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PubMed · 4715328

Diglyceride kinase in human platelets.

F L Call·M Rubert
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Abstract

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.

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Adenosine TriphosphateBlood PlateletsBuffersChromatography, Ion ExchangeChromatography, PaperChromatography, Thin LayerDeoxycholic AcidErythrocytesGlyceridesHumansHydrogen-Ion ConcentrationKineticsLymphocytesMagnesiumOsmolar ConcentrationPhospholipidsPhosphorus IsotopesPhosphotransferasesSulfhydryl ReagentsSurface-Active AgentsTime FactorsJournal Article

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F L Call, M Rubert. 1973. Diglyceride kinase in human platelets.. https://pubmed.ncbi.nlm.nih.gov/4715328/

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