[Phospholipids of E. coli and activity of alkaline phosphatase]

The effects of liposomes prepared from the E. coli lipids on the activity of soluble alkaline phosphatase and on the complementation reaction between its subunits were studied. It was shown that the liposomes nonspecifically catalyze the dimerization of the enzyme subunits without changing the dimer activity. The effects of phospholipases A2 and C on the activity of membrane-bound alkaline phosphatase were studied. An interrelationship was found between the level of hydrolysis of membrane phosphatidyl glycerol (PG) by these enzymes and the changes in the activity of membrane-bound alkaline phosphatase. It was also shown that PG is less accessible to the effects of phospholipases in the cells with derepressed biosynthesis of alkaline phosphatase. It is assumed that the membrane PG interacts with the membrane-bound alkaline phosphatase during its translocation into the periplasm.