Comparison of cAMP-dependent protein kinase substrate specificity in reaction with proteins and synthetic peptides.
Mutants of L-type pyruvate kinase with modified peptide sequence around the Ser-12 phosphorylation site were prepared and kinetics of their phosphorylation by protein kinase A was studied. The profile of substrate specificity obtained for these proteins was compared with the kinetic data of phosphorylation of short peptide substrates. Alterations made in protein structure caused weaker effects than the corresponding alterations made in peptides, while the amino acid preferences and the overall specificity pattern remained similar in the both cases. Thus, similar consensus motif holds for both protein and peptide substrates, but is less critical for recognition of proteins if compared with short peptides.
Loog
Mart
M
Department of Medical Biochemistry and Microbiology, University of Uppsala, S-75 123 Uppsala, Sweden.
Oskolkov
Nikita
N
O'Farrell
Fergal
F
Ek
Pia
P
Järv
Jaak
J
D002384:Catalysis; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D010455:Peptides / Q000138:chemical synthesis / Q000378:metabolism*; D010766:Phosphorylation; D011770:Pyruvate Kinase / Q000378:metabolism; D013379:Substrate Specificity
D010455:Peptides; D011770:Pyruvate Kinase; D017868:Cyclic AMP-Dependent Protein Kinases