Possible Interaction: Caseins and Spermine

“Only at low Mg2+ concentration spermine enhanced by 68% the rate of casein phosphorylation.”

“Nuclear casein kinase II activity was present in … fractions as evidenced by the capacity of spermine to stimulate (ED50 = 0.19 mM) and heparin to … (ID50 = 0.09 μg/ml) the phosphorylation of casein ; further, the phosphotransferase activity could be purified by … casein-agarose and spermine-agarose affinity chromatography.”

“The Vmax of CK-1 for both casein and ATP is increased by spermine while the Km remains unchanged by the polyamine.”

“Abstract: An analysis of the effects of polyamines on protein phosphorylation … fractions of the pupal brain of Manduca sexta showed that spermine elicited an … in casein phosphorylation in a dose‐dependent manner (maximum three‐ to fourfold at 2.… mM), whereas spermidine was less effective and putrescine was without effect.”

“These studies were conducted by holding ionic strength constant at 0.10 M. At low Mg2+ (2.5 mM), activation by spermine resulted in a 33% decrease in the apparent Km for casein.”

“When casein was used as a substrate, spermine stimulated the enzyme activity 7.3-fold at 2 mM, and a 6.5-fold stimulation was observed with 6 mM spermidine.”

“Phosphorylation of casein was stimulated by polyamines, particularly spermine.”

“In the presence of excess Mg2+, phosphorylation of casein by the kinase was stimulated by spermine (1-5 mM) and was inhibited completely by 0.1 microgram/ml heparin.”

“The apparent Km for casein was reduced in the presence of spermine.”

“ Spermine decreased the apparent Km for casein and increased the maximum velocity of the reaction.”

“Phosphorylation of casein is stimulated by spermine.”