title: Phospholipase activities in subcellular fractions of human platelets.
abstract: A homogenate of human platelets was fractionated by zonal ultracentrifugation into membranes, various granules and mitochondria. The membrane fraction was composed of two populations. The first, which represented 75% of the proteins, was rich in plasma membranes; the second, which represented the remaining 25%, was rich in microsomal membranes. Lysophospholipase was essentially localised in the cytosol. Phospholipase A1 which was only weakly bound to membranes, was mostly found in the soluble fraction (75%); the remainder was located in the plasma membranes and the mitochondria. Two-thirds of the phospholipase A2 was found in the particulate fractions.
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000201:enzymology*; D002462:Cell Membrane / Q000201:enzymology; D002501:Centrifugation, Zonal; D003600:Cytosol / Q000201:enzymology; D006801:Humans; D008244:Lysophosphatidylcholines; D008297:Male; D010740:Phospholipases / Q000378:metabolism*; D013347:Subcellular Fractions / Q000201:enzymology
chemical_list: D008244:Lysophosphatidylcholines; D010740:Phospholipases