Hasegawa-Sasaki H, Ohno K
Biochim Biophys Acta. 1980 Feb 22;617(2):205-17.
Acyl-CoA:1-acyl-sn-glycero-3-phosphocholine acyltransferase (EC 2.3.1.23) was extracted from rat liver microsomes with an aqueous dispersion of 1-acyl-sn-glycero-3-phosphocholine, a substrate of the enzyme, and purified up to 30-fold. The procedure includes removal of unrelevant proteins and lipids by washings of microsomes with a buffer of high ionic strength and with buffers containing detergents, extraction of the enzyme with an aqueous dispersion of 1-acyl-sn-glycero-3-phosphocholine, and chromatography by gel filtration. The acyltransferase was eluted from a Ultrogel AcA 34 column at a position with a Kav of 0.122; an elution position of a protein with a molecular weight of 225 000. The partially purified enzyme was active over a wide range of pH with an optimum at around pH 8. Depending on the acyl donors, different rates of the reaction were obtained by the preparation. The order was: arachidonoyl-CoA greater than linoleoyl-CoA = oleoyl-CoA greater than palmitoyl-CoA. The enzyme preparation acylated 1-acyl-sn-glycero-3-phosphocholine, 1-acyl-sn-glycero-3-phospho-ethanolamine and 1-acyl-sn-glycero-3-phosphoinositol but not acylated 2-acyl-sn-glycero-3-phosphocholine, 1-acyl-sn-glycerol 3-phosphate or diacylglycerol. Some sulfhydryl-binding reagents inactivated the enzyme.
酰基辅酶A：1-酰基-sn-甘油-3-磷酸胆碱酰基转移酶（EC 2.3.1.23）用该酶的底物1-酰基-sn-甘油-3-磷酸胆碱的水分散液从大鼠肝脏微粒体中提取，并纯化了30倍。该步骤包括用高离子强度缓冲液和含去污剂的缓冲液洗涤微粒体以去除无关蛋白质和脂质，用1-酰基-sn-甘油-3-磷酸胆碱的水分散液提取酶，以及通过凝胶过滤进行色谱分析。酰基转移酶从Ultrogel AcA 34柱上以Kav为0.122的位置洗脱；这是分子量为225000的蛋白质的洗脱位置。部分纯化的酶在很宽的pH范围内都有活性，最适pH约为8。根据酰基供体的不同，该制剂获得了不同的反应速率。顺序为：花生四烯酰辅酶A＞亚油酰辅酶A = 油酰辅酶A＞棕榈酰辅酶A。该酶制剂可使1-酰基-sn-甘油-3-磷酸胆碱、1-酰基-sn-甘油-3-磷酸乙醇胺和1-酰基-sn-甘油-3-磷酸肌醇酰化，但不能使2-酰基-sn-甘油-3-磷酸胆碱、1-酰基-sn-甘油3-磷酸或二酰基甘油酰化。一些巯基结合试剂可使该酶失活。
