Calmodulin-Dependent Protein Kinase II (290-309) acetate is a potent CaMK antagonist with an IC50 of 52 nM for inhibition of Ca2+/calmodulin-dependent protein kinase II[1].
Peptide 290 to 309 is found to be a potent calmodulin antagonist with an IC50 of 52 nM for inhibition of Ca2+/calmodulin-dependent protein kinase. Neither truncation from the amino terminus (peptide 296-309) nor extension in the carboxyl-terminal direction (peptide 294-319) markedly affects calmodulin binding, whereas shortening the peptide from the carboxyl terminus (peptide 290-302) or from both ends (peptide 295-304) results in the elimination of this activity[1].
[1]. Payne ME, et al. Calcium/calmodulin-dependent protein kinase II. Characterization of distinct calmodulin binding and inhibitory domains. J Biol Chem. 1988 May 25;263(15):7190-5.