title: Purification and some properties of protamine kinase from rabbit brain.
abstract: A protein kinase of high specificity towards protamine and ATP was isolated from rabbit brain and purified about 200-fold. The enzyme does not catalyse phosphorylation of acidic proteins, e.g. casein and phosvitin, nor is it susceptible to cyclic AMP or protein inhibitors of the cAMP-dependent kinase. The enzyme shows the highest activity in the presence of 10 mM-Mg2+ and 2 mM-dithiothreitol at pH 8. The only phosphorylated amino acid found in protamine phosphorylated by the enzyme was phosphoserine.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000201:enzymology*; D002845:Chromatography; D004229:Dithiothreitol / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000494:pharmacology; D010768:Phosphoserine / Q000378:metabolism; D006656:Protamine Kinase; D011479:Protamines / Q000378:metabolism; D011494:Protein Kinases / Q000302:isolation & purification / Q000378:metabolism*; D011817:Rabbits; D013379:Substrate Specificity
chemical_list: D011479:Protamines; D010768:Phosphoserine; D000255:Adenosine Triphosphate; D011494:Protein Kinases; D006656:Protamine Kinase; D008274:Magnesium; D004229:Dithiothreitol