[Properties of phospholipase D from rat liver mitochondria].

The properties of membrane-bound mitochondrial phospholipase D were investigated. The enzyme was shown to catalyze the hydrolysis of endogenous mitochondrial phospholipids, particularly phosphatidylethanolamine. The phospholipase activity was maximal at pH 5.0 and 7.0 was stimulated by Ca2+ and sodium oleate and was inhibited by SDS. The conditions for solubilization of the mitochondrial enzyme and its adsorption on a biospecific adsorbent were elaborated. The adsorption resulted in a 17-fold purification of the enzyme with a 33% yield. The adsorbed enzyme, similar to the membrane-bound one, was activated by Ca2+ and sodium oleate but, in contrast to the latter, was able to catalyze the hydrolysis of an exogenous substrate.