Existence of cytosolic phospholipase D. Identification and comparison with membrane-bound enzyme.

摘要: In a wide variety of cells, phosphatidylcholine hydrolysis in response to diverse agents is catalyzed by phospholipase D (PLD) activities that are believed be membrane-bound. Indeed, PLD has been detected membrane fractions several tissues and cells. We now demonstrate various bovine tissue including lung, brain, spleen, heart, kidney, thymus, liver as well rat lung great majority the detectable activity cytosolic. This cytosolic differs from less abundant membrane-bound isozyme chromatographic mobilities on anion exchange gel filtration columns, substrate specificity, concentration dependence, divalent cation detergent effects. Fractionation cytosol chromatography enhances up 20-fold, suggesting presence inhibitory factor(s). conclude mammalian exists multiple forms appropriate selection assay conditions critical for observing cytosol.