Cholinephosphotransferase activity in human platelets.

G Goracci; P Gresele; G Arienti; P Porrovecchio; G G Nenci; G Porcellati

doi:10.1007/bf02534545

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Cholinephosphotransferase activity in human platelets.

G Goracci·P Gresele·G Arienti·P Porrovecchio·G G Nenci·G Porcellati

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Abstract

Disrupted human platelets possess a cholinephosphotransferase activity (EC 2.7.8.2) whose properties have been studied in this work. The labeling of choline glycerophospholipid (CGP) from radioactive cytidine-5'-diphosphate choline (CDP-choline) in vitro shows a maximum at pH 8.0 (using Hepes [4-(2-hydroxyethyl)-piperazine-1-ethane-2-sulfonic acid] as a buffer) and is stimulated by Mn2+, Mg2+ and diacylglycerol. The enzymic activity is inhibited by Ca2+. The dependence of human platelet cholinephosphotransferase upon CDP-choline concentration does not follow the Michaelis-Menten equation. CMP strongly inhibits the reaction. The functional implications of this newly discovered platelet activity are briefly considered.

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Blood Platelets Blood Proteins Cations, Divalent Chemical Phenomena Chemistry Diacylglycerol Cholinephosphotransferase Diglycerides Enzyme Activation Humans Hydrogen-Ion Concentration Phosphotransferases Journal Article Research Support, Non-U.S. Gov't

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G Goracci, P Gresele, G Arienti, P Porrovecchio, G G Nenci, G Porcellati. 1983. Cholinephosphotransferase activity in human platelets.. https://doi.org/10.1007/bf02534545

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