degrees and was absolutely dependent upon Ca2+. Amongst several drugs known to inhibit the catalytic activity of phospholipase only mepacrine at high concentrations (500 microM) and chlorpromazine (100 microM) were active. Treatment of the enzyme with p-bromophenacylbromide did not inhibit binding. Several alcohols potentiated binding whereas detergents tended to inhibit. Amongst several purified proteins tested, only the steroid-induced anti-phospholipase protein lipocortin prevented binding. The use of this assay in screening for antiphospholipase agents is discussed.

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Binding Sites Binding, Competitive Calcium Escherichia coli Kinetics Ligands Membranes Phospholipases Phospholipases A Phospholipases A2 Journal Article Research Support, Non-U.S. Gov't

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S H Peers, R D Taylor, R J Flower. 1987-12-15. A novel binding assay for phospholipase A2.. https://doi.org/10.1016/0006-2952(87)90672-1

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