PKA Inhibitor (5-24) (trifluoroacetate salt)

PKI PKA Inhibitor (5-24) is a synthetic peptide inhibitor of PKA (cAMP-dependent protein kinase) (K_i = 2.3 nM) derived from the active site of the skeletal muscle inhibitor protein.¹ It mimics the protein substrate by binding to the catalytic site through the arginine-cluster basic subsite.¹ The prominent enzyme-substrate interaction site occurs where PKA catalytic subunit residues Tyr²³⁵ and Phe²³⁹ form a sandwich-like structure with residue Phe¹⁰ of PKI (5-24).²

1.Cheng, H.C., Kemp, B.E., Pearson, R.B., et al.A potent synthetic peptide inhibitor of the cAMP-dependent protein kinaseThe Journal of Biological Chemisty261(3)989-992(1986) 2.Bossemeyer, D., Engh, R.A., Kinzel, V., et al.Phosphotransferase and substrate binding mechanism of the cAMP-dependent protein kinase catalytic subunit from porcine heart as deduced from the 2.0 Å structure of the complex with Mn2+ adenylyl imidodiphosphate and inhibitor peptide PKI(5-24)EMBO Journal12(3)849-859(1993)