Synthesis of ethanolamine phosphoglycerides by human platelets.
Platelet homogenates contain an ethanolaminephosphotransferase (EC 2.7.8.1) that catalyzes the synthesis of ethanolamine phosphoglycerides from cytidine-5'-diphosphate ethanolamine and 1-radyl-2-acyl-sn-glycerols. The enzyme is particulate-bound and requires Mn2+ and bile salts for optimal activity. The apparent Km of the enzyme for cytidine-5'-diphosphate ethanolamine is 1.6 X 10(-5) M when the concentration of 1,2-diacyl-sn-glycerols is 8.8 X 10(-4) M. The pH optimum is 8.5 in Tris-HCl or glycine-NaOH buffer. The activity of the enzyme in platelets from normal subjects is 0.24-0.34 nmole/min/mg of protein.
D001792:Blood Platelets / Q000201:enzymology*; D004912:Erythrocytes / Q000201:enzymology; D004983:Ethanolamines; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009702:Nucleoside Diphosphate Sugars; D010714:Phosphatidylethanolamines / Q000096:biosynthesis / Q000097:blood*; D010770:Phosphotransferases / Q000097:blood*; D013347:Subcellular Fractions / Q000201:enzymology
D004983:Ethanolamines; D009702:Nucleoside Diphosphate Sugars; D010714:Phosphatidylethanolamines; D010770:Phosphotransferases