Wong M, Brown R E, Barenholz Y, Thompson T E
Biochemistry. 1984 Dec 18;23(26):6498-505. doi: 10.1021/bi00321a035.
Glycolipid transfer protein from bovine brain has been purified partially by ammonium sulfate precipitation, CM-52 ion-exchange, and Sephadex G-75 column chromatography. Both pyrene-labeled and tritium-labeled glucocerebrosides have been used to study the kinetics of protein-mediated transfer between donor and acceptor vesicles. Protein accelerates glucocerebroside transfer but does not accelerate phospholipid transfer. In colyophilized small sonicated vesicles (10% glucocerebroside, 90% 1-palmitoyl-2-oleoyl-phosphatidylcholine) about two-thirds of the glycolipid is transferred in 2 h and the remaining one-third does not transfer (up to 5 h). For donor and acceptor vesicles made of dipalmitoylphosphatidylcholine or 1-palmitoyl-2-oleoyl-phosphatidylcholine, glucocerebroside (10% in donors) is transferred rapidly only when both the donor and acceptor matrix phospholipids are in the liquid-crystalline state. If either donor or acceptor vesicles are in the gel state, transfer protein mediated transfer is much reduced. The amount of transfer protein bound specifically to glucocerebroside-containing vesicles is nearly equal above and below the matrix phospholipid phase transition temperature. Bound protein transfers glucocerebroside upon addition of acceptor vesicles.
牛脑糖脂转移蛋白已通过硫酸铵沉淀、CM - 52离子交换和葡聚糖凝胶G - 75柱色谱法进行了部分纯化。已使用芘标记和氚标记的葡萄糖脑苷脂来研究蛋白质介导的供体囊泡与受体囊泡之间转移的动力学。该蛋白可加速葡萄糖脑苷脂的转移，但不能加速磷脂的转移。在冻干的小超声处理囊泡（10%葡萄糖脑苷脂，90% 1 - 棕榈酰 - 2 - 油酰 - 磷脂酰胆碱）中，约三分之二的糖脂在2小时内转移，其余三分之一不转移（长达5小时）。对于由二棕榈酰磷脂酰胆碱或1 - 棕榈酰 - 2 - 油酰 - 磷脂酰胆碱制成的供体和受体囊泡，只有当供体和受体基质磷脂均处于液晶态时，葡萄糖脑苷脂（供体中为10%）才会快速转移。如果供体或受体囊泡处于凝胶态，转移蛋白介导的转移会大大减少。在基质磷脂相变温度上下，特异性结合含葡萄糖脑苷脂囊泡的转移蛋白量几乎相等。加入受体囊泡后，结合的蛋白会转移葡萄糖脑苷脂。
