从大鼠肝脏溶酶体中分离出的磷脂酶C的特性

Properties of phospholipase C isolated from rat liver lysosomes.

作者信息

Matsuzawa Y, Hostetler K Y

出版信息

J Biol Chem. 1980 Jan 25;255(2):646-52.

Abstract

Phospholipase C (EC 3.1.4.3) has been identified in a soluble, delipidated protein fraction isolated from rat liver lysosomes. Lysosomal phospholipase C is active against all phospholipids tested, including phosphatidylcholine, phosphatidylinositol, phosphatidylglycerol, phosphatidylethanolamine, and phosphatidylserine. It has an acid pH optimum, does not require divalent cations, and is not inhibited by EDTA. With [1-14C]dioleoylphosphatidylcholine as the substrate, 14C-labeled monoglyceride and diglyceride are the reaction products. Monoglyceride is formed rapidly from diglyceride by a lysosomal acid lipase, although some monoglyceride may be formed directly by phospholipase C hydrolysis of lysophosphatidylcholine. The other product, phosphocholine, has been identified by its behavior during Dowex 1-formate anion exchange chromatography. This appears to be the first demonstration in mammalian systems ofa phospholipase C which is active against all phosphoglycerides.

摘要

磷脂酶C（EC 3.1.4.3）已在从大鼠肝脏溶酶体中分离出的可溶性脱脂蛋白组分中被鉴定出来。溶酶体磷脂酶C对所有测试的磷脂都有活性，包括磷脂酰胆碱、磷脂酰肌醇、磷脂酰甘油、磷脂酰乙醇胺和磷脂酰丝氨酸。它的最适pH为酸性，不需要二价阳离子，且不受EDTA抑制。以[1-14C]二油酰磷脂酰胆碱为底物时，14C标记的甘油单酯和甘油二酯是反应产物。甘油单酯可由甘油二酯通过溶酶体酸性脂肪酶迅速形成，不过一些甘油单酯可能也由磷脂酶C对溶血磷脂酰胆碱的水解直接形成。另一种产物磷酸胆碱已通过其在Dowex 1-甲酸盐阴离子交换色谱中的行为得到鉴定。这似乎是首次在哺乳动物系统中证明一种对所有磷酸甘油酯都有活性的磷脂酶C。