Partially dephosphorylated phosphopeptide AcSer(P)‐Ser(P)‐Ser(P) is an excellent substrate for casein kinase‐2

FEBS Letters

Johns, Reginald B.¹  Pinna, Lorenzo A.²  Meggio, Flavio²  Perich, John W.¹ 

[1] Department of Organic Chemistry, University of Melbourne, Parkville, 3052 Victoria, Australia;Dipartimento di Chimica Biologica, Università di Padova, Padova, Italy

关键词: Casein kinase-2;    Phosphopeptide;    Phosphoserine;    Specificity determinant;    [Ser-P] ncluster;   

DOI  :  10.1016/0014-5793(88)80206-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The synthetic phosphopeptide AcSer(P)-Ser(P)-Ser(P), reproducing a recurrent feature of casein and other phosphoproteins, once partially dephosphorylated by acid phosphatase, serves as an efficient substrate for casein kinase-2. Previous dephosphorylation beyond 30% hinders subsequent phosphorylation and the entirely dephosphorylated peptide is not a substrate at all. The kinetic constants of the partially dephosphorylated phosphopeptide are much more favourable than those of the synthetic peptides SEEEAA, SSEE and SEE, the latter one being totally inert. Optimal phosphorylation occurs at pH values that ensure complete ionization of the phosphoseryl side chains. These data provide incontrovertible demonstration that phosphoserine can replace carboxylic amino acids as specificity determinant for CK-2, being more effective than glutamic acid itself.

【 授权许可】

Unknown