Inactivation of the catalytic subunit of bovine cAMP-dependent protein kinase by a peptide-based affinity inactivator.
A peptide affinity inactivator, Ac-Leu-Arg-Arg-Ala-(BrAc)Orn-Leu-Gly, was used as a tool to probe for active site residues in the catalytic subunit of bovine cAMP-dependent protein kinase. The peptide inactivated the catalytic subunit in an active site-directed and monophasic manner with a first-order rate constant of 0.03 min-1 and a dissociation constant of 675 microM. Studies with radioactive peptide indicated that approximately one equivalent of peptide was incorporated into each protein molecule. Protein sequencing identified the modified residue as Cys-199. A possible location for Cys-199 within the active site is suggested.
Mobashery
S
S
Department of Chemistry, Wayne State University, Detroit, Michigan 48202.
Doughty
M
M
Kaiser
E T
ET
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D007700:Kinetics; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000378:metabolism* / Q000494:pharmacology; D047428:Protein Kinase Inhibitors
D009842:Oligopeptides; D047428:Protein Kinase Inhibitors