Ordered phosphorylation of a duplicated minimal recognition motif for cAMP‐dependent protein kinase present in cardiac troponin I

FEBS Letters

Jaquet, K.¹  Heilmeyer, L.M.G.¹  Mittmann, K.¹ 

[1] Ruhr-Universität Bochum für Physiologische Chemie, Abteilung für Biochemie Supramolekularer Systemem, 4630 Bochum 1, Germany

关键词: Cardiac troponin 1;    Troponin I peptide: cAMP-dependent protein kinase;    Phosphoserine;    Ordered phosphorylation;    Tryptic cleavage;   

DOI  :  10.1016/0014-5793(92)80423-E

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Cardiac troponin I contains two adjacent serines in sequence after three arginine residues thus making up a minimally duplicated recognition motif for cAMP-dependent protein kinase. In a synthetic peptide, PVRRRSSANY, the two serine residues are phosphorylated sequentially with the intermediate formation of a monophosphorylated species according to the following reaction sequence: Peptide k ₁|→ Peptide-P k ₂|→ Peptide-P₂. The calculated rate constants are: k ₁ = 0.435 min⁻¹ and k ₂ = 0.034 min⁻¹. Sequence analyses of the monophosphopeptide and its tryptic fragments show that the predominant monophosphoform carries phosphate at the second serine.

【 授权许可】

Unknown