Diphosphoinositide metabolism in bovine adrenal medulla.
(1) A phosphatidylinositol kinase (EC 2.7.1.67) of a chromaffin vesicle membrane preparation isolated from bovine adrenal medulla was characterized. Its activity towards endogenous and exogenous phosphatidylinositol was very similar to the kinase activity of the microsomal fraction prepared from the same tissue. (2) Phosphomonoesterase (EC 3.1.3.36) and diesterase activity hydrolysing membrane bound phosphatidylinositol 4-phosphate was located mainly in the microsomal fraction. No hydrolytic activity was present in the vesicle membrane. (3) Phosphorylation of chromaffin vesicle membrane phosphatidylinositol did not increase calcium-binding by the membranes.
D000313:Adrenal Medulla / Q000201:enzymology*; D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D002458:Cell Fractionation; D003594:Cytoplasmic Granules / Q000378:metabolism; D007700:Kinetics; D008566:Membranes / Q000201:enzymology; D008861:Microsomes / Q000201:enzymology; D010716:Phosphatidylinositols / Q000378:metabolism*; D010770:Phosphotransferases / Q000378:metabolism*; D013347:Subcellular Fractions / Q000201:enzymology; D013501:Surface-Active Agents / Q000494:pharmacology
D010716:Phosphatidylinositols; D013501:Surface-Active Agents; D010770:Phosphotransferases; D002118:Calcium