A comparison of molecular properties of hepatic triglyceride lipase and lipoprotein lipase from human post-heparin plasma.

作者：Jan Augustin, Hudson H. Freeze, P. Tejada, W. Virgil Brown · 发表于：Journal of Biological Chemistry · 年份：1978 · DOI：10.1016/s0021-9258(17)40782-4 · 被引用次数：80 · 研究领域：Lipid metabolism and disorders、Lipid metabolism and biosynthesis、Diabetes, Cardiovascular Risks, and Lipoproteins

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.