Kanoh H, Ohno K
Biochim Biophys Acta. 1975 Feb 20;380(2):199-207.
Rat liver microsomes containing 1,2-diacylglycerols formed from the endogenous phosphatidycholines by the action of 1,2-diacylglycerol: CDPcholine cholinephosphotransferase (E.C. 2.7.8.2.) were used as a source of enzymes and substrates. A marked selectivity of 1,2-diacylglycerol: CDPethanolamine ethanolaminephosphotransferase (E.C. 2.7.8.1.) was revealed for utilizing endogenous hexaenoic diaglycerol, while cholinephosphotransferase utilized without marked selectivity the endogenous 1,2-diacylglycerol species differing in the degree of unsaturation. By using microsomes prepared after injecting the animals with 1-acyl lysophosphatidylcholines labeled with radioactive myristic, palmitic, and stearic acids, the selectivity of the transferases towards the saturated fatty acids in the 1-position of the endogenous substrates was studied. In incubation of the labeled microsomes with CMP, cholinephosphotransferase appeared to utilize 1-myristyl phosphatidylcholine most rapidly and, in decreasing order, the 1-palmityl and 1-stearyl species. Ethanolaminephosphotransferase utilized the endogenous 1-stearyl diacylglycerol in preference to 1-palmityl type.
含有通过1,2 - 二酰基甘油：CDP胆碱胆碱磷酸转移酶（E.C. 2.7.8.2.）作用由内源性磷脂酰胆碱形成的1,2 - 二酰基甘油的大鼠肝微粒体被用作酶和底物的来源。揭示了1,2 - 二酰基甘油：CDP乙醇胺乙醇胺磷酸转移酶（E.C. 2.7.8.1.）在利用内源性六烯二酰甘油方面具有显著的选择性，而胆碱磷酸转移酶在利用不饱和度不同的内源性1,2 - 二酰基甘油种类时没有明显的选择性。通过使用给动物注射用放射性肉豆蔻酸、棕榈酸和硬脂酸标记的1 - 酰基溶血磷脂酰胆碱后制备的微粒体，研究了转移酶对内源性底物1位饱和脂肪酸的选择性。在用CMP孵育标记的微粒体时，胆碱磷酸转移酶似乎最快速地利用1 - 肉豆蔻酰磷脂酰胆碱，其次是1 - 棕榈酰和1 - 硬脂酰种类，且利用速率依次降低。乙醇胺磷酸转移酶优先利用内源性1 - 硬脂酰二酰基甘油而非1 - 棕榈酰类型。
