title: Selective utilization of endogenous unsaturated phosphatidylcholines and diacylglycerols by cholinephosphotransferase of mouse lung microsomes.
abstract: In the presence of CMP, cholinephosphotransferase of mouse lung microsomes catalyzes the conversion of endogenous phosphatidylcholines into 1,2-diacyl-sn-glycerols and CDPcholine. 2. In this conversion cholinephosphotransferase shows a distinct preference for those molecular species of phosphatidylcholine which contain an unsaturated fatty acid. The enzyme hardly utilizes endogenous depalmitoylglycerophosphocholine as a substrate. 3. Membrane-bound 1,2-diacyl-sn-glycerols were also prepared by treatment of mouse lung microsomes with a pure phospholipase C from Bacillus cereus. These 1,2-diacyl-sn-glycerols were subsequently utilized as substrate by cholinephosphotransferase in the formation of phosphatidylcholine. In the latter reaction, cholinephosphotransferase exhibited a pronounced preference for unsaturated 1,2-diacyl-sn-glycerols and hardly utilized the endogenous 1,2-depalmitoyl-sn-glycerol. 4. The low affinity of cholinephosphotransferase for either dipalmitoylglycerophosphocholine or 1,2-dip
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002794:Choline / Q000378:metabolism; D002798:Diacylglycerol Cholinephosphotransferase / Q000378:metabolism*; D004075:Diglycerides / Q000378:metabolism*; D004533:Egtazic Acid / Q000494:pharmacology; D005989:Glycerides / Q000378:metabolism*; D007700:Kinetics; D008168:Lung / Q000201:enzymology*; D051379:Mice; D008861:Microsomes / Q000201:enzymology*; D010169:Palmitic Acids / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism*; D010770:Phosphotransferases / Q000378:metabolism*
chemical_list: D004075:Diglycerides; D005989:Glycerides; D010169:Palmitic Acids; D010713:Phosphatidylcholines; D004533:Egtazic Acid; D010770:Phosphotransferases; D002798:Diacylglycerol Cholinephosphotransferase; D002794:Choline; D002118:Calcium