Augustin J, Freeze H, Tejada P, Brown W V
J Biol Chem. 1978 May 10;253(9):2912-20.
Hepatic triglyceride lipase was isolated from human post-heparin plasma by the method of Ehnholm et al. using modifications which increased the specific activity 12-fold to approximately 3,000 mumol of free fatty acid/h/mg of protein. Lipoprotein lipase with similar specific activity was prepared from the same plasma samples using heparin and concanavalin A affinity chromatography. The molecular weight of hepatic triglyceride lipase (69,000) was slightly greater than that of lipoprotein lipase (67,000) as determined by polyacrylamide electrophoresis in sodium dodecyl sulfate-containing buffers. These proteins had identical amino acid compositions, terminal amino acid residues, and tryptic peptide maps. However, the differences previously described regarding optima of pH and ionic strength and the requirement for apolipoprotein CII (only for lipoprotein lipase) were maintained in the highly purified state. It was found that both proteins contain approximately 8% carbohydrate. Antisera prepared in goats selectively precipitated each activity. Other antisera prepared in chickens reacted with both enzymes, suggesting a common antigenic determinant.
采用埃恩霍尔姆等人的方法从人肝素后血浆中分离出肝甘油三酯脂肪酶，并进行了改进，使比活性提高了12倍，达到约3000微摩尔游离脂肪酸/小时/毫克蛋白质。使用肝素和伴刀豆球蛋白A亲和色谱法从相同血浆样本中制备了具有相似比活性的脂蛋白脂肪酶。通过在含十二烷基硫酸钠的缓冲液中进行聚丙烯酰胺电泳测定，肝甘油三酯脂肪酶的分子量（69,000）略大于脂蛋白脂肪酶（67,000）。这些蛋白质具有相同的氨基酸组成、末端氨基酸残基和胰蛋白酶肽图。然而，先前描述的关于pH和离子强度最佳值以及对载脂蛋白CII的需求（仅脂蛋白脂肪酶需要）的差异在高度纯化状态下得以保留。发现这两种蛋白质都含有约8%的碳水化合物。用山羊制备的抗血清选择性地沉淀了每种活性。用鸡制备的其他抗血清与两种酶都发生反应，表明存在共同的抗原决定簇。
