title: Evidence that phosphatidylcholine and phosphatidylethanolamine are synthesized by a single enzyme present in the endoplasmic reticulum of castor-bean endosperm.
abstract: Increasing concentrations of CDP-choline progressively inhibit the measured incorporation of CDP-[2-14C]ethanolamine into phosphatidylethanolamine catalysed by the ethanolaminephosphotransferase present in endoplasmic-reticulum membranes isolated from castor-bean endosperm cells. This inhibition parallels that observed during CDP-[Me-14C]choline incorporation and suggests that a single enzyme utilizes both these substrates.
mesh_terms: D002367:Ricinus communis / Q000201:enzymology*; D002798:Diacylglycerol Cholinephosphotransferase / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000201:enzymology*; D010713:Phosphatidylcholines / Q000096:biosynthesis*; D010714:Phosphatidylethanolamines / Q000096:biosynthesis*; D010770:Phosphotransferases / Q000378:metabolism; D010947:Plants, Toxic; D012278:Ricinus / Q000201:enzymology*
chemical_list: D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010770:Phosphotransferases; D002798:Diacylglycerol Cholinephosphotransferase