Synthetic hexapeptide substrates and inhibitors of 3':5'-cyclic AMP-dependent protein kinase.
- 1 April 1976
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 73 (4) , 1038-1042
- https://doi.org/10.1073/pnas.73.4.1038
Abstract
The substrate specificity of the catalytic subunit of rabbit skeletal muscle 3': 5'-cyclic AMP-dependent protein kinase (EC 2.7.1.37; ATP: protein phosphotransferase) has been studied using the synthetic peptide Arg-Gly-Tyr-Ser-Leu-Gly corresponding to the sequence around serine 24, a phosphorylation site in reduced, carboxymethylated, maleylated (RCMM) chicken egg white lysozyme. This peptide served as a substrate for the enzyme and exhibited a 6-fold higher Vmax and a 100-fold higher Km than RCMM-lysozyme. Replacement of the arginine with glycine, histidine, or lysine resulted in a dramatic reduction in the Vmax. These results support the concept that arginine is an important residue in determining the substrate specificity of the protein kinase, predominantly influencing the Vmax of the phosphorylation reaction. Two synthetic peptides in which serine was replaced by an alanine acted as competitive inhibitors of phosphorylation of the synthetic peptide substrate and RCMM-lysozyme.Keywords
This publication has 11 references indexed in Scilit:
- Synthetic substrate for cyclic AMP-dependent protein kinaseNature, 1975
- Non-dependence on native structure of pig liver pyruvate kinase when used as a substrate for cyclic 3′,5′-AMP-stimulated protein kinaseBiochemical and Biophysical Research Communications, 1975
- Substrate specificity of the cyclic AMP-dependent protein kinase.Proceedings of the National Academy of Sciences, 1975
- Effect of denaturation on the susceptibility of proteins to enzymic phosphorylationJournal of Biological Chemistry, 1975
- Investigation of the sites phosphorylated in lysine‐rich histones by protein kinase from pig brainFEBS Letters, 1975
- The Hormonal Control of Activity of Skeletal Muscle Phosphorylase KinaseEuropean Journal of Biochemistry, 1975
- Peptides from myelin basic protein as substrates for adenosine 3′, 5′-cyclic monophosphate-dependent protein kinasesBiochemical and Biophysical Research Communications, 1974
- Amino acid sequence of a (32P)phosphopeptide from pig liver pyruvate kinase phosphorylated by cyclic 3′,5′-AMP-stimulated protein kinase and γ-(32P)ATPBiochemical and Biophysical Research Communications, 1974
- Krebs EG: Purification and characterization of a protein inhibitor of adenosine 3',5'-monophosphate-dependent protein kinases.1971
- The Synthesis of Ribonuclease AJournal of Biological Chemistry, 1971