Aguilar J S, de Cózar M, Criado M, Monreal J
J Neurochem. 1983 Feb;40(2):585-8. doi: 10.1111/j.1471-4159.1983.tb11323.x.
It has been very difficult to prepare the apoprotein moiety of brain white matter proteolipid so that it is completely devoid of complex lipids, without suffering aggregation and protein denaturation. The reason is that complex lipids are tightly bound to the proteolipid apoprotein. Using a new ultrafiltration method, we obtained, in a gradual way and in a relatively short time, more than 99% delipidation in water-saturated n-butanol, with and without 0.1 M acetic acid, and recovered up to 86% of the protein with no detectable reducing sugars remaining. The delipidated protein remained in solution and in a relatively nondenatured state for several days. In 2% sodium dodecyl sulfate (SDS)-aqueous media, 90% of the lipids were removed and the yield of recovered protein in solution was near 90%; nearly 6% of the reducing sugars remained in the apoprotein. A higher delipidation was obtained by washing with 0.1 M NaOH. The content of reducing sugars was greater but the protein was less stable. When 10% SDS was employed to dissociate lipid-protein interaction, an almost complete delipidation was obtained and reducing sugars disappeared.
制备脑白质蛋白脂质的载脂蛋白部分非常困难，要使其完全不含复合脂质，又不发生聚集和蛋白质变性。原因是复合脂质与蛋白脂质的载脂蛋白紧密结合。使用一种新的超滤方法，我们在相对较短的时间内逐步实现了在水饱和正丁醇中，无论有无0.1 M乙酸，脱脂率超过99%，并且回收了高达86%的蛋白质，没有检测到残留的还原糖。脱脂后的蛋白质在溶液中保持相对未变性的状态达数天之久。在2%十二烷基硫酸钠（SDS）水介质中，90%的脂质被去除，溶液中回收蛋白质的产率接近90%；载脂蛋白中仍残留近6%的还原糖。用0.1 M NaOH洗涤可获得更高的脱脂率。还原糖含量更高，但蛋白质稳定性较差。当使用10% SDS解离脂质-蛋白质相互作用时，几乎实现了完全脱脂，还原糖消失。
