title: The effect of Fe2+ on the activity of human plasma protein kinase.
abstract: A Fe2+ stimulatory protein kinase in human plasma is demonstrated. This enzyme was partial purified from the 100,000 X g supernatant of human plasma by using (NH4)2SO4 fractionation. The activity of this protein kinase existed in 30-50% fraction. The effect of various compounds on the activity of this partial purified protein kinase was studied. The Fe2+ stimulates 5 to 10-fold of the protein kinase activity. The maximum concentration of Fe2+ to stimulate the activity of this plasma protein kinase was 2 mM. Double reciprocal plot for the stimulation showed that Fe2+ increased the Vm but not the Km for ATP. Other divalent compounds such as MgCl2, Mg(Oac)2, MnCl2 and BaCl2 were less effective.
mesh_terms: D001798:Blood Proteins / Q000302:isolation & purification / Q000378:metabolism; D002413:Cations, Divalent; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007501:Iron / Q000494:pharmacology*; D007700:Kinetics; D010766:Phosphorylation; D011494:Protein Kinases / Q000097:blood* / Q000302:isolation & purification
chemical_list: D001798:Blood Proteins; D002413:Cations, Divalent; D007501:Iron; D011494:Protein Kinases