Wang C S, Hartsuck J A, Weiser D
Biochim Biophys Acta. 1985 Nov 14;837(2):111-8. doi: 10.1016/0005-2760(85)90233-4.
The incubation of human plasma very-low-density lipoprotein with human milk lipoprotein lipase results in an almost complete hydrolysis of triacylglycerols. The degradation of these substrates can be described by a consecutive reaction as follows: (Formula: see text), where k1, k2 and k3 are the apparent first-order rate constants of degradation. Using least-squares non-linear curve fitting, k1 and k2 are determined to be directly proportional to enzyme concentration. k1/k2 ratio of 1:12 is similar for both VLDL and trioleoylglycerol substrates of lipoprotein lipase. However, when trioleoylglycerol and rac-1,2-dioleoylglycerol are used as substrates, a direct measurement indicates a k1/k2 ratio of 1:1.5. This result suggests that the intermediary diacylglycerol produced by the lipoprotein reaction is incompletely re-equilibrated with the bulk of the substrate in the assay mixture. The k3 value is not proportional to lipoprotein lipase concentration, and in the enzyme concentration range studied, the value decreases when the enzyme concentration increases.
人血浆极低密度脂蛋白与人乳脂蛋白脂肪酶一起温育会导致三酰甘油几乎完全水解。这些底物的降解可用如下连续反应来描述：（公式：见原文），其中k1、k2和k3是降解的表观一级速率常数。使用最小二乘非线性曲线拟合，确定k1和k2与酶浓度成正比。对于脂蛋白脂肪酶的极低密度脂蛋白和三油酰甘油底物，k1/k2比值均为1:12。然而，当使用三油酰甘油和外消旋1,2 - 二油酰甘油作为底物时，直接测量表明k1/k2比值为1:1.5。该结果表明，脂蛋白反应产生的中间二酰甘油在测定混合物中与大量底物未完全重新达到平衡。k3值与脂蛋白脂肪酶浓度不成正比，在所研究的酶浓度范围内，该值随酶浓度增加而降低。
