Inhibition of cyclic AMP-dependent protein kinase by analogues of a synthetic peptide substrate.

摘要: Analogues of the synthetic substrate Leu-Arg-Arg-Ala-Ser-Leu-Gly in which serine is replaced by other amino acids inhibited activity catalytic subunit cyclic AMP-dependent protein kinase from beef skeletal muscle (Peak I). All analogues were competitive with respect to peptide but apparent Ki values varied depending on particular acid that was substituted for serine. Inhibition also mixed histone as determined experiments utilizing one analogues. Acetylation terminal group lowered Km this 16 micrometer 3 micrometer, a similar modification inhibitory analogue Leu-Arg-Arg-Ala-Ala-Leu-Gly resulted no major change value. An amount sufficient inhibit 90% caused less than 10% inhibition several AMP-independent kinases indicating high degree specificity The show could be useful identifying phosphorylation reactions catalyzed distinguished reactions.