[Separation and properties of molecular forms of phospholipase D from plants]

Abstract

The optimal conditions for isolation and purification of phospholipase D (EC 3.1.4.4) from Middle-Asian radish tubers, cotton plant seeds and cabbage leaves using biospecific chromatography on polyamide absorbent with covalently linked phosphatidylethanolamine, were elaborated. The synthetic absorbent can be used for separation of molecular enzyme forms differing in their affinity for immobilized phosphatidylethanolamine (forms I, II, and III). Experimental evidence for the interconvertibility and interrelationship of different forms of plant phospholipase D is given. It is demonstrated that forms I and III separated by biospecific chromatography are represented by enzyme conformers distinguishable by their thermal stabilities (phospholipases D1 and Ds, respectively), while form II is a high molecular weight phospholipase D.