Merck, P0270-200UN, Calmodulin from bovine heart

Application
This is the protein activator required for the Ca²⁺ dependent activation of phosphodiesterase, 3′:5′-cyclic nucleotide, P0520.
Biochem/physiol Actions
Ca²⁺ binding protein that is required for activation of cyclic nucleotide-dependent phosphodiesterase. It is also a cofactor/activator of nitric oxide synthase, calcineurin, and many kinases including ATPase, myosin light chain kinase, and CAM kinase I, II, and III. It mediates ryanodine receptor activation by cyclic ADP ribose and is involved in intracellular Ca²⁺ homeostasis.
Physical form
Lyophilized powder containing buffer salts as imidazole and magnesium sulfate
Preparation Note
Purified by a modification of the procedure of Teo, T.S., et al., J. Biol. Chem., 248, 588 (1973).
Other Notes
One unit will stimulate 0.008 activated unit of phosphodiesterase, 3′:5′-cyclic nucleotide, P0520, in a 3 mL reaction volume at pH 7.5 and 30 °C, to 50% of the maximum activity of the enzyme when saturated with activator, in the presence of 0.01 mM Ca²⁺.