Call F L, Rubert M
J Lipid Res. 1973 Jul;14(4):466-74.
Human platelets contain diglyceride kinase, an enzyme that catalyzes the phosphorylation of diacylglycerol by adenosine 5'-triphosphate to yield phosphatidic acid. The majority of the platelet enzyme is particulate-bound, and membrane fractions of platelet homogenates have a higher specific activity than granule fractions. Both deoxycholate and magnesium are necessary for optimal enzyme activity. The K(m) of the enzyme for adenosine 5'-triphosphate is 1.3 mm, and the apparent K(m) for diacylglycerol is 0.4 mm. The pH optimum is 6.6-6.8 in imidazole-HCl or maleate-NaOH buffer. The enzyme activity of platelets from normal subjects was similar to the activity from patients with renal and hepatic failure.
人血小板含有甘油二酯激酶，该酶催化二酰基甘油由腺苷5'-三磷酸磷酸化生成磷脂酸。血小板酶的大部分与颗粒结合，血小板匀浆的膜部分比颗粒部分具有更高的比活性。脱氧胆酸盐和镁对于最佳酶活性都是必需的。该酶对腺苷5'-三磷酸的K(m)为1.3 mM，对二酰基甘油的表观K(m)为0.4 mM。在咪唑 - HCl或马来酸 - NaOH缓冲液中，最适pH为6.6 - 6.8。正常受试者血小板的酶活性与肾衰竭和肝功能衰竭患者的活性相似。
