Bansal V S, Kanfer J N
Biochim Biophys Acta. 1985 Aug 22;836(1):73-9. doi: 10.1016/0005-2760(85)90222-x.
The phospholipid-N-methyltransferase activity of rat brain microsomes had an optimum pH of 11.0 in the absence or presence of phosphatidylethanolamine (PE) but pH 10.0 in the presence of phosphatidylmonomethylethanolamine (PMME) or phosphatidyldimethylethanolamine (PDME). An apparent Km for S-adenosyl methonine from 0.10 to 0.12 mM was observed with exogenous methylated phospholipids PMME or PDME. Methylated neutral lipid was the major lipid produced in the absence of the exogenous acceptors. Two exogenous phospholipids, PMME and PDME, significantly stimulated microsomal phospholipid-N-methyltransferase activity and the predicted methylated phospholipids were the major products. PE additions did not cause any stimulation of methylated lipid formation. Preincubation of particles at temperatures from 40 to 100 degrees C resulted in a loss in the microsomal phospholipid-N-methyltransferase activity that was stimulated by PMME and PDME.
在不存在或存在磷脂酰乙醇胺（PE）的情况下，大鼠脑微粒体的磷脂-N-甲基转移酶活性的最适pH值为11.0，但在存在磷脂单甲基乙醇胺（PMME）或磷脂二甲基乙醇胺（PDME）的情况下，最适pH值为10.0。在外源甲基化磷脂PMME或PDME存在下，观察到S-腺苷甲硫氨酸的表观Km为0.10至0.12 mM。在不存在外源受体的情况下，甲基化中性脂质是主要产生的脂质。两种外源磷脂PMME和PDME显著刺激微粒体磷脂-N-甲基转移酶活性，预测的甲基化磷脂是主要产物。添加PE不会对甲基化脂质的形成产生任何刺激。将微粒在40至100摄氏度的温度下预孵育会导致微粒体磷脂-N-甲基转移酶活性丧失，而该活性受到PMME和PDME的刺激。
