The role of the phosphate group for the structure of phosphopeptide products of adenosine 3',5'-cyclic monophosphate-dependent protein kinase.
By c.d. studies it is shown that liver-pyruvate-kinase-related peptide substrates of cyclic AMP-dependent protein kinase have a high tendency towards non-random structures in non-aqueous media. When phosphorylated, the conformation tendencies decrease. This structural change is explained in terms of the formation of strong intrapeptide phosphate-guanidinium salt links. It is proposed that similar events occur at the catalytic site of protein kinase and that such an interaction could facilitate the removal of the phosphorylated products.
D001665:Binding Sites; D002942:Circular Dichroism; D000242:Cyclic AMP / Q000378:metabolism; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D015636:Magnesium Chloride; D010455:Peptides / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism; D010748:Phosphopeptides / Q000378:metabolism*; D010766:Phosphorylation; D011487:Protein Conformation; D011494:Protein Kinases / Q000378:metabolism*
D010455:Peptides; D010710:Phosphates; D010748:Phosphopeptides; D015636:Magnesium Chloride; D000242:Cyclic AMP; D011494:Protein Kinases; D008274:Magnesium