Purification and properties of a distinct protamine kinase from the cytosol of bovine kidney cortex.
A protamine kinase has been purified to apparent homogeneity from extracts of the cytosol of bovine kidney cortex. This protamine kinase exhibited an apparent Mr = 43,000 as estimated by gel permeation chromatography on Sephacryl S-200 and an apparent Mr = 45,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified protamine kinase exhibited about 5% activity with casein, 8% with histone H2B, and less than 0.1% with histone H1, histone H4, glycogen synthase a from rabbit skeletal muscle, ovalbumin, bovine serum albumin, and phosvitin. The activity of the highly purified protamine kinase was unaffected by cyclic AMP (up to 0.1 mM), cyclic GMP (up to 0.1 mM), the heat-stable protein inhibitor of cyclic AMP-dependent protein kinase (up to 100 micrograms/ml), heparin (up to 100 micrograms/ml), EGTA (up to 1 mM), Ca2+ (up to 1 mM), calmodulin (up to 0.5 microM) in the absence or presence of Ca2+ (0.05 mM), and phosphatidylserine (up to 40 micrograms/ml) and/or diolein (up to 1 microgram/ml) in the absence or presence of Ca2+ (up to 0.5 mM). Experiments in which extracts of kidney cytosol were incubated with [gamma-32P]ATP and MgCl2 revealed that the phosphorylation of numerous polypeptides was markedly increased in the presence of the purified protamine kinase. The results indicate that this protamine kinase of kidney cytosol is a novel protein kinase.
Damuni
Z
Z
Department of Biology, University of South Carolina, Columbia 29208.
Amick
G D
GD
Sneed
T R
TR
D000818:Animals; D002417:Cattle; D003600:Cytosol / Q000201:enzymology; D007672:Kidney Cortex / Q000201:enzymology*; D008274:Magnesium / Q000494:pharmacology; D008928:Mitochondria / Q000201:enzymology; D008970:Molecular Weight; D006656:Protamine Kinase; D011494:Protein Kinases / Q000302:isolation & purification* / Q000502:physiology; D013379:Substrate Specificity
D011494:Protein Kinases; D006656:Protamine Kinase; D008274:Magnesium